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  1. #401  
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    Quote Originally Posted by florian View Post
    This a fundamental mistake. The pacific unlike other oceans did notstart with a MOR. It started as an asymmetric ocean with successiveaddition of oceanic crust at the periphery of an initial core ocean(175 My old).This is shown in this figure:


    See the clear pattern? Theoldest ocean floor is at the center, and the age get younger goingoutward. In fact the EPR formed along the active margin of americasand continue to do so. The nascent ridge in the gulf of californiawill soon join the EPR to the south, and the Juan de Fuca to theNorth, by propagating thru the San Andreas Fault system.


    Eduction, a processdescribed by the russian geologist Yu Chudinov, explains very wellthe peripheral growth of the pacific:
    A process which is, seen nowhere else?! and not seen active happening?! It also predicts a symmetric ocean. You can even see parts of the MOR are leading under the north american continent.


    Since the growth ofthe Pacific used to occur by addition of new ocean floor at itsperiphery, we can predict that the zodiac fan which is shown on thefirst figure, must have been initially in the gulf of Alaska alongthe coast, and got displaced from the gulf by the accretion of newocean floor along the continental margin. The analysis made byStevenson confirmed an alasakan origin of the sediments forming thefan (Stevenson et al (1983) GSA Bull 94 p259-273).


    By contrast, platetectonics predicts that at the time to its formation, the fan shouldhave been 1500 km away from any continental source with a ridge(Pacific/Farallon) separating it from North America:
    Now you are wrong the shortening of the crust was mainly eastern of this fan, at the western north american coast there are many “terranes” proofed which had been lying in the mid of the former pacific ocean and then got accreted by the north american continent, those terranes are set apart from the continent by a completely different flora and fauna and that at the same latitude so there had to be a greater distance between those parts of continental crust. So such a terran could have been there also before 40 Ma without making any relative motion to this fan.


    Is that because convergence rates are deduced from spreading rates like in modelslike Nuvel1A?
    I don't know this model Nuvel1A. Satellite datais showing us that in most cases (I'm using your picture) the speed of a in direction to b and c is greater than the ridge expansion between b and c.


    Quote Originally Posted by florian View Post
    Tristan da Cuhna is a volcanic island on a plume track. I don't understandyour point? Why would supercontinent break if not because heat accumulates beneath them?
    the track of Tristan da Cunha is leading to a place called Parana and on the other site Etendeka in both places you find flood basalts, which are interpreted to have been the head of the plume. So this is one of the places (the most clearest place) where africa and america were split into two continents. The model about I told you that sees plumes as rising up recycled crust, doesn't need that accumulation.


    Quote Originally Posted by TheGeographer View Post
    by the way if you have a heated up upper mantlethat would be a barrier for all bottom-up dynamics, what I’marguing for. A cooled upper mantle would be advantageous for deepmantle plumes but they are not necessary so you wouldn’t need asuch big plume head to declare large igneous zones like in Siberiafor example.
    OK. I think that what would be advantageous for deep mantle plumes is smooth temperature gradient from the core to the lithosphere.
    ...of course, thats a consequence resulting from conductive heat flow being very inefficent, as a consequence I hoped to show you there have to be plumes.


    Well, thisis not what Asahara & Ohtani 2001 are arguing. How do you counter their arguments?
    well how are they arguing? I have no access to this paper. The paper I'm arguing about is of 2011(Start of the Wilson Cycle at 3 Ga Shown by Diamonds from Subcontinental Mantle) maybe they just didn't know.


    I barely understandyour argument. The lithosphere does not convect
    but the fluids
    If I followyour argument, how much heat would be transported by fluids and howdoes it compare to the heat flow? I've never seen that fluids aretaken into account in the estimation of the global output.
    Idon't know, probably no one knows, it's hardto say, maybe it's hard to measure I don't exactly know why there arethose big gaps of knowledge in this case. Fact is that you getproblems when you take a look at young granits being near the surfaceand measuring their temperature you can't declare the heat loss onlywith conductive heat flow, but how deep or how fast even how theylost the heat hard proof.


    That is a currentpicture. I said that the emplacements took place from the earlycretaceous to the miocene.
    cretaceous? Then the himalaya would't be the highest orogen in the world.
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    Quote Originally Posted by The Geographer View Post
    A process which is, seen nowhere else?! and not seen active happening?! It also predicts a symmetric ocean. You can even see parts of the MOR are leading under the north american continent.
    This process was seen all around the pacific, that is a large bit! It predicts the symmetry observed in the oldest part of the pacific. A tree-ring like pattern.
    You can see parts of a MOR emerging from under the north american continent. Remember, the ridge in the gulf of california is *brand new*, he did not connect with the EPR yet.


    Quote Originally Posted by The Geographer View Post
    Now you are wrong the shortening of the crust was mainly eastern of this fan, at the western north american coast there are many “terranes” proofed which had been lying in the mid of the former pacific ocean and then got accreted by the north american continent, those terranes are set apart from the continent by a completely different flora and fauna and that at the same latitude so there had to be a greater distance between those parts of continental crust. So such a terran could have been there also before 40 Ma without making any relative motion to this fan.
    What are you talking about? The fan is on the pacific lithosphere and plate tectonics predicts that there was a ridge to the east of the fan and then the farallon plate sliding under north america. The farallon plate not terranes!

    Quote Originally Posted by The Geographer View Post
    Is that because convergence rates are deduced from spreading rates like in modelslike Nuvel1A?
    I don't know this model Nuvel1A. Satellite datais showing us that in most cases (I'm using your picture) the speed of a in direction to b and c is greater than the ridge expansion between b and c.
    Nuvel 1A is the plate tectonics kinetic model. How is it possible that you don't know it??? Here is a lecture about it: http://seismo.berkeley.edu/~rallen/e...ctures/L04.pdf

    Could you show me one example of these GPS data you are talking about? We need a dense grid of stations including the back-arc and the subducted lithosphere just across the trench to see that, like what is available in the mediterranean sea or in Japan.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Tristan da Cuhna is a volcanic island on a plume track. I don't understandyour point? Why would supercontinent break if not because heat accumulates beneath them?
    the track of Tristan da Cunha is leading to a place called Parana and on the other site Etendeka in both places you find flood basalts, which are interpreted to have been the head of the plume. So this is one of the places (the most clearest place) where africa and america were split into two continents. The model about I told you that sees plumes as rising up recycled crust, doesn't need that accumulation.
    OK, I got it. So you say that continents initially weaken and break because of mantle upwelling (like in the afar or the east african rift system). I reassure you, this interpretation is shared by the auxotectonics model. BTW, I don't like much the term expansion, it is not accurate enough, so let me use this neologism.
    I guess that the heat accumulation hypothesis belongs to the top-down geoscientists like Foulger and Anderson.


    Quote Originally Posted by The Geographer View Post
    ...of course, thats a consequence resulting from conductive heat flow being very inefficent, as a consequence I hoped to show you there have to be plumes.
    You don't need to convince me. Mantle upwelling are expected, and even required in the auxotectonics model. This is how matter accumulating inside planets redistribute toward their surface. But the upwelling are much more diverse in auxotectonics, because they can be of thermal origin or composition origin or a mix. Depending on their nature they would reach the surface and become mantle flow as seen along active margins and orogenic region, or find their isostatic equilibrium at depth, leading to lateral of the layers located above them and eventually leading to rifting of the lithosphere, followed by ridge spreading. These are the basic principles of auxotectonics.


    Quote Originally Posted by The Geographer View Post
    Well, this is not what Asahara & Ohtani 2001 are arguing. How do you counter their arguments?
    well how are they arguing? I have no access to this paper. The paper I'm arguing about is of 2011(Start of the Wilson Cycle at 3 Ga Shown by Diamonds from Subcontinental Mantle) maybe they just didn't know.
    That make sense, since it was published 10 years later
    Awtually, that paper by Asahara & Ohtani is not the most relevant one because the propose a mix model. I should have not cite it. Parman 2004 is more relevant (Earth and Planetary Science Letters 219 (2004) 173-187). Or this text by the same Parman at mantle plume: Komatiites


    Quote Originally Posted by The Geographer View Post
    If I followyour argument, how much heat would be transported by fluids and howdoes it compare to the heat flow? I've never seen that fluids aretaken into account in the estimation of the global output.
    Idon't know, probably no one knows, it's hardto say, maybe it's hard to measure I don't exactly know why there arethose big gaps of knowledge in this case. Fact is that you getproblems when you take a look at young granits being near the surfaceand measuring their temperature you can't declare the heat loss onlywith conductive heat flow, but how deep or how fast even how theylost the heat hard proof.
    OK, I'm well aware that we don't know everything yet. But if the heat transported by fluids is very significant, that is certainly a big flaw in the methods used to calculate the radiogenic element content of Earth, mostly based on these heat flow calculations.

    Quote Originally Posted by The Geographer View Post
    That is a currentpicture. I said that the emplacements took place from the earlycretaceous to the miocene.
    cretaceous? Then the himalaya would't be the highest orogen in the world.
    I'm talking about the emplacements of the terranes now forming the tibetan plateau, not specifically about the formation of the Himalaya.
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    Quote Originally Posted by florian View Post
    This process was seen all around the pacific, that is a large bit! It predicts the symmetry observed in the oldest part of the pacific. A tree-ring like pattern.
    You can see parts of a MOR emerging from under the north american continent. Remember, the ridge in the gulf of california is *brand new*, he did not connect with the EPR yet.
    In the north of this you’ve got another piece of a MOR and the transform faults are leading under the continent.

    What are you talking about? The fan is on the pacific lithosphere and plate tectonics predicts that there was a ridge to the east of the fan and then the farallon plate sliding under north america. The farallon plate not terranes!
    Right, but nobody said until now that this material had to come from the farallon plate, even in the paper you cited not the farallon plate but Alaska was mentioned as source for the material of this fan and it also seems to me that the source for this fan came rather from NNE than from the east.

    Nuvel 1A is the plate tectonics kinetic model. How is it possible that you don't know it??? Here is a lecture about it: http://seismo.berkeley.edu/~rallen/e...ctures/L04.pdf

    Could you show me one example of these GPS data you are talking about? We need a dense grid of stations including the back-arc and the subducted lithosphere just across the trench to see that, like what is available in the mediterranean sea or in Japan.
    Ok seems to be that you are right and the speed is just calculated out of the spreading rates, Frisch & Meschede don’t cite any sources, but then you will have to declare Hawaii and the emperor chain.

    You didn’t comment my proofs for a large distance between the terrans by flora and fauna, I would like to add, this is also working with palaeomagnetic data at least if there was a motion in north south direction.

    Quote Originally Posted by florian View Post
    OK, I got it. So you say that continents initially weaken and break because of mantle upwelling (like in the afar or the east african rift system). I reassure you, this interpretation is shared by the auxotectonics model.
    Yes and no. The examples you cite seem to me to be passive driven by plate tectonics, meaning that with the expansation of the atlantic there was an impulse and then the eastern part of the continent kept speed but now this part is slowing down spreading rates are slowing down. Mean point of this way of argumentation is that the spreading rate in the south is much bigger than in the north (which is adequate with the whole African motion in the last 200 Ma which made a counterclockwise rotation) although you have got in the north and in the middle the typical rift volcanism like karbonatits (but no large igneous province). I don’t know afar that good, I don’t see there a real upwelling… maybe it’s passive, too… maybe it’s driven away from the upwelling, maybe the upwelling wasn’t strong enough, for both.

    BTW, I don't like much the term expansion, it is not accurate enough, so let me use this neologism.
    Ok I will mind this

    I guess that the heat accumulation hypothesis belongs to the top-down geoscientists like Foulger and Anderson.
    surely, but I also see the possibility that heat accumulation could be found under the transition zone and maybe this just needs just to be triggered by the rising recycled crust.

    You don't need to convince me. Mantle upwelling are expected, and even required in the auxotectonics model. This is how matter accumulating inside planets redistribute toward their surface. But the upwelling are much more diverse in auxotectonics, because they can be of thermal origin or composition origin or a mix.
    Oo plumes are always a mix in which heat or the composition (fluids) is mainly triggering the rising up, there is also a term which is adequate so we don’t only talk of hotspots additional we talk about wetspots.

    Depending on their nature they would reach the surface and become mantle flow as seen along active margins and orogenic region, or find their isostatic equilibrium at depth, leading to lateral of the layers located above them and eventually leading to rifting of the lithosphere, followed by ridge spreading. These are the basic principles of auxotectonics.
    well this theoretical possibility is also given in plate tectonics, I read something like this as suppose to declare “high” Africa (I hope this term is common in english) but you also have there the Geoid anomaly which isn’t given in the Himalaya.

    That make sense, since it was published 10 years later
    Awtually, that paper by Asahara & Ohtani is not the most relevant one because the propose a mix model. I should have not cite it. Parman 2004 is more relevant (Earth and Planetary Science Letters 219 (2004) 173-187). Or this text by the same Parman at mantle plume: Komatiites

    Hard theme, Frisch & Meschede are also talking about this they cite a paper from 1984 in which a crustal component was chemically proofed I don’t know if this is still the point of knowledge I even don’t agree with the model of Frisch & Meschede, another source is saying that the two komatiit types have there chemically difference from a fractionation of garnet this would indicate a relative deep melting source, maybe a subducted slab triggered by it’s high density and it’s additional isolating effect a plume… I just can specalute but I know it can’t have looked like the models I’ve seen till now. Maybe we open a new thread for this theme and discuss it later, I didn’t had the time to read what’s necessary.

    OK, I'm well aware that we don't know everything yet. But if the heat transported by fluids is very significant, that is certainly a big flaw in the methods used to calculate the radiogenic element content of Earth, mostly based on these heat flow calculations.
    …the calculations I know are based on chondrits or on K/U ratios derived from crustal rock for example McKenzie & Weiss, 1975.

