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Thread: Questions on Fossils that I've Always Wondered About

  1. #1 Questions on Fossils that I've Always Wondered About 
    Forum Radioactive Isotope zinjanthropos's Avatar
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    Do scientists ever discover bones that are undergoing the fossilization process? Perhaps a bone that's only partially mineralized. Are there bones found in this intermediate transitory phase or is fossilization rapid once it gets started? Is it either the finding of fossilized bones or skeletal remains with no in-between stage?

    In the same vein, how old is the youngest fossil ever found?


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  3. #2  
    Forum Ph.D.
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    the youngest fossils are about 10,000 years old, this is the minimum time that it takes to form a fossil.

    Your first question is a bit tricky to phrase but in short yes you can find fossils half mineralised & such have been found. You just need to distinguish when its bone/tissue & when its fossil!


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    Forum Radioactive Isotope zinjanthropos's Avatar
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    Quote Originally Posted by Robbie
    the youngest fossils are about 10,000 years old, this is the minimum time that it takes to form a fossil.

    Your first question is a bit tricky to phrase but in short yes you can find fossils half mineralised & such have been found. You just need to distinguish when its bone/tissue & when its fossil!
    Thanks for the response.

    I've just returned from a visit with my brother in Alberta Canada. While there I had a chance to visit the *Royal Tyrell Museum of Paleontology in a place called Drumheller. It is in the heart of the Alberta Badlands which have produced some of the most amazing dinosaur fossils ever found. I still can't believe the size of one of the T-rex's on display there.

    There was one fossil in particular that intrigued me the most. It was an ammonite about 3' across with a most spectacular array of colors on its polished surfaced. I can't figure out how this fossil became so adorned, because when you walk the Badlands you see nothing that would indicate these colors are evident. Could that be the actual colors of the ancient marine creature?

    *There are numerous trails through the Badlands just outside the museum's doors. I found several pieces of petrified wood and according to a nearby geologist I also picked up some fossilized bone fragments. Quite an exciting place and worth the trip.
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  5. #4  
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by zinjanthropos
    There was one fossil in particular that intrigued me the most. It was an ammonite about 3' across with a most spectacular array of colors on its polished surfaced.
    under unusual circumstances the original aragonite shell cover can remain intact (which is what i assume the shiny cover is), although in most instances it gets converted to calcite during fossilisation
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  6. #5 What makes a fossil ? 
    Forum Sophomore CShark's Avatar
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    What minerals are replaced in bone, to become stone ? Do the same compounds work the same way when other tissues become fossilized ?
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  7. #6  
    Time Lord
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    Quote Originally Posted by zinjanthropos
    Quite an exciting place and worth the trip.
    Yeah in a lot of ways Mars seems dull and shallow in comparison.

    I have family whose property borders the Badlands - it just ends where the prairie drops off. Grandma used to climb down to collect shells and such before paleontologists moved on the area. How anyone could grow up there and be a Creationist is beyond me. Maybe they all thought it was the Flood.


    Here's the "gem stone" ammolite, AKA partially fossilized ammonite shell. Gaudy!


    "the Bearpaw Formation of southern Alberta, Canada - has revealed two species of Placenticeras ammonite, whose organic shell mineral aragonite had not been converted to stable calcite (both forms of calcium carbonate), due to unique geological conditions. Rather, stacked layers of aragonite plates (lamellae) of varying thicknesses, together with a middle layer of randomly interspersed crystals of organic conchiolin, and several trace minerals, have the capability of refracting light into brilliant, vibrant colors." ...more...

    EDIT: It just occurred to me that these colours are visible, like mother-of-pearl, on the shell's inside. So, no, the living ammonite wouldn't show such markings.
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  8. #7 Re: What makes a fossil ? 
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by CShark
    What minerals are replaced in bone, to become stone ? Do the same compounds work the same way when other tissues become fossilized ?
    in bone that would be calcium phosphate, although any organic object that doesn't rot away is a candidate for fossilisation (e.g. permineralised tree trunks)
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  9. #8 Re: What makes a fossil ? 
    Forum Sophomore CShark's Avatar
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    Quote Originally Posted by marnixR
    Quote Originally Posted by CShark
    What minerals are replaced in bone, to become stone ? Do the same compounds work the same way when other tissues become fossilized ?
    in bone that would be calcium phosphate, although any organic object that doesn't rot away is a candidate for fossilisation (e.g. permineralised tree trunks)
    You sure, my friend ? Calcium phosphate just doesn't seem to fit. I always thought that various minerals just replaced the tissue, basically, like pouring plaster into a mold: you are left with plaster. What I don't know is what that plaster is made of in the case of a fossil. You certainly could be right....anyone else comment on this ?
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  10. #9 Re: What makes a fossil ? 
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by CShark
    You sure, my friend ? Calcium phosphate just doesn't seem to fit. I always thought that various minerals just replaced the tissue, basically, like pouring plaster into a mold: you are left with plaster. What I don't know is what that plaster is made of in the case of a fossil. You certainly could be right....anyone else comment on this ?
    i think there may be a misunderstanding here : it's the calcium phosphate that gets replaced by whatever percolates through the sediment that holds the bones
    organic remains like collagen usually decay very quickly but traces can remain for some time under unusual preservation conditions (often involving anoxic conditions in water or very dry conditions on land)
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  11. #10 Re: What makes a fossil ? 
    Forum Sophomore CShark's Avatar
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    Quote Originally Posted by marnixR
    Quote Originally Posted by CShark
    You sure, my friend ? Calcium phosphate just doesn't seem to fit. I always thought that various minerals just replaced the tissue, basically, like pouring plaster into a mold: you are left with plaster. What I don't know is what that plaster is made of in the case of a fossil. You certainly could be right....anyone else comment on this ?
    i think there may be a misunderstanding here : it's the calcium phosphate that gets replaced by whatever percolates through the sediment that holds the bones
    organic remains like collagen usually decay very quickly but traces can remain for some time under unusual preservation conditions (often involving anoxic conditions in water or very dry conditions on land)
    Thanks for clarifying that. NOW It makes sense!
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