    I'm talking about the emplacements of the terranes now forming the tibetan plateau, not specifically about the formation of the Himalaya.
    Plate tectonics even sees ways and possibilities which might be very similar to your models of the forming of the landscape its just called crustal creep (I don’t know the exact english word for this maybe it’s sliding instead of creep)

    Additional I found an article which may interest you it’s about paleomagnetic evidence for earths radius about the last 400 Ma it lay always between 99 and 105% of today that’s inclusive measurement inaccuracy (source Kearey: global tectonics. 3rd edition, 2008. P. 380f), I also found a paper about spreading rates till 150 Ma http://courses.washington.edu/ocean4...perplume_I.pdf (didn‘t read it yet)
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  4. #404  
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    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    This process was seen all around the pacific, that is a large bit! It predicts the symmetry observed in the oldest part of the pacific. A tree-ring like pattern.
    You can see parts of a MOR emerging from under the north american continent. Remember, the ridge in the gulf of california is *brand new*, he did not connect with the EPR yet.
    In the north of this you’ve got another piece of a MOR and the transform faults are leading under the continent.
    Yes, the Juan de Fuca MOR is also a new MOR that is just 10 My old or so and it formed from under the active margin. You can picture it as a reversal in time of a ridge subduction. The transform fault system connecting the the Juan the Fuca ridge and the gulf of california ridge is predicted to evolve into a ridge as well. So in 10 My or so, we will get a continuous ridge extending from Alaska to Antarctica.

    Quote Originally Posted by The Geographer View Post
    What are you talking about? The fan is on the pacific lithosphere and plate tectonics predicts that there was a ridge to the east of the fan and then the farallon plate sliding under north america. The farallon plate not terranes!
    Right, but nobody said until now that this material had to come from the farallon plate, even in the paper you cited not the farallon plate but Alaska was mentioned as source for the material of this fan and it also seems to me that the source for this fan came rather from NNE than from the east.
    This is exactly the point: The material came from Alaska in the NNE. This implies that the fan did not move northward as predicted over thousands km as predicted from plates tectonics. Indeed, the fan is on the pacific plate which is predicted to have move northward during the last 60 millions years or so. I think that you understand the paradox.
    By comparison, the auxotectonics model predicts that according to the age of seafloor, the fan formed to the NNE, along the margin of Alaska. The prediction matches the data in this case.


    Quote Originally Posted by The Geographer View Post
    You didn’t comment my proofs for a large distance between the terrans by flora and fauna, I would like to add, this is also working with palaeomagnetic data at least if there was a motion in north south direction.
    This is the kind of motion that was predicted by Carey but of opposite sides of a megashear. Carey predicted a megashear along which the two sides passed each other and get offset by thousands km, hence the difference in fauna flora and paleomagnetic.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    OK, I got it. So you say that continents initially weaken and break because of mantle upwelling (like in the afar or the east african rift system). I reassure you, this interpretation is shared by the auxotectonics model.
    Yes and no. The examples you cite seem to me to be passive driven by plate tectonics, meaning that with the expansation of the atlantic there was an impulse and then the eastern part of the continent kept speed but now this part is slowing down spreading rates are slowing down. Mean point of this way of argumentation is that the spreading rate in the south is much bigger than in the north (which is adequate with the whole African motion in the last 200 Ma which made a counterclockwise rotation) although you have got in the north and in the middle the typical rift volcanism like karbonatits (but no large igneous province). I don’t know afar that good, I don’t see there a real upwelling… maybe it’s passive, too… maybe it’s driven away from the upwelling, maybe the upwelling wasn’t strong enough, for both.
    There was doming (2 domes) at the origin of the lake rift system to the south, and the Afar/Red Sea/Gulf of Aden triple junction to the north. It is well established in the literature.
    Your remark about the origin of the rotation of Africa (larger spreading rate in the south) is perfectly right. It is also predicted by the auxotectonics model because the growth is larger in the southern hemisphere, and thus fastest spreading rate are found there for every ridge at about 30°S as you can see on this figure.





    Quote Originally Posted by The Geographer View Post
    You don't need to convince me. Mantle upwelling are expected, and even required in the auxotectonics model. This is how matter accumulating inside planets redistribute toward their surface. But the upwelling are much more diverse in auxotectonics, because they can be of thermal origin or composition origin or a mix.
    Oo plumes are always a mix in which heat or the composition (fluids) is mainly triggering the rising up, there is also a term which is adequate so we don’t only talk of hotspots additional we talk about wetspots.
    OK.

    Depending on their nature they would reach the surface and become mantle flow as seen along active margins and orogenic region, or find their isostatic equilibrium at depth, leading to lateral of the layers located above them and eventually leading to rifting of the lithosphere, followed by ridge spreading. These are the basic principles of auxotectonics.
    well this theoretical possibility is also given in plate tectonics, I read something like this as suppose to declare “high” Africa (I hope this term is common in english) but you also have there the Geoid anomaly which isn’t given in the Himalaya.[/QUOTE]
    OK. Actually there is a geoid anomaly but for the tibetan plateau, which makes more sense than for the himalayas that are just napes pushed over india by the plateau.


    You don't need to convince me. Mantle upwelling are expected, and even required in the auxotectonics model. This is how matter accumulating inside planets
    That make sense, since it was published 10 years later
    Awtually, that paper by Asahara & Ohtani is not the most relevant one because the propose a mix model. I should have not cite it. Parman 2004 is more relevant (Earth and Planetary Science Letters 219 (2004) 173-187). Or this text by the same Parman at mantle plume: Komatiites
    Hard theme, Frisch & Meschede are also talking about this they cite a paper from 1984 in which a crustal component was chemically proofed I don’t know if this is still the point of knowledge I even don’t agree with the model of Frisch & Meschede, another source is saying that the two komatiit types have there chemically difference from a fractionation of garnet this would indicate a relative deep melting source, maybe a subducted slab triggered by it’s high density and it’s additional isolating effect a plume… I just can specalute but I know it can’t have looked like the models I’ve seen till now. Maybe we open a new thread for this theme and discuss it later, I didn’t had the time to read what’s necessary.
    OK.

    Quote Originally Posted by The Geographer View Post
    OK, I'm well aware that we don't know everything yet. But if the heat transported by fluids is very significant, that is certainly a big flaw in the methods used to calculate the radiogenic element content of Earth, mostly based on these heat flow calculations.
    …the calculations I know are based on chondrits or on K/U ratios derived from crustal rock for example McKenzie & Weiss, 1975.
    Yes that's right, the global heat flow is actually compared to that estimated from the decay of U and K and the difference is assumed to be the residual heat from accretion. I had in mind an old review by Davies (1980) Review of Oceanic and Global Heat Flow Estimates. I did not remember that, Davies cites an estimate of the Heat Flow from hydrothermal circulations (Langseth and Anderson 1979 JGR 84, p1139). That accounts for 25% of the global heat flow. So hydrothermal related heat flow is part of the estimate.

    Quote Originally Posted by The Geographer View Post
    I'm talking about the emplacements of the terranes now forming the tibetan plateau, not specifically about the formation of the Himalaya.
    Plate tectonics even sees ways and possibilities which might be very similar to your models of the forming of the landscape its just called crustal creep (I don’t know the exact english word for this maybe it’s sliding instead of creep)
    That would be creep, for the tibetan plateau, I think that the model I'm talking about is more related to crustal thickening by underplating.

    Quote Originally Posted by The Geographer View Post
    Additional I found an article which may interest you it’s about paleomagnetic evidence for earths radius about the last 400 Ma it lay always between 99 and 105% of today that’s inclusive measurement inaccuracy (source Kearey: global tectonics. 3rd edition, 2008. P. 380f),
    That is p382
    McElhinny used Ward's method to calculated paleoradius, and this method are flawed as shown by Carey and Chudinov.
    I don't know a single method that refutes the growth of earth that has no deep flow, and believe, I study them all.

    Quote Originally Posted by The Geographer View Post
    I also found a paper about spreading rates till 150 Ma http://courses.washington.edu/ocean4...perplume_I.pdf (didn‘t read it yet)
    p548, 2nd column, 2nd paragraph, they say they assume the symmetric spreading of ridges for the pacific for the last 150 My. And I argued above why this is a wrong assumption. So this paper goes right to the trash.
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    Quote Originally Posted by florian View Post
    Yes, the Juan de Fuca MOR is also a new MOR that is just 10 My old or so and it formed from under the active margin. You can picture it as a reversal in time of a ridge subduction. The transform fault system connecting the the Juan the Fuca ridge and the gulf of california ridge is predicted to evolve into a ridge as well.
    I don’t think that there is a extensional motion between Baja California and the continent, I think it’s just because of the still a little bit upwelling mantle that’s one of the few regions on the west american coast where is no subduction!

    Quote Originally Posted by florian View Post
    This is exactly the point: The material came from Alaska in the NNE. This implies that the fan did not move northward as predicted over thousands km as predicted from plates tectonics. Indeed, the fan is on the pacific plate which is predicted to have move northward during the last 60 millions years or so.
    Who is predicting this? I never heard about that? And it even doesn’t agree with the Hawaiian hotspot track. And please no paper which is older than 20 years.

    Quote Originally Posted by florian View Post
    There was doming (2 domes) at the origin of the lake rift system to the south, and the Afar/Red Sea/Gulf of Aden triple junction to the north. It is well established in the literature.
    Your remark about the origin of the rotation of Africa (larger spreading rate in the south) is perfectly right. It is also predicted by the auxotectonics model because the growth is larger in the southern hemisphere, and thus fastest spreading rate are found there for every ridge at about 30°S as you can see on this figure.
    yes but keep in mind that in the northwestern of Africa there is the oldest oceanic crust with an age about 185 Ma this should be the oldest in the 3 big oceans. In Plate tectonics you can even declare this with the inhomogenous ridge push on the south American coast.

    OK. Actually there is a geoid anomaly but for the tibetan plateau, which makes more sense than for the himalayas that are just napes pushed over india by the plateau.
    http://op.gfz-potsdam.de/champ/resul...champ03s_u.jpg I admit that arguing about this will probably will not bring us further. What about the paper I send you? By the way how should this from beneath accreted… plate(?) look like? Are there any such plates anywhere lying at the surface? Or has every continent been created like this? And why are there volcanoes and erathquakes at subduction zones if there is no subduction?

    I don't know a single method that refutes the growth of earth that has no deep flow, and believe, I study them all.
    If something is not refuted doesn't mean that it is congruent with reality. You will also get problems to declare what was there before pangea? why should have ocean floor spreading been nearly zero.
    Last edited by The Geographer; January 10th, 2012 at 09:42 PM.
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    Quote Originally Posted by The Geographer View Post
    I don’t think that there is a extensional motion between Baja California and the continent, I think it’s just because of the still a little bit upwelling mantle that’s one of the few regions on the west american coast where is no subduction!
    Oh yes, there is : Variation in styles of rifting in the Gulf of California

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    This is exactly the point: The material came from Alaska in the NNE. This implies that the fan did not move northward as predicted over thousands km as predicted from plates tectonics. Indeed, the fan is on the pacific plate which is predicted to have move northward during the last 60 millions years or so.
    Who is predicting this? I never heard about that? And it even doesn’t agree with the Hawaiian hotspot track. And please no paper which is older than 20 years.
    You can see where the fan was at the time of deposition (40-32 Ma) on this video:


    Do you agree that the current position of this fan refutes plate tectonics as a whole?

    Quote Originally Posted by The Geographer View Post
    yes but keep in mind that in the northwestern of Africa there is the oldest oceanic crust with an age about 185 Ma this should be the oldest in the 3 big oceans. In Plate tectonics you can even declare this with the inhomogenous ridge push on the south American coast.
    What do you mean? I do not see any link with the rotation of Africa?

    Quote Originally Posted by The Geographer View Post
    OK. Actually there is a geoid anomaly but for the tibetan plateau, which makes more sense than for the himalayas that are just napes pushed over india by the plateau.
    http://op.gfz-potsdam.de/champ/resul...champ03s_u.jpg I admit that arguing about this will probably will not bring us further.
    You can see the tibetan plateau on the figure because it is an anomaly compared to what is around.

    Quote Originally Posted by The Geographer View Post
    What about the paper I send you?
    The conclusion of the paper you send me are not different that what I've read elsewhere. The tibetan lithosphere overrides the asian lithosphere to the north and the Indian lithosphere to the south.


    Quote Originally Posted by The Geographer View Post
    By the way how should this from beneath accreted… plate(?) look like? Are there any such plates anywhere lying at the surface? Or has every continent been created like this?
    Yes, by arc accretion, underplating, uplift, intrusions... nothing special.


    Quote Originally Posted by The Geographer View Post
    And why are there volcanoes and erathquakes at subduction zones if there is no subduction?
    There is subduction, but mantle driven. I thought my earlier scheme was clear enough? The origin of volcanoes and earthquakes does not change whether subduction is mantle driven or slab driven. Mantle-driven subduction could be called something like overduction.

    Quote Originally Posted by The Geographer View Post
    I don't know a single method that refutes the growth of earth that has no deep flaw, and believe me, I study them all.
    If something is not refuted doesn't mean that it is congruent with reality. You will also get problems to declare what was there before pangea? why should have ocean floor spreading been nearly zero.
    The ocean floor spreading rate of the "modern oceans" was near zero, but there were other basins. Also the growth was much slower and it is predicted that the basins were narrower and rapidly filled by sediments.
    The configuration of the cratons around australia at the time the pacific was closed is that determined empirically in support of Rodinia.
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    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    I don’t think that there is a extensional motion between Baja California and the continent, I think it’s just because of the still a little bit upwelling mantle that’s one of the few regions on the west american coast where is no subduction!
    Oh yes, there is : Variation in styles of rifting in the Gulf of California
    there is also standing: "The peninsula now moves nearly completely with the Pacific plate, with 48 mm yr-1 of spreading across the Gulf of California representing 92% of Pacific–North America relative motion"


    Quote Originally Posted by florian View Post
    You can see where the fan was at the time of deposition (40-32 Ma) on this video:
    ok there are a couple of points I have to mention:
    1. you rather ment one thousand and not thousands of kilometers, what you even can't see out of this video because they didn't took a equal-area projection
    2. did you take one model out of... I don't know how many there are but surley it isn't the only one.
    3. are there no terranes, which could have changed there position to this fan hardly,
    4. the source of this fan had to lay more south of course! Why? Where and when do you have enough amount of water to create such a fan? after glacials where do you have such fans? rather south where you have got the most ice melting.


    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    yes but keep in mind that in the northwestern of Africa there is the oldest oceanic crust with an age about 185 Ma this should be the oldest in the 3 big oceans. In Plate tectonics you can even declare this with the inhomogenous ridge push on the south American coast.
    What do you mean? I do not see any link with the rotation of Africa?
    ok take a look at the image important is that the image doesn't show one point of time (but I didn't want to paint 3 or 4 images) the images is evolvin in time from the west to the east. In the west I predicted a MOR which is in the north nearer to south america than in the south => the ridge push is in the north bigger and so the north slows down while the south kept speed (or the south got faster and the north kept speed). As a consequence out of this in the atlantic the spreading rates are in the south are bigger which now pushes africa in its counter clockwise motion. Nowadays the MOR in front of whole south america is nearly parallel to the coast the MOR in the atlantic is spreading in north and south quite similar as a consequence the east african rift results what I already decared to you.
    Plattentektonik.jpg


    Quote Originally Posted by florian View Post
    The conclusion of the paper you send me are not different that what I've read elsewhere. The tibetan lithosphere overrides the asian lithosphere to the north and the Indian lithosphere to the south.
    if you argue like that there cannot be metamorphic rocks in mountains, but there are!


    Quote Originally Posted by florian View Post
    By the way how should this from beneath accreted… plate(?) look like? Are there any such plates anywhere lying at the surface? Or has every continent been created like this?
    Yes, by arc accretion, underplating, uplift, intrusions... nothing special.[/Quote] the point is that there is no chemical signal that the plates come out of the mantle, all you find is typical crustal material which is also much to old to have been created out of this.


    Quote Originally Posted by florian View Post
    There is subduction, but mantle driven. I thought my earlier scheme was clear enough? The origin of volcanoes and earthquakes does not change whether subduction is mantle driven or slab driven. Mantle-driven subduction could be called something like overduction.
    ok but what happens with this material? And why shouldn't it have been there before (you argued that the spreading rate of the pacific would have been nearly zero before 200 Ma) And by the way you're denying the fact that the density of old oceanic crust is higher than mantle density.


    The ocean floor spreading rate of the "modern oceans" was near zero, but there were other basins. Also the growth was much slower and it is predicted that the basins were narrower and rapidly filled by sediments.
    there are also proofs for very wide basins in the case of the indian and the asian plate for example


    The configuration of the cratons around australia at the time the pacific was closed is that determined empirically in support of Rodinia.
    I don't know if I don't understand you because of your argument or because of the language... what exactly do you mean with "is that determined empirically in support of Rodinia"
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    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Oh yes, there is : Variation in styles of rifting in the Gulf of California
    there is also standing: "The peninsula now moves nearly completely with the Pacific plate, with 48 mm yr-1 of spreading across the Gulf of California representing 92% of Pacific–North America relative motion"
    See, there is extension there. As I stated earlier, this will lead to the propagation of the ridge through the San Andreas fault system.


    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    You can see where the fan was at the time of deposition (40-32 Ma) on this video:
    ok there are a couple of points I have to mention:
    1. you rather ment one thousand and not thousands of kilometers, what you even can't see out of this video because they didn't took a equal-area projection
    1500 km to the west of any terrane. Mollweide is a equal-area projection.

    Quote Originally Posted by The Geographer View Post
    2. did you take one model out of... I don't know how many there are but surley it isn't the only one.
    You can't get better model than those based on the age of seafloor because they include the whole history of the oceans. This one was published in Science.

    Quote Originally Posted by The Geographer View Post
    3. are there no terranes, which could have changed there position to this fan hardly,
    The terranes from which the fan sediments come are identified as being Alaska terranes. I sent you the paper by email.


    Quote Originally Posted by The Geographer View Post
    4. the source of this fan had to lay more south of course! Why? Where and when do you have enough amount of water to create such a fan? after glacials where do you have such fans? rather south where you have got the most ice melting.
    Yes, the drainage area was huge, about 500,000 km2.


    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    yes but keep in mind that in the northwestern of Africa there is the oldest oceanic crust with an age about 185 Ma this should be the oldest in the 3 big oceans. In Plate tectonics you can even declare this with the inhomogenous ridge push on the south American coast.
    What do you mean? I do not see any link with the rotation of Africa?
    ok take a look at the image important is that the image doesn't show one point of time (but I didn't want to paint 3 or 4 images) the images is evolvin in time from the west to the east. In the west I predicted a MOR which is in the north nearer to south america than in the south => the ridge push is in the north bigger and so the north slows down while the south kept speed (or the south got faster and the north kept speed). As a consequence out of this in the atlantic the spreading rates are in the south are bigger which now pushes africa in its counter clockwise motion. Nowadays the MOR in front of whole south america is nearly parallel to the coast the MOR in the atlantic is spreading in north and south quite similar as a consequence the east african rift results what I already decared to you.
    This description does not correspond to the real situation. All the ridges have greater spreading rate in the south. Besides the geometry of the ridges in the pacific is a bit more complex than what your scheme suggests. You could eventually use a Mollweide projection to illustrate your point:





    One more thing. If you look carefully at the latitude 20°S, there is actually 6 consecutive extension zones.
    From west to east: The altiplano, the MAR, the east african rift system, the indian ocean ridge, the Fiji basin, the Tonga basin.
    So what is pushing what?


    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    The conclusion of the paper you send me are not different than what I've read elsewhere. The tibetan lithosphere overrides the asian lithosphere to the north and the Indian lithosphere to the south.
    if you argue like that there cannot be metamorphic rocks in mountains, but there are!
    I don't understand why? Diapirism or shear stress explains metamorphism very well.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    By the way how should this from beneath accreted… plate(?) look like? Are there any such plates anywhere lying at the surface? Or has every continent been created like this?
    Yes, by arc accretion, underplating, uplift, intrusions... nothing special.
    The point is that there is no chemical signal that the plates come out of the mantle, all you find is typical crustal material which is also much to old to have been created out of this.
    I don't understand. This is the classical description for the formation of the tibetan terranes. Do you disagree with it? why?
    And I do not understand the statement; "plates coming out of the mantle". What do you mean by plate? The tibetan terranes?

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    There is subduction, but mantle driven. I thought my earlier scheme was clear enough? The origin of volcanoes and earthquakes does not change whether subduction is mantle driven or slab driven. Mantle-driven subduction could be called something like overduction.
    ok but what happens with this material? And why shouldn't it have been there before (you argued that the spreading rate of the pacific would have been nearly zero before 200 Ma)
    What material? The arc material? Could you be more specific, I don't understand your question.

    Quote Originally Posted by The Geographer View Post
    And by the way you're denying the fact that the density of old oceanic crust is higher than mantle density.
    Why would I deny that? If it was not dense enough, it would not sink under the load of the mantle.

    Quote Originally Posted by The Geographer View Post
    The ocean floor spreading rate of the "modern oceans" was near zero, but there were other basins. Also the growth was much slower and it is predicted that the basins were narrower and rapidly filled by sediments.
    there are also proofs for very wide basins in the case of the indian and the asian plate for example
    Look carefully at the data without any interpretation. All you have is a narrow ophiolitic suture, may be not more than 50 km wide. That makes hardly a "wide ocean".

    Quote Originally Posted by The Geographer View Post
    The configuration of the cratons around australia at the time the pacific was closed is that determined empirically in support of Rodinia.
    I don't know if I don't understand you because of your argument or because of the language... what exactly do you mean with "is that determined empirically in support of Rodinia"
    Geological/Geochemical/paleomagnetical data are used to constraint the relative position of cratons at the time of rodinia. The relative positions of the cratons derived from these data match the prediction of the expanding earth theory at the time when the pacific was not yet open. Less the contradiction of the tectonics models (mutual exclusion of SWEAT and AUSWUS models of Rodinia), because on a smaller earth, cratons can be geometrically closer to each others. There exists an equivalent paradox with reconstructions around antartica.
    Last edited by florian; January 16th, 2012 at 03:15 PM.
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    After passed exams let's go on

    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Oh yes, there is : Variation in styles of rifting in the Gulf of California
    there is also standing: "The peninsula now moves nearly completely with the Pacific plate, with 48 mm yr-1 of spreading across the Gulf of California representing 92% of Pacific–North America relative motion"
    See, there is extension there. As I stated earlier, this will lead to the propagation of the ridge through the San Andreas fault system.
    yes but local expansion is not prohibited you also got local expansion by crustal creeping in China near the Himalaya you even have their graben structures, although the whole movement is like I said compressional not extensional. I send you a picture out of Frisch and Meschede about this point.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    You can see where the fan was at the time of deposition (40-32 Ma) on this video:
    ok there are a couple of points I have to mention:
    1. you rather ment one thousand and not thousands of kilometers, what you even can't see out of this video because they didn't took a equal-area projection
    1500 km to the west of any terrane. Mollweide is a equal-area projection.
    ok it didn’t look like an equal area projection… maybe my view on the world is a little bit false. Ok than 1500 km

    Quote Originally Posted by The Geographer View Post
    3. are there no terranes, which could have changed there position to this fan hardly,
    The terranes from which the fan sediments come are identified as being Alaska terranes. I sent you the paper by email.
    Although this doesn’t matter my argument (cause this terrane could have changed it’s position together with the fan) in the paper you sent me is also mentioned that mineralogical the cascade range 1500km in the south could be also the source (but this was unlikely to this point of time) maybe the reconstruction of the pacific plate motion just minded information out of this fan.

    This description does not correspond to the real situation. All the ridges have greater spreading rate in the south.
    surely cause you have got the most subduction here
    welcome to plate tectonic arguments!
    Besides the geometry of the ridges in the pacific is a bit more complex than what your scheme suggests. You could eventually use a Mollweide projection to illustrate your point:
    it’s just a scheme and it’s even not nowadays and it’s naturally simplifying things, that’s the point of schemes.

    One more thing. If you look carefully at the latitude 20°S, there is actually 6 consecutive extension zones.
    From west to east: The altiplano, the MAR, the east african rift system, the indian ocean ridge, the Fiji basin, the Tonga basin.
    So what is pushing what?
    you’re right, really hard to say. Also you mentioned there extension zones which are in their rates about, I don’t know exactly… is there even a extent spreading in the altiplano? The east African rift is slowing down, Tonga and Fiji this should be Back-Arcs, aren’t they?


    Quote Originally Posted by florian View Post
    I don't understand why? Diapirism or shear stress explains metamorphism very well.
    ok maybe I was a little bit to fast. But you forget the final point of metamorphism if it would be like you said it there only would be retrograd metamorphism this stones would lie on the surface and everything should result out of magma, do you agree? (perhaps you first look one below)

    Quote Originally Posted by florian View Post
    I don't understand. This is the classical description for the formation of the tibetan terranes. Do you disagree with it? why?
    And I do not understand the statement; "plates coming out of the mantle". What do you mean by plate? The tibetan terranes?
    ok maybe I really understood you wrong than you can forget what I wrote above. Cause you always said this would be a major zone of expansion, didn’t you? I thought you say something like there is a creation of new terrane directly out of the mantle.

    Quote Originally Posted by florian View Post
    What material? The arc material? Could you be more specific, I don't understand your question.
    (subducted) oceanic crust

    Quote Originally Posted by The Geographer View Post
    And by the way you're denying the fact that the density of old oceanic crust is higher than mantle density.
    Why would I deny that? If it was not dense enough, it would not sink under the load of the mantle.
    but if this is so it’s plate (and not mantle) driven.

    Quote Originally Posted by The Geographer View Post
    The ocean floor spreading rate of the "modern oceans" was near zero, but there were other basins. Also the growth was much slower and it is predicted that the basins were narrower and rapidly filled by sediments.
    there are also proofs for very wide basins in the case of the indian and the asian plate for example
    Look carefully at the data without any interpretation. All you have is a narrow ophiolitic suture, may be not more than 50 km wide. That makes hardly a "wide ocean".[/quote] Unfortunately I have only a little opinion/knowledge about the flora and fauna proved in those sediments but everybody I know who writes about this sutures says that those sediments on the different sides had to be in greater distance to each other.

    Geological/Geochemical/paleomagnetical data are used to constraint the relative position of cratons at the time of rodinia. The relative positions of the cratons derived from these data match the prediction of the expanding earth theory at the time when the pacific was not yet open. Less the contradiction of the tectonics models (mutual exclusion of SWEAT and AUSWUS models of Rodinia), because on a smaller earth, cratons can be geometrically closer to each others. There exists an equivalent paradox with reconstructions around antartica.
    I've to look up something for this point, I think there is a new reconstruction...
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    Quote Originally Posted by The Geographer View Post
    After passed exams let's go on

    Quote Originally Posted by florian View Post
    See, there is extension there. As I stated earlier, this will lead to the propagation of the ridge through the San Andreas fault system.
    yes but local expansion is not prohibited you also got local expansion by crustal creeping in China near the Himalaya you even have their graben structures, although the whole movement is like I said compressional not extensional. I send you a picture out of Frisch and Meschede about this point.
    This is not a simple local expansion comparable to something like gravity sliding. This a a new rift evolving into ridge, not different that the one developing in the Red Sea.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    3. are there no terranes, which could have changed there position to this fan hardly,
    The terranes from which the fan sediments come are identified as being Alaska terranes. I sent you the paper by email.
    Although this doesn’t matter my argument (cause this terrane could have changed it’s position together with the fan) in the paper you sent me is also mentioned that mineralogical the cascade range 1500km in the south could be also the source (but this was unlikely to this point of time) maybe the reconstruction of the pacific plate motion just minded information out of this fan.
    Plate tectonics leaves no other choice than moving the pacific plate to the northwest while moving North america to the west. If you say that this is wrong (and I would agree) the the whole plate tectonics theory falls apart. Facts refute plate tectonics, plain and simple.


    Quote Originally Posted by The Geographer View Post
    it’s just a scheme and it’s even not nowadays and it’s naturally simplifying things, that’s the point of schemes.
    Schemes are ok as long as their simplification do not kill the purpose of the scheme.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    One more thing. If you look carefully at the latitude 20°S, there is actually 6 consecutive extension zones.
    From west to east: The altiplano, the MAR, the east african rift system, the indian ocean ridge, the Fiji basin, the Tonga basin.
    So what is pushing what?
    you’re right, really hard to say. Also you mentioned there extension zones which are in their rates about, I don’t know exactly… is there even a extent spreading in the altiplano? The east African rift is slowing down, Tonga and Fiji this should be Back-Arcs, aren’t they?
    They are back arc, i.e. extensions zones. The point is that these consecutive extension zones cover 70% of the latitude 20°C, and even better, the fastest extension zone of the planet is right in the middle of the 30% left. I let you think about it.

    Quote Originally Posted by florian View Post
    I don't understand why? Diapirism or shear stress explains metamorphism very well.
    ok maybe I was a little bit to fast. But you forget the final point of metamorphism if it would be like you said it there only would be retrograd metamorphism this stones would lie on the surface and everything should result out of magma, do you agree? (perhaps you first look one below)

    Quote Originally Posted by The Geographer View Post
    ok maybe I really understood you wrong than you can forget what I wrote above. Cause you always said this would be a major zone of expansion, didn’t you? I thought you say something like there is a creation of new terrane directly out of the mantle.
    I meant underplating, and yes, the tibetan plateau is a zone of expansion with subcrustal channels with high fluids contents flowing to the east.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    What material? The arc material? Could you be more specific, I don't understand your question.
    (subducted) oceanic crust
    The oceanic crust is overran by the arc, engulfed in the mantle, it releases its volatiles and so on... Why do you believe it has different effects than subduction?

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    And by the way you're denying the fact that the density of old oceanic crust is higher than mantle density.
    Why would I deny that? If it was not dense enough, it would not sink under the load of the mantle.
    but if this is so it’s plate (and not mantle) driven.
    No, if the was no load over the oceanic lithosphere, it would not sink. The facts, just the facts. The oldest Pacific/Atlantic/Indian Ocean lithosphere is certainly not sinking despite its age is about 170-180 Ma, even better for the eastern basin of the Mediterranean sea which oldest lithosphere is 280 My and is along Egypt.

    Quote Originally Posted by The Geographer View Post
    Look carefully at the data without any interpretation. All you have is a narrow ophiolitic suture, may be not more than 50 km wide. That makes hardly a "wide ocean".
    Unfortunately I have only a little opinion/knowledge about the flora and fauna proved in those sediments but everybody I know who writes about this sutures says that those sediments on the different sides had to be in greater distance to each other.
    On both side of the Yarlung-Zang Bo suture? What are these sediments. I must look at what they are and where their are. Do you have references?
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    I found this gem which is conclusive evidence in favour of plate tectonics, and firmly rules out the possibility of an expanding Earth:

    Zorin. Geodynamics of the western part of the Mongolia-Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia. Tectonophysics (1999) vol. 306 (1) pp. 33-56

    Geodynamics of the western part of the Mongolia?Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia 10.1016/S0040-1951(99)00042-6 : Tectonophysics | ScienceDirect.com
    Basically a lot of good solid geological evidence is synthesized to show in detail how Mongolia collided with Siberia. As a follow up to that there is this great little paper which shows the seismic evidence of the above process:

    Van der Voo et al. Mesozoic subducted slabs under Siberia. Nature (1999) vol. 397 (6716) pp. 246-249

    This one shows that there is a slab graveyard at the base of the mantle beneath Siberia.


    The blue in the above images shows fast seismic velocities. These are interpreted as the signature of subducting slabs going all the way down to the base of the mantle. In the tope diagram the blue to the left labelled M is the remnants of the ocean that was subducted when Mongolia collided with Siberia. The blue to the right labelled P is the remnants of subducted Pacific ocean slab material which was subducted beneath Japan. Japan is a very tectonically active place as is widely known the region is volcanically and seismically hazardous. The Pacific is still being subducted beneath Japan, as can be clearly seen by this lovely piece of work which looks more closely at the slab beneath Japan:

    Zhao. Global tomographic images of mantle plumes and subducting slabs: insight into deep Earth dynamics. Physics of the Earth and Planetary Interiors (2004)

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    This is not a simple local expansion comparable to something like gravity sliding. This a a new rift evolving into ridge, not different that the one developing in the Red Sea.

    It’s just another subducted MOR like the Japanese ocean. I formerly thought that such a slow spreading structure would be obducted like it happened once in cyprus, but maybe you’re not that bad like I thought until now, last month I talked to somebody who is searching for the former suture of Gondwana and it looks like that the Atlantic had been a former back arc basin (with the former suture lying on the south American east coast), so the upwelling would result out of a still upwelling mantle of a subducted MOR, but this suture also means that there had been a greater distance between those continents, they difference the source of the material by (to say it easy) dating it.

    Plate tectonics leaves no other choice than moving the pacific plate to the northwest while moving North america to the west. If you say that this is wrong (and I would agree) the the whole plate tectonics theory falls apart. Facts refute plate tectonics, plain and simple.
    You don’t mind any motion of the pacific plate. Didn’t you realize that your own movie about the plate movement of the pacific declares how this fan can be where it is?

    They are back arc, i.e. extensions zones. The point is that these consecutive extension zones cover 70% of the latitude 20°C, and even better, the fastest extension zone of the planet is right in the middle of the 30% left. I let you think about it.

    There are also great convergence zones (subduction zones/mountain belts), that doesn’t make any trouble in plate tectonics.

    No, if the was no load over the oceanic lithosphere, it would not sink. The facts, just the facts. The oldest Pacific/Atlantic/Indian Ocean lithosphere is certainly not sinking despite its age is about 170-180 Ma, even better for the eastern basin of the Mediterranean sea which oldest lithosphere is 280 My and is along Egypt.
    What do you mean by load? Another plate which overruns the subducted plate? Yes! Sedimentmaterial? No! It’s just a question of density not only weight… so you always need a plate.


    On both side of the Yarlung-Zang Bo suture? What are these sediments. I must look at what they are and where their are. Do you have references?
    No, this suture is interpreted as back-arc basin. Sutures of wide oceans doesn’t look like in books written (because the older oceanic lithosphere is in most cases subducted), so they are very hard to find (and like I wrote above they are in most times still not found today). Perhaps you also take a look at “Petrology and geochemistry of the Saga and Sangsang ophiolitic massifs, Yarlung Zangbo Suture Zone, Southern Tibet: Evidence for an arc–back-arc origin” (2009).
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    Quote Originally Posted by billiards View Post
    I found this gem which is conclusive evidence in favour of plate tectonics, and firmly rules out the possibility of an expanding Earth:

    Zorin. Geodynamics of the western part of the Mongolia-Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia. Tectonophysics (1999) vol. 306 (1) pp. 33-56

    Geodynamics of the western part of the Mongolia?Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia 10.1016/S0040-1951(99)00042-6 : Tectonophysics | ScienceDirect.com
    Basically a lot of good solid geological evidence is synthesized to show in detail how Mongolia collided with Siberia. As a follow up to that there is this great little paper which shows the seismic evidence of the above process:

    Van der Voo et al. Mesozoic subducted slabs under Siberia. Nature (1999) vol. 397 (6716) pp. 246-249

    This one shows that there is a slab graveyard at the base of the mantle beneath Siberia.

    Attributing every region of fast velocity zone to a slab does not make any sense. Fast velocities can be related to difference in composition, in phase...

    The slab under Japan is well defined thanx to earthquakes, but if you believe that it refutes Earth Expansion, then it means that you don't understand overthrusting.
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    Quote Originally Posted by The Geographer View Post
    This is not a simple local expansion comparable to something like gravity sliding. This a a new rift evolving into ridge, not different that the one developing in the Red Sea.

    It’s just another subducted MOR like the Japanese ocean.
    The Japanese ocean? Do you mean the sea of Japan? this is a marginal sea.

    Quote Originally Posted by The Geographer View Post
    I formerly thought that such a slow spreading structure would be obducted like it happened once in cyprus, but maybe you’re not that bad like I thought until now, last month I talked to somebody who is searching for the former suture of Gondwana and it looks like that the Atlantic had been a former back arc basin (with the former suture lying on the south American east coast), so the upwelling would result out of a still upwelling mantle of a subducted MOR, but this suture also means that there had been a greater distance between those continents, they difference the source of the material by (to say it easy) dating it.
    Upwelling can transport material over large distances. Plus the suture could be a shear zone with lateral offset of several thousand km.

    You don’t mind any motion of the pacific plate. Didn’t you realize that your own movie about the plate movement of the pacific declares how this fan can be where it is?
    The movie present the plate tectonic model. This model predicts that the fan originates in the middle of the Pacific far away from Alaska. We know that this is not true. So the plate tectonic model is refuted.

    Quote Originally Posted by The Geographer View Post
    They are back arc, i.e. extensions zones. The point is that these consecutive extension zones cover 70% of the latitude 20°C, and even better, the fastest extension zone of the planet is right in the middle of the 30% left. I let you think about it.
    There are also great convergence zones (subduction zones/mountain belts), that doesn’t make any trouble in plate tectonics.
    They do, because plate tectonics predicts that in these convergent boundaries, the lower lithosphere is the most mobile part (it is sinking) whereas every evidence show that the mobile part is the arc or the fold belt.


    Quote Originally Posted by The Geographer View Post
    No, if the was no load over the oceanic lithosphere, it would not sink. The facts, just the facts. The oldest Pacific/Atlantic/Indian Ocean lithosphere is certainly not sinking despite its age is about 170-180 Ma, even better for the eastern basin of the Mediterranean sea which oldest lithosphere is 280 My and is along Egypt.
    What do you mean by load? Another plate which overruns the subducted plate? Yes! Sedimentmaterial? No! It’s just a question of density not only weight… so you always need a plate.
    It is a question of isostatic equilibrium. When a piece of oceanic lithosphere is loaded with an overthrusting lithosphere, the oceanic lithosphere sinks until it reaches its point of isostatic equilibrium. Without the load of the overthrusting lithosphere the oceanic lithosphere will not sink as demonstrated by the fact that the 280 Ma-old mediterranean seafloor along Egypt does not sink.


    Quote Originally Posted by The Geographer View Post
    On both side of the Yarlung-Zang Bo suture? What are these sediments. I must look at what they are and where their are. Do you have references?
    No, this suture is interpreted as back-arc basin. Sutures of wide oceans doesn’t look like in books written (because the older oceanic lithosphere is in most cases subducted), so they are very hard to find (and like I wrote above they are in most times still not found today). Perhaps you also take a look at “Petrology and geochemistry of the Saga and Sangsang ophiolitic massifs, Yarlung Zangbo Suture Zone, Southern Tibet: Evidence for an arc–back-arc origin” (2009).
    I know this work. It is evidence that the Tibetan region was not different that the western mediterranean sea: axifugal back-arc basins, the most recent one overprinting the older one.
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    Whatever, you did'nt read this paper did you?

    Zorin. Geodynamics of the western part of the Mongolia-Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia. Tectonophysics (1999) vol. 306 (1) pp. 33-56
    Don't bother visiting my Earth Sciences forum, it died a death due to lack of love
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    Quote Originally Posted by billiards View Post
    Whatever, you did'nt read this paper did you?

    Zorin. Geodynamics of the western part of the Mongolia-Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia. Tectonophysics (1999) vol. 306 (1) pp. 33-56
    Oh, yes, I read it. In particular that part:
    "paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10°-15° away from each other (Fig. 5B). "


    Which is easily explained by the expanding earth theory. On a smaller Earth, a 10°-15° difference corresponds to a much shorter distance, the arc length being directly proportional to the radius. It follows that the two continental mass were not separated by a large gulf, and were close enough to allow the spread of Siberian flora to Mongolia. The remnants of active margins at the interface of Mongolia and Siberia simply testify for an important mantle flow paleoactivity, much like in todays alpine-himalayan belt system. So long for your " conclusive evidence in favour of plate tectonics, and firmly rules out the possibility of an expanding Earth".



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    Quote Originally Posted by florian View Post
    Attributing every region of fast velocity zone to a slab does not make any sense. Fast velocities can be related to difference in composition, in phase...
    Well let’s rather say on temperature and density (=phase+composition) so with the s and p waves reacting different on this both parameters we could distinguish both very good the bigger problem are the “masks” used for the regions (especially the crust) which the waves are passing before
    Maybe you know whats gonna be told to students before 10-20 years, the mantle is homogenouse they said, since we know such pics like above nobody says this, so now they had to declare why this can be, and the easiest way is to declare it by subduction, and so really every anomaly has to be something going up or going down or something cooled down.
    Quote Originally Posted by florian View Post
    The slab under Japan is well defined thanx to earthquakes, but if you believe that it refutes Earth Expansion, then it means that you don't understand overthrusting.
    No, but you always argue against subduction
    Quote Originally Posted by florian View Post
    Quote Originally Posted by The Geographer View Post
    This is not a simple local expansion comparable to something like gravity sliding. This a a new rift evolving into ridge, not different that the one developing in the Red Sea.
    It’s just another subducted MOR like the Japanese ocean.
    The Japanese ocean? Do you mean the sea of Japan? this is a marginal sea.
    Yes, I meant its going to be a sea like the sea of japan, but it’s in its very beginning.

    You don’t mind any motion of the pacific plate. Didn’t you realize that your own movie about the plate movement of the pacific declares how this fan can be where it is?
    […] This model predicts that the fan originates in the middle of the Pacific far away from Alaska.[…]
    Exactly that’s not true, take a close look at your vid
    There are also great convergence zones (subduction zones/mountain belts), that doesn’t make any trouble in plate tectonics.
    They do, because plate tectonics predicts that in these convergent boundaries, the lower lithosphere is the most mobile part (it is sinking) whereas every evidence show that the mobile part is the arc or the fold belt.
    Ok I understand your problem, but there are at least 3 models which can declare that there is extensional movement contrary to the subducted plate, the first is called slab break off, when this is happening, a little plume like upwelling is opening a Back-Arc basin and the second is called slab roll-back (I think I don’t have to declare you this, have I?). The third is called pull-apart basin perhaps just google for a picture, it’s pretty difficult to declare. These models are very important to declare also how there could be pathways for the magmas there are studies which say that there are fluids which had been risen in 80 years from the subducted slab to the surface, to declare that this fluids haven’t gone in the mantle you need pathways which are thought to be created by earthquakes.


    It is a question of isostatic equilibrium. When a piece of oceanic lithosphere is loaded with an overthrusting lithosphere, the oceanic lithosphere sinks until it reaches its point of isostatic equilibrium. Without the load of the overthrusting lithosphere the oceanic lithosphere will not sink as demonstrated by the fact that the 280 Ma-old mediterranean seafloor along Egypt does not sink.
    A Boat even has a higher density than the water around, it’s the same and it’s not sinking, there is just the first “touch” missing, and it’s going to sink. Once a slab has reached the zone where eclogite is being created there is no way back and it sinks.

    I know this work. It is evidence that the Tibetan region was not different that the western mediterranean sea: axifugal back-arc basins, the most recent one overprinting the older one.
    What is a axifugal back arc basin?
    Quote Originally Posted by florian View Post
    Oh, yes, I read it. In particular that part:
    "paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10°-15° away from each other (Fig. 5B). "

    Which is easily explained by the expanding earth theory. On a smaller Earth, a 10°-15° difference corresponds to a much shorter distance, the arc length being directly proportional to the radius. It follows that the two continental mass were not separated by a large gulf, and were close enough to allow the spread of Siberian flora to Mongolia. The remnants of active margins at the interface of Mongolia and Siberia simply testify for an important mantle flow paleoactivity, much like in todays alpine-himalayan belt system. So long for your " conclusive evidence in favour of plate tectonics, and firmly rules out the possibility of an expanding Earth".
    In spite of that this isn't very logic because if there had been really a distance of 10-15° in there position they shouldn't have had the same flora/fauna, and it also could be daclared by migratory birds and there also had been something called Gondwana and Pangea... so there had been a “landbridge” and there position to each other shouldn’t have changed if I had a right look at such pics of Pangea wrong...
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    Whether or not subduction occurs is not really interesting to me. The last 300 myears has not shown a significant amount (of subduction) as all the continents will fit on a globe 30 to 40 % smaller and not leave an appreciable space between them. There is an elephant in the room. If the continents are separated by oceans that are less than 300 million years old, where did the extra water come from? Was the earth shaped like a cigar with ice at the poles? Was there an extraterrestrial source? This time period coincides with the explosion of life on the earth and giant life forms at that. Does this mean a lower gravitational pull?

    Why are many of the plates separating and has this stopped in the present?
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    Quote Originally Posted by jetstove View Post
    The last 300 myears has not shown a significant amount (of subduction)
    thats just happening in your model, seismic pictures are showing us that there is subducted crust, with the metamorphic chains in japan you also can say that there had been subduction.

    as all the continents will fit on a globe 30 to 40 % smaller and not leave an appreciable space between them.
    a fact which is also simple declared by plate tectonics but what should there have been before 300 Ma? I don't see any evidence that the earth should have been smaller

    If the continents are separated by oceans that are less than 300 million years old, where did the extra water come from?
    Thats a question you have to answer, I say they had been already there since ~ 4.x Ga

    Why are many of the plates separating
    If you had read my post before this, maybe it would be a little bit clearer to you.
    Last edited by The Geographer; April 17th, 2012 at 05:05 PM.
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    Quote Originally Posted by The Geographer View Post
    Well let’s rather say on temperature and density (=phase+composition)...
    Stop you right there. Temperature and density are certainly not equal to phase and composition.

    Quote Originally Posted by The Geographer View Post
    so with the s and p waves reacting different on this both parameters we could distinguish both very good the bigger problem are the “masks” used for the regions (especially the crust) which the waves are passing before
    Yes that is another source of error.

    Quote Originally Posted by The Geographer View Post
    Maybe you know whats gonna be told to students before 10-20 years, the mantle is homogenouse they said, since we know such pics like above nobody says this, so now they had to declare why this can be, and the easiest way is to declare it by subduction, and so really every anomaly has to be something going up or going down or something cooled down.
    You just demonstrate how the interpretation of tomographies is biased by the prevailing theory. This is blatant circular reasoning. No good science.

    Quote Originally Posted by The Geographer View Post
    No, but you always argue against subduction
    I argue against the oceanic lithosphere as the driving force in a Benioff zone, not against the presence of a slab.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    The Japanese ocean? Do you mean the sea of Japan? this is a marginal sea.
    Yes, I meant its going to be a sea like the sea of japan, but it’s in its very beginning.
    I don't follow you. You wrote that the nascent ridge in the gulf of Califonia was a "subducted MOR like the Japanese ocean" (sic). but the Sea of Japan is not a subducted MOR, it is a marginal sea (a back-arc basin).

    Quote Originally Posted by The Geographer View Post
    You don’t mind any motion of the pacific plate. Didn’t you realize that your own movie about the plate movement of the pacific declares how this fan can be where it is?
    […] This model predicts that the fan originates in the middle of the Pacific far away from Alaska.[…]
    Exactly that’s not true, take a close look at your vid
    you're mistaken. I captured a frame of the animation at 38 Ma in middle of the time deposition. The position of the fan is represented by the thick line.



    It is far from its source (Alaska) with even a MOR separating it from its source.
    This is a clear refutation of the plate tectonic model.

    Quote Originally Posted by The Geographer View Post
    Ok I understand your problem, but there are at least 3 models which can declare that there is extensional movement contrary to the subducted plate, the first is called slab break off, when this is happening, a little plume like upwelling is opening a Back-Arc basin and the second is called slab roll-back (I think I don’t have to declare you this, have I?). The third is called pull-apart basin perhaps just google for a picture, it’s pretty difficult to declare. These models are very important to declare also how there could be pathways for the magmas there are studies which say that there are fluids which had been risen in 80 years from the subducted slab to the surface, to declare that this fluids haven’t gone in the mantle you need pathways which are thought to be created by earthquakes.
    I know all of that. The point is that the driving force is the mantle under the back-arc basin. The mantle induces the roll-back. I remind you the scheme that illustrates how mantle upwelling can drive a rollback and open a marginal sea:




    Quote Originally Posted by The Geographer View Post
    It is a question of isostatic equilibrium. When a piece of oceanic lithosphere is loaded with an overthrusting lithosphere, the oceanic lithosphere sinks until it reaches its point of isostatic equilibrium. Without the load of the overthrusting lithosphere the oceanic lithosphere will not sink as demonstrated by the fact that the 280 Ma-old mediterranean seafloor along Egypt does not sink.
    A Boat even has a higher density than the water around, it’s the same and it’s not sinking, it’s the same and it’s not sinking, there is just the first “touch” missing, and it’s going to sink.
    Actually not. Divide the mass of a boat by its volume and you will see that it has lower density than water. If it was not the case, it would sink. So your analogy fails.

    Quote Originally Posted by The Geographer View Post
    Once a slab has reached the zone where eclogite is being created there is no way back and it sinks.
    Eclogitization does only affect the crust (not the whole lithosphere) and it is partial anyway.

    I know this work. It is evidence that the Tibetan region was not different that the western mediterranean sea: axifugal back-arc basins, the most recent one overprinting the older one.
    What is a axifugal back arc basin?
    The motion of the arc is axifugal relatively to the axis of the back-arc basin. It means that the arc is moving outward, away from the back-arc. This is particularly evident in the Mediterranean Sea or in the Banda back-arc:


    Quote Originally Posted by The Geographer View Post
    In spite of that this isn't very logic because if there had been really a distance of 10-15° in there position they shouldn't have had the same flora/fauna,
    ?? That's the point.

    Quote Originally Posted by The Geographer View Post
    and it also could be daclared by migratory birds
    Birds during the permian????

    Quote Originally Posted by The Geographer View Post
    and there also had been something called Gondwana and Pangea... so there had been a “landbridge” and there position to each other shouldn’t have changed if I had a right look at such pics of Pangea wrong...
    I think you should read the paper.
    Last edited by florian; April 18th, 2012 at 03:43 PM.
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    Quote Originally Posted by The Geographer View Post
    Stop you right there. Temperature and density are certainly not equal to phase and composition.
    What’s really measured? The density and Temperature! And out of this and experiments you get phase and composition.

    You just demonstrate how the interpretation of tomographies is biased by the prevailing theory. This is blatant circular reasoning. No good science.
    In spite of you’re also argueing like that, I just wanted to say that we have an explanation for those negative anomalies what about you?

    I argue against the oceanic lithosphere as the driving force in a Benioff zone, not against the presence of a slab.
    That depends on which Benioff zone you argue I wouldn’t call it the driving force at the south American coast but in front of Japan it is! I even don’t know why you are argueing at all about this, we know for sure that there is something called eclogite which has a very high density, there is just a start impulse necessary.

    Quote Originally Posted by florian View Post
    but the Sea of Japan is not a subducted MOR, it is a marginal sea (a back-arc basin).
    In your video about the plate motions, you should also have seen that (in the model of plate tectonics) there had been in its very beginning a former MOR which had been subducted, just after it had been subducted there was an upwelling, so I can declare why there is an upwelling.

    you're mistaken. I captured a frame of the animation at 38 Ma in middle of the time deposition. The position of the fan is represented by the dash circle.



    It is far from its source (Alaska) with even a MOR separating it from its source.
    This is a clear refutation of the plate tectonic model.
    … OK this picture is made in the eyes of plate tectonics, do you agree? So this what is red is today 38 Ma do you also agree? In your picture http://nachon.free.fr/iso5/Iso5Npacific.png parts of the fan are lying on the oceanic crust which is dated between 45-50 Ma at their youngest parts, calculating this minus 38 I’m at 7-12 Ma that would be the boarder between the deepest red and orange so your circle is much too far west; on its other (oldest) side it’s about 80 Ma so minus 38 Ma = 42 Ma so you should be never in the yellow color. And its not that far away from… Oregon (?) I think this was also mentioned as possible source of the material.

    I know all of that. The point is that the driving force is the mantle under the back-arc basin. The mantle induces the roll-back. I remind you the scheme that illustrates how mantle upwelling can drive a rollback and open a marginal sea:
    Ok, so we are just argueing in different directions… but why should there be an upwelling? I guess because of the subducted crust?

    A Boat even has a higher density than the water around, it’s the same and it’s not sinking, it’s the same and it’s not sinking, there is just the first “touch” missing, and it’s going to sink.
    Actually not. Divide the mass of a boat by its volume and you will see that it has lower density than water. If it was not the case, it would sink. So your analogy fails.
    Ok, then forget the boat and take the gerridae

    Eclogitization does only affect the crust (not the whole lithosphere) and it is partial anyway.
    Ok, just the crust but the whole crust

    What is a axifugal back arc basin?
    The motion of the arc is axifugal relatively to the axis of the back-arc basin. It means that the arc is moving outward, away from the back-arc. This is particularly evident in the Mediterranean Sea or in the Banda back-arc:
    ok

    Quote Originally Posted by The Geographer View Post
    In spite of that this isn't very logic because if there had been really a distance of 10-15° in there position they shouldn't have had the same flora/fauna,
    ?? That's the point.
    The point is that the flora and fauna shouldn’t have existed for the same point of time in both places like you proposed it.
    So maybe first the fauna changed it’s position maybe cause of a climate change and with it the flora

    Quote Originally Posted by The Geographer View Post
    and it also could be daclared by migratory birds
    Birds during the permian????
    Let me correct it “something like migratory birds”, I don’t know which animals had been living there but there are a couple of animals which are doing journeys

    I think you should read the paper.
    No access :-/
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    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    Stop you right there. Temperature and density are certainly not equal to phase and composition.
    What’s really measured? The density and Temperature! And out of this and experiments you get phase and composition.
    What is really measured? Seismic waves arrival time! Not density and temperature! The density/temperature is just one interpretation made after a sequence of various assumption, like that the mantle is homogenous (PREM)...

    Quote Originally Posted by The Geographer View Post
    You just demonstrate how the interpretation of tomographies is biased by the prevailing theory. This is blatant circular reasoning. No good science.
    In spite of you’re also argueing like that, I just wanted to say that we have an explanation for those negative anomalies what about you?
    This is a very long shot hypothesis that could be either right or completely wrong. That is a limit of models.

    Quote Originally Posted by The Geographer View Post
    I argue against the oceanic lithosphere as the driving force in a Benioff zone, not against the presence of a slab.
    That depends on which Benioff zone you argue I wouldn’t call it the driving force at the south American coast but in front of Japan it is! I even don’t know why you are argueing at all about this, we know for sure that there is something called eclogite which has a very high density, there is just a start impulse necessary.
    The Japanese arc (and the arc only, especially the fore-arc, not the back-arc) flowed toward and over the Pacific seafloor. The coseismic displacements are crystal-clear. So the driving force is clearly the outward spreading of mantle in the back-arc. Eclogite does not form before 45 km depth or so. If the oceanic lithosphere were not overloaded by the mantle wedge, it would not reach such a depth.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    but the Sea of Japan is not a subducted MOR, it is a marginal sea (a back-arc basin).
    In your video about the plate motions, you should also have seen that (in the model of plate tectonics) there had been in its very beginning a former MOR which had been subducted, just after it had been subducted there was an upwelling, so I can declare why there is an upwelling.
    Do you really persist in claiming that the back-arc of Japanese arc is a subducted MOR? Really? and what about the Marian back-arc? Is it also a subducted MOR? Philippine sea as well?

    Quote Originally Posted by The Geographer View Post
    … OK this picture is made in the eyes of plate tectonics, do you agree? So this what is red is today 38 Ma do you also agree? In your picture http://nachon.free.fr/iso5/Iso5Npacific.png parts of the fan are lying on the oceanic crust which is dated between 45-50 Ma at their youngest parts, calculating this minus 38 I’m at 7-12 Ma that would be the boarder between the deepest red and orange so your circle is much too far west; on its other (oldest) side it’s about 80 Ma so minus 38 Ma = 42 Ma so you should be never in the yellow color. And its not that far away from… Oregon (?) I think this was also mentioned as possible source of the material.
    No, the source is in the gulf of Alaska, not Oregon. There is a late ravenian cooler period identified in a borehole that is only recognized onshore of the gulf of Alaska.
    Besides the fan deposition migrated eastward (eastern channels are the most recent), so that the eastern part of the fan was deposited around 32 My. I updated the figure to reproduce the shape of the fan. There is no doubt that the fan is far from the gulf of Alaska. Plus there is that hypothetic ridge midway, a high topography that the sediments would have to cross.

    Quote Originally Posted by The Geographer View Post
    Ok, so we are just argueing in different directions… but why should there be an upwelling? I guess because of the subducted crust?
    No, you invert cause and consequence. The upwelling is the primary event explaining the existence of a slab. In an expanding earth, upwelling are dominant in the upper mantle because the segregation is ongoing. Lighter material is constantly evacuated toward the surface.


    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    In spite of that this isn't very logic because if there had been really a distance of 10-15° in there position they shouldn't have had the same flora/fauna,
    ?? That's the point.
    The point is that the flora and fauna shouldn’t have existed for the same point of time in both places like you proposed it.
    So maybe first the fauna changed it’s position maybe cause of a climate change and with it the flora
    I did not proposed it, it is reported by Nie et al (1990) Geol. Soc. Mem. Am. 12, 12397-12409. The Flora could spread from siberia to mongolia because both places were connected. Remember Wegener's argument for Pangea?

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    and it also could be daclared by migratory birds
    Birds during the permian????
    Let me correct it “something like migratory birds”, I don’t know which animals had been living there but there are a couple of animals which are doing journeys
    As far as I know, there were no flying vertebrates during the permian.

    Quote Originally Posted by The Geographer View Post
    I think you should read the paper.
    No access :-/
    Want it?
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    Quote Originally Posted by florian View Post
    Quote Originally Posted by billiards View Post
    Whatever, you did'nt read this paper did you?

    Zorin. Geodynamics of the western part of the Mongolia-Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia. Tectonophysics (1999) vol. 306 (1) pp. 33-56
    Oh, yes, I read it. In particular that part:
    "paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10°-15° away from each other (Fig. 5B). "


    Which is easily explained by the expanding earth theory. On a smaller Earth, a 10°-15° difference corresponds to a much shorter distance, the arc length being directly proportional to the radius. It follows that the two continental mass were not separated by a large gulf, and were close enough to allow the spread of Siberian flora to Mongolia. The remnants of active margins at the interface of Mongolia and Siberia simply testify for an important mantle flow paleoactivity, much like in todays alpine-himalayan belt system. So long for your " conclusive evidence in favour of plate tectonics, and firmly rules out the possibility of an expanding Earth".



    So you happily gloss over the detailed synthesis of many lines of evidence and cherry pick a sentence. Too bad you weren't paying close attention, otherwise you would have seen that in the very next sentence following the section you quoted, the text continues ...

    [quote]Paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10o–15o away from each other (Fig. 5B). This controversy between the paleomagnetic evidence for separation and geological evidence for collision can be settled as follows.[/quote]

    The resolution comes by the fact that the two landmasses were brought together by the rotation of Mongolia, hence the West side (then the north) was genuinely quite far away with an ocean in the middle, and the southern tip (then the east) was close enough for life to cross. This is much more satisfactory than the "easy" explanation of expanding earth, because if anything on an expanding earth things get further apart not closer together! Furthermore there is a wealth of evidence in the calc-alkaline sequence of volcanics which tells the story of the rotation in fantastic detail. If you read the paper an array of detailed geological field observations from the thickness of the crust to the occurence of gold seams are neatly tied together within the framework of plate tectonics. The seismic tomography results which I took from another paper are quite simply the cherry on top.




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    Quote Originally Posted by billiards View Post
    So you happily gloss over the detailed synthesis of many lines of evidence and cherry pick a sentence. Too bad you weren't paying close attention, otherwise you would have seen that in the very next sentence following the section you quoted, the text continues ...
    Paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10o–15o away from each other (Fig. 5B). This controversy between the paleomagnetic evidence for separation and geological evidence for collision can be settled as follows.
    The resolution comes by the fact that the two landmasses were brought together by the rotation of Mongolia, hence the West side (then the north) was genuinely quite far away with an ocean in the middle, and the southern tip (then the east) was close enough for life to cross. This is much more satisfactory than the "easy" explanation of expanding earth, because if anything on an expanding earth things get further apart not closer together!
    Wrong. The rotation is not used as an argument to explain the discrepancy during the permian. The rotation happened later during the triassic as shown in figure 5C-D.
    This is the full paragraph:

    "The Mongolia–Okhotsk ocean as an enormousgulf of the Paleopacific formed in the earliest Permian when Mongolia at its western part had joined Siberia in the region of Khangay, as evidenced by the presence of Permian continental molasse and voluminous calc-alkaline granitoids (Zonenshain etal., 1990). Paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Permian thus indicating the presence of a bridge be-tween the two continents (Nie et al., 1990). On theother hand, paleomagnetic data for the Late Permian(Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10°–15° away from each other (Fig. 5B). This controversy between the paleomagnetic evidence for separationand geological evidence for collision can be settled as follows. First, paleomagnetic reconstructions forSiberia and Mongolia are of low accuracy. So, the position of the virtual magnetic pole for low-magnetic late Paleozoic rock sequences was determined at an accuracy of 9–11° at a 95% confidence level(Zhao et al., 1990; Kuzmin and Kravchinsky, 1996). Second, the continental crust may have shortened after collision by at least 500–600 km by its deformation and thrusting beneath Siberia (Nie et al.,1990; Zorin et al., 1998a). "

    So they say, that after all, the paleomagnetic data were not accurate enough, and they evoke that thrusting would have shorten the crust (whereas thrusting is induced by a rising mass spreading nearby, so that the surface area does not decrease). They use a plate tectonic hypothetic concept of surface area shortening in support of... plate tectonics. Typical circular reasoning.

    Quote Originally Posted by billiards View Post
    Furthermore there is a wealth of evidence in the calc-alkaline sequence of volcanics which tells the story of the rotation in fantastic detail. If you read the paper an array of detailed geological field observations from the thickness of the crust to the occurence of gold seams are neatly tied together within the framework of plate tectonics.
    Arc volcanism and craton rotation is not plate tectonics specific.

    Quote Originally Posted by billiards View Post
    The seismic tomography results which I took from another paper are quite simply the cherry on top.
    The cherry on the top of circular reasoning, for sure.
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    Quote Originally Posted by florian View Post
    What is really measured? Seismic waves arrival time! Not density and temperature! The density/temperature is just one interpretation made after a sequence of various assumption, like that the mantle is homogenous (PREM)...
    Ok, but with s and p waves reacting different on density and temperature this is not a such “deep” interpretation like phase+composition (which require also labrotatory investigations), in spite of the density depends on those parameters.

    The Japanese arc (and the arc only, especially the fore-arc, not the back-arc) flowed toward and over the Pacific seafloor. The coseismic displacements are crystal-clear. So the driving force is clearly the outward spreading of mantle in the back-arc. Eclogite does not form before 45 km depth or so. If the oceanic lithosphere were not overloaded by the mantle wedge, it would not reach such a depth.
    You forget the steps between, there is also something called Greenschist, Blueschist and Jadeit is already stable at 7 kbar that should be about 20 km, normal eclogite is usually formed at something around 45 km. Also the cooled down lithosphere has already a slightly higher density than the upper mantle

    Quote Originally Posted by florian View Post
    Do you really persist in claiming that the back-arc of Japanese arc is a subducted MOR? Really?
    It resulted out of a subducted MOR. Yes, that’s the most common opinion atm.
    Quote Originally Posted by florian View Post
    and what about the Marian back-arc? Is it also a subducted MOR? Philippine sea as well?
    As I already stated there is not just one model to declare a Back-arc-basin… slab roll back, slab break off… perhaps even more.
    No, the source is in the gulf of Alaska, not Oregon. There is a late ravenian cooler period identified in a borehole that is only recognized onshore of the gulf of Alaska.
    Besides the fan deposition migrated eastward (eastern channels are the most recent), so that the eastern part of the fan was deposited around 32 My. I updated the figure to reproduce the shape of the fan. There is no doubt that the fan is far from the gulf of Alaska. Plus there is that hypothetic ridge midway, a high topography that the sediments would have to cross.
    Not if they are swimming above it on an ice shield. I have big problems with your argumentation with your borehole, what exactly is there recognized? And a missing of something today is no absolute evidence that there hadn’t been something.

    No, you invert cause and consequence. The upwelling is the primary event explaining the existence of a slab. In an expanding earth, upwelling are dominant in the upper mantle because the segregation is ongoing. Lighter material is constantly evacuated toward the surface.
    I understand, but I don’t agree (still arguing the otherway around)

    I did not proposed it, it is reported by Nie et al (1990) Geol. Soc. Mem. Am. 12, 12397-12409. The Flora could spread from siberia to mongolia because both places were connected. Remember Wegener's argument for Pangea?
    1990, maybe today we know it better, but as I already mentioned stratigraphy is in my eyes boring, so I don’t know it better

    Let me correct it “something like migratory birds”, I don’t know which animals had been living there but there are a couple of animals which are doing journeys
    As far as I know, there were no flying vertebrates during the permian.
    You just need animals making journeys, and maybe even not that, if the climate changed not too fast.

    Quote Originally Posted by The Geographer View Post
    I think you should read the paper.
    No access :-/
    Want it?[/QUOTE]
    Yes, I would appreciate this.

    To our discussion about sutures I found a quite new article about the border between India and Eurasia Welcome to AGU Online Services
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    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    What is really measured? Seismic waves arrival time! Not density and temperature! The density/temperature is just one interpretation made after a sequence of various assumption, like that the mantle is homogenous (PREM)...
    Ok, but with s and p waves reacting different on density and temperature this is not a such “deep” interpretation like phase+composition (which require also labrotatory investigations), in spite of the density depends on those parameters.
    But you agree that if the mantle is not rigorously homogenous, the density/temperature interpretation becomes unsupported, right?
    Quote Originally Posted by The Geographer View Post
    The Japanese arc (and the arc only, especially the fore-arc, not the back-arc) flowed toward and over the Pacific seafloor. The coseismic displacements are crystal-clear. So the driving force is clearly the outward spreading of mantle in the back-arc. Eclogite does not form before 45 km depth or so. If the oceanic lithosphere were not overloaded by the mantle wedge, it would not reach such a depth.
    You forget the steps between, there is also something called Greenschist, Blueschist and Jadeit is already stable at 7 kbar that should be about 20 km, normal eclogite is usually formed at something around 45 km. Also the cooled down lithosphere has already a slightly higher density than the upper mantle
    The slightly higher density of the cooled down and metamorphized (at depth) oceanic lithosphere prevent it to "slide out" of the mantle when it is buried under the overrunning mantle.

    BTW, sometimes, picture do ring a bell. The following one is a view of the Mariana arc (Google Earth).



    It is like waves of treacle spreading over a table.
    By analogy, you believe that the treacle is not spreading, but that the table is sliding under the treacle. Does it make any sense?

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Do you really persist in claiming that the back-arc of Japanese arc is a subducted MOR? Really?
    It resulted out of a subducted MOR. Yes, that’s the most common opinion atm.
    The hypothetic ridge subduction was supposed to happen circa 55 Ma. But the sea of Japan started to open in the early miocene (23 Ma). What did happened during 30 Ma?

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    and what about the Mariana back-arc? Is it also a subducted MOR? Philippine sea as well?
    As I already stated there is not just one model to declare a Back-arc-basin… slab roll back, slab break off… perhaps even more.
    Or the mantle upwelling under the backarc is responsible for the slab rollback and slab break off...

    Quote Originally Posted by The Geographer View Post
    No, the source is in the gulf of Alaska, not Oregon. There is a late ravenian cooler period identified in a borehole that is only recognized onshore of the gulf of Alaska.
    Besides the fan deposition migrated eastward (eastern channels are the most recent), so that the eastern part of the fan was deposited around 32 My. I updated the figure to reproduce the shape of the fan. There is no doubt that the fan is far from the gulf of Alaska. Plus there is that hypothetic ridge midway, a high topography that the sediments would have to cross.
    Not if they are swimming above it on an ice shield.
    At least 280,000 km3 of sediments on a ice shield!? You were not serious.

    Quote Originally Posted by The Geographer View Post
    I have big problems with your argumentation with your borehole, what exactly is there recognized? And a missing of something today is no absolute evidence that there hadn’t been something.
    A cooler period is absent in the biostratigraphy south of the gulf of Alaska. It won't reappear magically if it is not seen today.

    This is the full paragraph from Stevenson et al 1983:

    "Sparse pollen and spore assemblages recovered from the turbidite interval in Hole 183 are generally dominated by broad-leafed genera with subordinate conifers. One anomalous sample is dominated by conifers, with minor amounts of broad-leafed pollens (Wolfe, 1973; Evitt, 1973). Samples both above and below the conifer-rich sample show the common distribution. Biostratigraphic data from exposed Paleogene rocks adjacent to the Gulf of Alaska have been interpreted by Wolfe (1977) to imply that climatic cooling, which favored the development of a large warm-temperate forest environment suitable for conifers, occurred during the late Ravenian (middle late Eocene). This cooler interval is bordered on both sides by warmer climates during which semitropical broadleaved evergreen forest predominated. The cooler middle late Eocene period represented in the Gulf of Alaska onshore deposits can be correlated with the anomalous conifer interval recovered from Hole 183, and the warmer flora recovered from the core above and below the conifer interval fit well with the coeval onshore flora. These correlations imply a similar, or possibly slightly cooler, climate for the source of the sediments at Site 183. Little paleogeographic information can be deduced from the subtropical flora recovered at Site 183, because equivalent floras are known throughout the Gulf of Alaska, British Columbia, and the northwestern United States during the middle Ravenian (= late middle Eocene through early late Eocene) and Kummerian (= late late Eocene through early Oligocene) (Wolfe, 1973, 1977; Rouse, 1977). In contrast, the late Ravenian cooler period, recorded both in onshore deposits and in the cores from Hole 183, is not recognized farther south than the Gulf of Alaska. Taken together with nannofossil evidence, this suggests to us that both the fan and its source terrane lay no farther south in the late Eocene than the latitude of the Gulf of Alaska. "

    Quote Originally Posted by The Geographer View Post
    I did not proposed it, it is reported by Nie et al (1990) Geol. Soc. Mem. Am. 12, 12397-12409. The Flora could spread from siberia to mongolia because both places were connected. Remember Wegener's argument for Pangea?
    1990, maybe today we know it better, but as I already mentioned stratigraphy is in my eyes boring, so I don’t know it better
    How can you find stratigraphy boring when it is at the core of geology? Surely, that could explain in part why you got cheated by plate tectonics.

    Quote Originally Posted by The Geographer View Post
    As far as I know, there were no flying vertebrates during the permian.
    You just need animals making journeys, and maybe even not that, if the climate changed not too fast.
    Animals making journey over an ocean without flying? not more serious than the ice shield.

    Quote Originally Posted by The Geographer View Post
    Want it?
    Yes, I would appreciate this.
    In your mailbox.

    Quote Originally Posted by The Geographer View Post
    To our discussion about sutures I found a quite new article about the border between India and Eurasia Welcome to AGU Online Services Where does India end and Eurasia begin?
    Thank you for the paper. So they push the border further north. Interestingly, as that gondwana fragment is at odd with current reconstructions, they even explain that the closures do not necessitate subduction and collision but that inversion of stress field would give the same result. This is exactly my view. Cross-cutting or coliding mantle flows do exactly that. They open back-arc and close back-arc.
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    Quote Originally Posted by florian View Post
    But you agree that if the mantle is not rigorously homogenous, the density/temperature interpretation becomes unsupported, right?
    I was taught that phase and composition just effect the arrival time by effecting the density, so I would say no.

    It is like waves of treacle spreading over a table.
    By analogy, you believe that the treacle is not spreading, but that the table is sliding under the treacle. Does it make any sense?
    You missed that those "waves" are no waves, they are nothing existing out of any tectonic at all, they are young magmatic provinces, resulting out of the rigid subducted plate, which opens pathways for magmas out of the upper mantle. There is even a special name for those magmatic provinces, but I don't remember at the moment.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Do you really persist in claiming that the back-arc of Japanese arc is a subducted MOR? Really?
    It resulted out of a subducted MOR. Yes, that’s the most common opinion atm.
    The hypothetic ridge subduction was supposed to happen circa 55 Ma. But the sea of Japan started to open in the early miocene (23 Ma). What did happened during 30 Ma?
    Crustal thinning doesn't happen in one day and the oldest oceanic crust in google earth is dated with 40 Ma, and thats even very in the middle of the japanese sea so maybe even much older crust is still lying burried under sediments being not dated yet.

    Quote Originally Posted by The Geographer View Post
    Not if they are swimming above it on an ice shield.
    At least 280,000 km3 of sediments on a ice shield!? You were not serious.
    Over 10 My! This wouldn't have been a single event. How this should have worked is illustrated for example here on heinrich events http://www.geo.tu-freiberg.de/oberse...nne_zechel.pdf in picture 10 (= abb. 10) and picture 11 (= abb. 11) you will always get problems declaring those great distances of this fan only with liquid water. I have big problems with your argumentation with papers which are from the 80'ies referring even to papers from the 70'ies. The people didn't know what we know today for sure.

    How can you find stratigraphy boring when it is at the core of geology? Surely, that could explain in part why you got cheated by plate tectonics.
    Well I'm like my name is saying it correctly geographer, the landscape and how it evolved was always my main topic, interesting points for me are things which aren't known so good, things were you can really find something totally new, thats really hard when you argue about stratiphy. And to be more precious it's the living things in stratigraphy which are boring, things like when did the atmosphere got enough oxide to build something like BIF's are totally different.

    Quote Originally Posted by The Geographer View Post
    As far as I know, there were no flying vertebrates during the permian.
    You just need animals making journeys, and maybe even not that, if the climate changed not too fast.
    Animals making journey over an ocean without flying? not more serious than the ice shield.

    Want it?
    Yes, I would appreciate this.
    In your mailbox.
    thx

    So they push the border further north. Interestingly, as that gondwana fragment is at odd with current reconstructions, they even explain that the closures do not necessitate subduction and collision but that inversion of stress field would give the same result.
    They don't necessitate large amounts of subduction thats a difference! And there is still a large crustal shortage required... isn't this controversal to a expanding earth?

    Animals making journey over an ocean without flying? not more serious than the ice shield.
    I thought there should have been landbridges
    Last edited by The Geographer; April 28th, 2012 at 04:51 PM.
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    Quote Originally Posted by florian View Post
    The slightly higher density of the cooled down and metamorphized (at depth) oceanic lithosphere prevent it to "slide out" of the mantle when it is buried under the overrunning mantle.

    BTW, sometimes, picture do ring a bell. The following one is a view of the Mariana arc (Google Earth).


    It is like waves of treacle spreading over a table.
    By analogy, you believe that the treacle is not spreading, but that the table is sliding under the treacle. Does it make any sense?
    But I wouldn't contradict you saying the mantle is convecting faster than the plates are moving
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    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    But you agree that if the mantle is not rigorously homogenous, the density/temperature interpretation becomes unsupported, right?
    I was taught that phase and composition just effect the arrival time by effecting the density, so I would say no.
    Do you disagree with Anderson when he says that low-velocity is not equal to hot-buoyant-raising and high-velocity is not equal to dense-cold-sinking? He cites the root of cratons as examples of high-velocity zone that have low density and are buoyant.

    Quote Originally Posted by The Geographer View Post
    It is like waves of treacle spreading over a table.
    By analogy, you believe that the treacle is not spreading, but that the table is sliding under the treacle. Does it make any sense?
    You missed that those "waves" are no waves, they are nothing existing out of any tectonic at all, they are young magmatic provinces, resulting out of the rigid subducted plate, which opens pathways for magmas out of the upper mantle. There is even a special name for those magmatic provinces, but I don't remember at the moment.
    That is actually incorrect. There are waves of mantle exhumation and surface spreading as testified by the sequential eastward opening of the West Philippines basin, Parace Vela basin and Mariana trough.

    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by florian View Post
    Do you really persist in claiming that the back-arc of Japanese arc is a subducted MOR? Really?
    It resulted out of a subducted MOR. Yes, that’s the most common opinion atm.
    The hypothetic ridge subduction was supposed to happen circa 55 Ma. But the sea of Japan started to open in the early miocene (23 Ma). What did happened during 30 Ma?
    Crustal thinning doesn't happen in one day and the oldest oceanic crust in google earth is dated with 40 Ma, and thats even very in the middle of the japanese sea so maybe even much older crust is still lying burried under sediments being not dated yet.
    Are you sure that this 40 Ma is not an artifact from the map? There are not unusual. Every papers I read on the subject report an opening of the Sea of Japan circa 23 Ma.


    Quote Originally Posted by The Geographer View Post
    Quote Originally Posted by The Geographer View Post
    Not if they are swimming above it on an ice shield.
    At least 280,000 km3 of sediments on a ice shield!? You were not serious.
    Over 10 My! This wouldn't have been a single event. How this should have worked is illustrated for example here on heinrich events http://www.geo.tu-freiberg.de/oberse...nne_zechel.pdf in picture 10 (= abb. 10) and picture 11 (= abb. 11) you will always get problems declaring those great distances of this fan only with liquid water. I have big problems with your argumentation with papers which are from the 80'ies referring even to papers from the 70'ies. The people didn't know what we know today for sure.
    I suppose that you understand that this kind of sediment transport is very different than fluvial transport with branched channels and so on? Do you admit that your hypothesis is completely unsupported?

    Besides your assertion that 80's paper are good for the trash is frightening. They contains a wealth of perfectly valid data. You might question some interpretations of the data but not the data themselves.

    Quote Originally Posted by The Geographer View Post
    So they push the border further north. Interestingly, as that gondwana fragment is at odd with current reconstructions, they even explain that the closures do not necessitate subduction and collision but that inversion of stress field would give the same result.
    They don't necessitate large amounts of subduction thats a difference! And there is still a large crustal shortage required... isn't this controversal to a expanding earth?
    The fact that large amount of oceanic lithosphere recycling is not necessary to explain the geology is a key point made by the expanding earth.
    And I remind you that the snow plowing effect of spreading mantle flow explains crustal shortage very well. Even better, it also explains the arcuate shape of the fold belts.
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    Do you disagree with Anderson when he says that low-velocity is not equal to hot-buoyant-raising and high-velocity is not equal to dense-cold-sinking? He cites the root of cratons as examples of high-velocity zone that have low density and are buoyant.


    saying "
    low-velocity is not equal to hot-buoyant-raising and high-velocity is not equal to dense-cold-sinking" is not the same like saying p and s waves are reacting different on temperature and density and he is also saying about the roots of cratons that they are very cool and that parts can break off and sink, so they aren't even buoyant. So if one parameter is very extreme (T low or density high) the both wave arrival times will take longer but in a different way.

    That is actually incorrect. There are waves of mantle exhumation and surface spreading as testified by the sequential eastward opening of the West Philippines basin, Parace Vela basin and Mariana trough.


    In your picture you seemed to argue about waves in front of a subduction zone now you are arguing about a back-arc-basin (like it is shown us here https://wiki.carleton.edu/display/te...pine+Sea+Plate) which is behind a subduction zone, so two completly different things. By the way the magmatic provinces in front of subduction zones are called Petit Spots. And wasn't this formerly your argument against an active sinking subducted plate, so your argumentation doesn't fit twice.

    Are you sure that this 40 Ma is not an artifact from the map? There are not unusual. Every papers I read on the subject report an opening of the Sea of Japan circa 23 Ma.


    You're missing the important point. The important point is that the 23 Ma are not representing the point of time when there was a change from a compressional to an extensional movement. I guess the "Sea" just tells us from which point of time there had been water in this structure, but that has not so much to do with it's geomorphological structure or situation.

    I suppose that you understand that this kind of sediment transport is very different than fluvial transport with branched channels and so on? Do you admit that your hypothesis is completely unsupported?


    Yes, you are right, but your former point that the fan had been lying in the eyes of plate tectonics in the mid of the pacific is wrong. And if I'm following your argumentation there should be similar fans in the mid of the pacific, so where are they? And the zodiac fan had not neccesarily to stay in this position, it's even unlikely.

    Besides your assertion that 80's paper are good for the trash is frightening. They contains a wealth of perfectly valid data. You might question some interpretations of the data but not the data themselves.
    cause they just quote data fitting to their wrong assumptions
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    Quote Originally Posted by The Geographer View Post

    saying "
    low-velocity is not equal to hot-buoyant-raising and high-velocity is not equal to dense-cold-sinking" is not the same like saying p and s waves are reacting different on temperature and density

    And "saying p and s waves are reacting different on temperature and density" is not the same like saying there is cold sinking mantle in that region.

    Quote Originally Posted by The Geographer View Post
    and he is also saying about the roots of cratons that they are very cool and that parts can break off and sink, so they aren't even buoyant.
    I missed that part. Where does he say that? What is the density for the root of a craton, 2.8? Why would it sink?


    Quote Originally Posted by The Geographer View Post
    So if one parameter is very extreme (T low or density high) the both wave arrival times will take longer but in a different way.
    I guess you meant shorter.
    Back to basics. Seismic wave velocities depend on density and elasticity. How does density and elasticity vary with composition (lithology, mineralogy and chemistry), phase (like melt content) and temperature?

    Quote Originally Posted by The Geographer View Post
    That is actually incorrect. There are waves of mantle exhumation and surface spreading as testified by the sequential eastward opening of the West Philippines basin, Parace Vela basin and Mariana trough.


    In your picture you seemed to argue about waves in front of a subduction zone now you are arguing about a back-arc-basin (like it is shown us here https://wiki.carleton.edu/display/te...pine+Sea+Plate) which is behind a subduction zone, so two completly different things. By the way the magmatic provinces in front of subduction zones are called Petit Spots. And wasn't this formerly your argument against an active sinking subducted plate, so your argumentation doesn't fit twice.

    Petit spots volcanism is related to lithosphere flexure upstream of the path of the mobile arc. I was not arguing about that but about the arc system (this includes its back arc). The fact is that the arcs system formed in waves, with a new arc system burgeoning from the existing arc. For example the Kyushu arc and the West Mariana arc used to be part of a unique arc that got separated in two by the opening of the Parace Vela Basin. It is very well established. The same kind of event took place during the opening of the Mariana Trough.

    Quote Originally Posted by The Geographer View Post

    You're missing the important point. The important point is that the 23 Ma are not representing the point of time when there was a change from a compressional to an extensional movement. I guess the "Sea" just tells us from which point of time there had been water in this structure, but that has not so much to do with it's geomorphological structure or situation.

    23 Ma is the onset of the extension.

    Quote Originally Posted by The Geographer View Post
    Yes, you are right, but your former point that the fan had been lying in the eyes of plate tectonics in the mid of the pacific is wrong.
    While it is not exactly in the middle of the pacific, I remind you that the fan lies beyond an hypothetic ridge in the plate tectonics model, a bathymetric barrier that sediments can't cross, and far away from Alaska.


    Quote Originally Posted by The Geographer View Post
    And if I'm following your argumentation there should be similar fans in the mid of the pacific, so where are they?
    To have similar fans you need similar large drainage systems. Where do you see another one?
    Actually, the Meiji sediment deposit in the pacific northwest is also at odd with Pacific subduction as expected from plate tectonics models.

    Quote Originally Posted by The Geographer View Post
    And the zodiac fan had not neccesarily to stay in this position, it's even unlikely.
    Actually, the fan moved slightly away from Alaska as new seafloor was formed along the active margin, but the fan got rapidly catch up by the mobile aleutian arc.

    Quote Originally Posted by The Geographer View Post
    Besides your assertion that 80's paper are good for the trash is frightening. They contain a wealth of perfectly valid data. You might question some interpretations of the data but not the data themselves.
    cause they just quote data fitting to their wrong assumptions

    80's paper do not systematically use wrong assumptions! And you can figure it out by reading the paper and more recent papers on the subject if they exist.
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    And "saying p and s waves are reacting different on temperature and density" is not the same like saying there is cold sinking mantle in that region.
    Ok, you jumped with the theme, you are talking about subducted slabs? Well if there is a subduction zone over a anomaly in the mantle than this is a quite logical interpretation and it’s very funny that Anderson is also arguing on things like that.

    I missed that part. Where does he say that?
    Oh he didn’t mention this in the article? :-D take a look here (second author ANDERSON!) http://anquetil.colorado.edu/geophys..._1998_EPSL.pdf Is this really so surprising for you for you that Anderson didn’t mention this on this site? I hope not. I’m sorry if I sounded sarcastic but it seemed to me that you got fooled by him.

    What is the density for the root of a craton, 2.8? Why would it sink?
    Because it’s cooled down? No idea what exact density, but geophysical pictures are showing us some downward movement here, maybe just because of an abnormal warm mantle here. Isotopic evidences from the canary islands are very similar to isotopic signatures in the atlas mountains in Morocco.

    I guess you meant shorter.
    Right, shorter.

    Seismic wave velocities depend on density and elasticity. How does density and elasticity vary with composition (lithology, mineralogy and chemistry), phase (like melt content) and temperature?
    The problem for me is the elasticity, the only thing I can say it has obviously more effect on the s-waves.

    23 Ma is the onset of the extension.
    I think this is nonsense, can you cite a point where exactly that is mentioned?! I don’t think so. The 23 Ma are in my eyes obviously related to the sea of Japan and to nothing more. If in google earth there would be a 30 Ma border right on the very edges of the Japanese sea I would say ok, you might be right, but even the 40 Ma border is quite in the mid of the Japanese sea. The east african rift is 20 Ma old and there is still no ocean.

    The fact is that the arcs system formed in waves, with a new arc system burgeoning from the existing arc. For example the Kyushu arc and the West Mariana arc used to be part of a unique arc that got separated in two by the opening of the Parace Vela Basin. It is very well established. The same kind of event took place during the opening of the Mariana Trough.
    …do you want to hear a plate tectonic argumentation about that?

    While it is not exactly in the middle of the pacific, I remind you that the fan lies beyond an hypothetic ridge in the plate tectonics model, a bathymetric barrier that sediments can't cross
    The fan is still lying to far west in your picture. And you’re forgetting the very little grainsize (size fraction: 0.149-0.25 mm) and the ocean currents which would have blown it away from the MOR.

    and far away from Alaska.
    We already know that also Oregon is a possibility maybe Oregon wasn’t very icy to this time, but the water could have only run through it.

    To have similar fans you need similar large drainage systems. Where do you see another one?
    Actually, the Meiji sediment deposit in the pacific northwest is also at odd with Pacific subduction as expected from plate tectonics models.
    It’s quite good declared by ocean currents today and even not an example for a fan in the middle of an ocean.
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    Quote Originally Posted by The Geographer View Post
    And "saying p and s waves are reacting different on temperature and density" is not the same like saying there is cold sinking mantle in that region.
    Ok, you jumped with the theme, you are talking about subducted slabs? Well if there is a subduction zone over a anomaly in the mantle than this is a quite logical interpretation and it’s very funny that Anderson is also arguing on things like that.
    I'm not talking about the anomalies that correlate well with hypocenters (slabs) but about the anomalies in the upper or lower mantle, often diffuse, that are systematically intepreted as old slabs, or sinking material in general. This is an overinterpretation of the data.
    Quote Originally Posted by The Geographer View Post
    Oh he didn’t mention this in the article? :-D take a look here (second author ANDERSON!) http://anquetil.colorado.edu/geophys..._1998_EPSL.pdf Is this really so surprising for you for you that Anderson didn’t mention this on this site? I hope not. I’m sorry if I sounded sarcastic but it seemed to me that you got fooled by him.
    Hmm, that paper is about edge-driven flows. It does not say that the root of craton is so dense that it sinks in the mantle. Are you sure it is the correct reference?

    Quote Originally Posted by The Geographer View Post
    What is the density for the root of a craton, 2.8? Why would it sink?
    Because it’s cooled down? No idea what exact density, but geophysical pictures are showing us some downward movement here, maybe just because of an abnormal warm mantle here. Isotopic evidences from the canary islands are very similar to isotopic signatures in the atlas mountains in Morocco.
    Cooling down a material make shift its density from 2.8 to more than 3.3? Ir emind you that the PREM model aready gives a mantle density about 3.38 at 25 km depth.

    Quote Originally Posted by The Geographer View Post
    I guess you meant shorter.
    Right, shorter.
    Seismic wave velocities depend on density and elasticity. How does density and elasticity vary with composition (lithology, mineralogy and chemistry), phase (like melt content) and temperature?
    The problem for me is the elasticity, the only thing I can say it has obviously more effect on the s-waves.
    What factor has the bigger impact on elasticty? Composition, phase or temperature? It seems that the later as the lesser effect.

    Quote Originally Posted by The Geographer View Post
    23 Ma is the onset of the extension.
    I think this is nonsense, can you cite a point where exactly that is mentioned?! I don’t think so. The 23 Ma are in my eyes obviously related to the sea of Japan and to nothing more. If in google earth there would be a 30 Ma border right on the very edges of the Japanese sea I would say ok, you might be right, but even the 40 Ma border is quite in the mid of the Japanese sea. The east african rift is 20 Ma old and there is still no ocean.
    OK, I had to dig in the literature and I found that you are correct regarding the early rifting stage (middle eocene). But I found no reference to your hypothesis that ridge subduction is at the origin of the Sea of Japan. Instead, the Sea of Japan is a pull-apart basin that is thought to result from the India-Asia collision.

    "The aforementioned pull-apart system evolved during Indo-Eurasian collision, which produced a transform boundary between the Eurasian continent andplates of the Pacific Ocean. This boundary developed inplace of the Cretaceous–Paleogene convergent boundary (Filatova, 2004; Jolivet et al., 1990). The transform boundary is associated with a broad system of closelyspaced submeridional dextral strike-slip faults. Thetranspressional regime resulted in Eocene continentalrifting and the development of pull-apart basins in theregions of the Russian Southern Far East–China–Japanand Sea of Okhotsk." (N. I. Filatova Petrology, 2008, Vol. 16, No. 5, pp. 448–467.)

    As a matter of fact I've never read nowhere in any texbook or paper that ridge subduction could trigger back-arc opening. Where did you get the idea? Is it yours?

    Quote Originally Posted by The Geographer View Post
    The fact is that the arcs system formed in waves, with a new arc system burgeoning from the existing arc. For example the Kyushu arc and the West Mariana arc used to be part of a unique arc that got separated in two by the opening of the Parace Vela Basin. It is very well established. The same kind of event took place during the opening of the Mariana Trough.
    …do you want to hear a plate tectonic argumentation about that?
    I imagine That is probably something like slab break-off (which is not seen for the Mariana slab anyway), but go on with your argumentation…

    Quote Originally Posted by The Geographer View Post
    While it is not exactly in the middle of the pacific, I remind you that the fan lies beyond an hypothetic ridge in the plate tectonics model, a bathymetric barrier that sediments can't cross
    The fan is still lying to far west in your picture. And you’re forgetting the very little grainsize (size fraction: 0.149-0.25 mm) and the ocean currents which would have blown it away from the MOR.
    I put the fan at the right position using the isochrons from Stevenson et al 1983.
    Except that you forget the full channel system that are at odd with sediments blown away from a ridge. By contrats, the channel system suggest that the north-east tip of the fan was close to the continent, as predicted by the EE model.

    Quote Originally Posted by The Geographer View Post
    and far away from Alaska.
    We already know that also Oregon is a possibility maybe Oregon wasn’t very icy to this time, but the water could have only run through it.
    No, Oregon is not a possibility, remember the cooling event not seen souther than the gulf of Alaska.

    Quote Originally Posted by The Geographer View Post
    To have similar fans you need similar large drainage systems. Where do you see another one?
    Actually, the Meiji sediment deposit in the pacific northwest is also at odd with Pacific subduction as expected from plate tectonics models.
    It’s quite good declared by ocean currents today and even not an example for a fan in the middle of an ocean.
    It should have been since the pacific lithosphere is thought to have been subducted under Kamtchatka by more than 3000 km (9cm/y) since the Meiji drift started to form 35 Ma ago. But the Meiji drift is "only" 1000 km long so that the older sediments should have been subducted for a long time. So how is that possible? Simple, the Pacific lithosphere is not moving. But the mantle upflows along the east asian margin are slowly outpouring on the Pacific seafloor.
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    Quote Originally Posted by florian View Post
    Quote Originally Posted by billiards View Post
    So you happily gloss over the detailed synthesis of many lines of evidence and cherry pick a sentence. Too bad you weren't paying close attention, otherwise you would have seen that in the very next sentence following the section you quoted, the text continues ...
    Paleobiogeographic data attest that the Siberian flora spread into Mongolia since the Per- mian thus indicating the presence of a bridge be- tween the two continents (Nie et al., 1990). On the other hand, paleomagnetic data for the Late Permian (Zhao et al., 1990; Enkin et al., 1992) place Siberia and the western margin of Mongolia at least 10o–15o away from each other (Fig. 5B). This controversy between the paleomagnetic evidence for separation and geological evidence for collision can be settled as follows.
    The resolution comes by the fact that the two landmasses were brought together by the rotation of Mongolia, hence the West side (then the north) was genuinely quite far away with an ocean in the middle, and the southern tip (then the east) was close enough for life to cross. This is much more satisfactory than the "easy" explanation of expanding earth, because if anything on an expanding earth things get further apart not closer together!
    Wrong. The rotation is not used as an argument to explain the discrepancy during the permian. The rotation happened later during the triassic as shown in figure 5C-D.


    Um, well think about it the rotation happened later, sure, but the fact that Mongolia and Siberia were close together at the hinge of the rotation before the rotation happened fully explains how animals could hop from one island to the other whilst the palaeo-mag shows the bulk of the landmasses were far apart.


    Quote Originally Posted by billiards View Post
    The seismic tomography results which I took from another paper are quite simply the cherry on top.
    The cherry on the top of circular reasoning, for sure.
    [/quote]
    No, the new evidence is independent, I don't see how it is circular. As your favourite Earth Scientist, Don Anderson described it, we are using the "geocentric" method (in a very specific sense, that does not have anything to do with the pre-Copernicans), as although the "ab initio" method might be better philosophically, it is intractable to use the ab initio approach to do most of Earth science. i.e. the geocentric approach is basically 'observe the Earth and then explain it' usually with the help of some paradigm. This is subtly different from circular reasoning.
    Don't bother visiting my Earth Sciences forum, it died a death due to lack of love
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    Quote Originally Posted by billiards View Post

    Um, well think about it the rotation happened later, sure, but the fact that Mongolia and Siberia were close together at the hinge of the rotation before the rotation happened fully explains how animals could hop from one island to the other whilst the palaeo-mag shows the bulk of the landmasses were far apart.

    They were separated by 10-15 degrees at the hinge!

    Quote Originally Posted by billiards View Post
    No, the new evidence is independent, I don't see how it is circular. As your favourite Earth Scientist, Don Anderson described it, we are using the "geocentric" method (in a very specific sense, that does not have anything to do with the pre-Copernicans), as although the "ab initio" method might be better philosophically, it is intractable to use the ab initio approach to do most of Earth science. i.e. the geocentric approach is basically 'observe the Earth and then explain it' usually with the help of some paradigm. This is subtly different from circular reasoning.
    The interpretation of tomographies is done using plate tectonic "glasses". We are far from the multiple working hypothesis method which should be the method of choice.
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    I'm not talking about the anomalies that correlate well with hypocenters (slabs) but about the anomalies in the upper or lower mantle, often diffuse, that are systematically intepreted as old slabs, or sinking material in general. This is an overinterpretation of the data.
    Well, if we are talking about the lower mantle anomalies, there are always discussions like are they hot and of normal density or are they of normal temperatures and of lower density, but that’s in my eyes just the problem of the quality of the measured data which can be fixed in a view years. Otherwise about anomalies in the upper mantle I don’t know any example where you can say here is a subductionzone very unlikely.
    Hmm, that paper is about edge-driven flows. It does not say that the root of craton is so dense that it sinks in the mantle. Are you sure it is the correct reference?
    Formerly the paper was evidence just for the point that Anderson also says that the roots of cratons are very cold. There are several papers of interest on this topic, it’s summed up in Schmin>Flow of Canary mantle plume material through a subcontinental lithospheric corridor beneath Africa to the Mediterranean
    Cooling down a material make shift its density from 2.8 to more than 3.3? Ir emind you that the PREM model aready gives a mantle density about 3.38 at 25 km depth.
    And I remind you that there is a mantle anomaly (=Hot Spot/Plume) its rather a Delamination process.
    What factor has the bigger impact on elasticty? Composition, phase or temperature? It seems that the later as the lesser effect.
    Definitely phase…
    OK, I had to dig in the literature and I found that you are correct regarding the early rifting stage (middle eocene). But I found no reference to your hypothesis that ridge subduction is at the origin of the Sea of Japan. Instead, the Sea of Japan is a pull-apart basin that is thought to result from the India-Asia collision.

    "The aforementioned pull-apart system evolved during Indo-Eurasian collision, which produced a transform boundary between the Eurasian continent andplates of the Pacific Ocean. This boundary developed inplace of the Cretaceous–Paleogene convergent boundary (Filatova, 2004; Jolivet et al., 1990). The transform boundary is associated with a broad system of closelyspaced submeridional dextral strike-slip faults. Thetranspressional regime resulted in Eocene continentalrifting and the development of pull-apart basins in theregions of the Russian Southern Far East–China–Japanand Sea of Okhotsk." (N. I. Filatova Petrology, 2008, Vol. 16, No. 5, pp. 448–467.)

    As a matter of fact I've never read nowhere in any texbook or paper that ridge subduction could trigger back-arc opening. Where did you get the idea? Is it yours?
    No, a post-doc who is actually making his habilitation told me, he also promised me to search for the paper, but months ago, I guess he didn’t find it. By the way in the eyes of plate tectonics it’s quite logical that with a subducted MOR an extension in the Back-Arc starts, or just gets reinforced.
    I imagine That is probably something like slab break-off (which is not seen for the Mariana slab anyway), but go on with your argumentation…
    Well without any paper or something like this I would make another suggestion. With earth being a globe and the slabs being one part for the first subducted kilometers it wasn’t possible to subduct it in the way of the form of the coast line so there was a new subduction zone created, so it would be just a matter of structure.
    I put the fan at the right position using the isochrons from Stevenson et al 1983.
    Except that you forget the full channel system that are at odd with sediments blown away from a ridge. By contrats, the channel system suggest that the north-east tip of the fan was close to the continent, as predicted by the EE model.
    Those channels can also be created by ocean currents.
    No, Oregon is not a possibility, remember the cooling event not seen souther than the gulf of Alaska.
    You don’t need a cooling if the water just ran through this area.
    It should have been since the pacific lithosphere is thought to have been subducted under Kamtchatka by more than 3000 km (9cm/y) since the Meiji drift started to form 35 Ma ago. But the Meiji drift is "only" 1000 km long so that the older sediments should have been subducted for a long time. So how is that possible? Simple, the Pacific lithosphere is not moving. But the mantle upflows along the east asian margin are slowly outpouring on the Pacific seafloor.
    Well this isn’t really material which can’t be transported by ocean currents (take a look at it’s grainsize!), which are working much faster than the 9cm/y, if you’re calculating 3000km/35Ma you get about 100 meter per year (or about 27 cm a day) that sounds very realistic in my eyes.
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    Quote Originally Posted by florian View Post
    I'm not talking about the anomalies that correlate well with hypocenters (slabs) but about the anomalies in the upper or lower mantle, often diffuse, that are systematically intepreted as old slabs, or sinking material in general. This is an overinterpretation of the data.
    There is more evidence to support the interpretation than purely the tomography. For example the anomalies extend downward from known subduction zones (linking the tomography to surface observations). Earthquakes happen where these anomalies exits. Seismic energy scatters from these anomalies, evidence of a SHARP change in material. The mantle is anisotropic around these anomalies, and the anisotropy shows a fabric which fits the inferred flow pattern from the slab interpretation. The geoid is anomalous over these anomalies. The dynamic topography is anomalous over these anomalies. The transition is thicker in these regions.

    To be clear, not everything that is blue in a tomographic image has to be cold downweliing material, but there is a lot of supporting evidence to support the interpretation that a lot of this blue stuff really is cold downwelling stuff.

    Quote Originally Posted by The Geographer
    Well, if we are talking about the lower mantle anomalies, there are always discussions like are they hot and of normal density or are they of normal temperatures and of lower density, but that’s in my eyes just the problem of the quality of the measured data which can be fixed in a view years. Otherwise about anomalies in the upper mantle I don’t know any example where you can say here is a subductionzone very unlikely.
    The lower mantle anomalies you are talking about (I think) are something different, these are the "large low shear velocity provinces" (LLSVPs). These anomalies are here to stay, they won't simply "go away" with more data/ better techniques.
    Don't bother visiting my Earth Sciences forum, it died a death due to lack of love
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