I would like to know how an animal becomes a fossil under many feet of earth and stays intact.
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I would like to know how an animal becomes a fossil under many feet of earth and stays intact.
Try a search engine first. Read a few websites. If you have any more specific questions wheen you're done, then come and ask them.
This should help:
http://en.wikipedia.org/wiki/Fossilisation
There's also a list of references at the end for more detailed reading.
Ok, I should have been more specific. Other than a flood, how could an animal stay intact to fossilize? Other than being frozen suddenly.
Typically, they don't. Part of the reason why complete fossils are quite rare is that dead animals are fed upon by others. The remains are distributed. They may still fossilise at that point of course. This is expected and so it's no surprise that most large animal fossils are partial.Originally Posted by mastmec
So, to answer your question, the remains merely need to be partially sheltered and remote enough to be inaccessible to wildlife. This is rare, but over a few hundred million years, it'll happen plenty.
that's why most fossils are found in marine, lake or river sediments - they stand a better chance of being covered by more sedimentsts before they completely disintegrate, which is what usually happens to a corpse that remains uncovered on e.g. the savannah
In addition to the good answers above see here:
http://www.enchantedlearning.com/sub...Fossilhow.html
Unless of course fossils were put in the earth by the Great Pink Unicorn to confuse humans.
So all those fish fossils are from the fish dying and going to the bottom of the water and being covered by sediment? Then over a long period of time turn to a fossil? I've allways seen fish float and get washed to the shore. What would cause it to go to the floor of the water and get covered up?
This seems unlikely, but it is what I find on all the web sites and in my kids science books. I only see that this could happen from a disaster scenerio, not the slow process of this getting covered and then the slow process of fossilizing. Logically these things would happen quickly.
Fish have a buoyancy bladder which, if it were to burst, would make the fish sink.Originally Posted by mastmec
http://www.lookd.com/fish/gasbladder.html
Of couse all the dead fish you see float. If they sunk and got buried, how would you ever know?
Out of curiosity, what kind of disaster do you suppose would make a floaty fish in to a sinky one?
I could see a great turbulance in the water causing the ground to churn and fish getting cought in it getting buried, like the fossil of the fish giving birth and those that have just eaten with whole fish in thier belly. Fossils of closed clams also shows evidence of this.
and where would that great turbulence come from ?
There are a few types of gas bladders. Some are connected to the gut so the fish can gulp air to refill or burp to sink. I presume that a fish with this type of bladder might burp some of its gas when the muscles release when they die, making it sink a bit, where the increased pressure makes it burp some more, etc. Other fish can have their bladders burst when they ascend to quickly (like when they die for instance) and then they sink.
http://en.wikipedia.org/wiki/Gas_bladder
Please, don't say a big flood might do this.I could see a great turbulance in the water causing the ground to churn and fish getting cought in it getting buried, like the fossil of the fish giving birth and those that have just eaten with whole fish in thier belly. Fossils of closed clams also shows evidence of this.![]()
Earthquake, flood, volcano, ect.
sedimentation can happen in a variety of ways, only some of which are turbulent and/or catastrophic - the Burgess shale is thought to represent the burial of organisms by the collapse of an unstable submarine cliff
however, other environments, such as the Solnhofen limestone could only have occurred in very still waters
That is a cool artical and there is an instance of something tring to escape, which means somthing happened quickly to cause it to be covered up. All of these creatures could have been buried at the same time.
Yes, "is thought to represent the burial of organisms by the collapse of an unstable submarine cliff".Originally Posted by mastmec
Cool article as you say.
I was refering to the Solnhofen Limestone fossils.
Oh, sorry.![]()
An excerpt from marnixR's link:
"The sheets of limestone are so regular that we can only conclude that they were deposited in a calm environment. The deposits were evidently laid down under a stable body of water that had some connection to the Tethys Sea. Sponges and corals grew on rises in this sea, forming lagoons. In fact, remnants of a coral reef can be found in the area to the south of Solnhofen. The region must have been near land, however, due to the discovery of insects such as wonderfully-preserved dragonflies. Assuming that Jurassic coral reefs grew in modes similar to those of today, the surface of the reefs would have been only 10 meters or so under water. The maximum depth has been estimated by some to have been 60 meters (200 feet).
These isolated lagoons would have been quite stagnant due to little exchange of water with the sea. Anoxic conditions would have been ideal for preventing destruction of organisms that found their way into the lagoons. Some evidently survived for short periods. One of the most famous examples of this are the horseshoe crab "death spirals' that exist in which a spiral trackway has been preserved with the defunct arthropod in the center, presumably preserving its last efforts at survival. The theory most often proposed for the toxicity of the waters has been that of hypersalinity, the excessive concentration of salt. If the area were hot and dry, with little runoff from the land to the north, conditions would have been ideal for promoting excessive evaporation of water with concomitant increase in the salinity in the lagoons. The dense brine would collect in the bottom of the pools, excluding most life, as sensitivity to even minute changes in density has been seen in many marine organisms. Once an organism had been washed into the lagoon by the action of a storm, it would quickly succumb to the toxic conditions that existed within. The hypersaline, anoxic floor was ideal for the preservation of the body, often even leaving evidence of soft tissues."
The organism trying to escape was probably dying from the toxic environment it was washed into. Also, the smoothness and regularity of the rock indicates a slow formation in calm waters.
Indeed, a big flood would be more likely to fossilise any fish that had washed ashore.Originally Posted by KALSTER
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Originally Posted by free radical
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Actually a global flood probably would not be able to do this.
I'd like to add that the chondrichthyes (often also called 'fish') do not have swim bladders and have a tendency to sink if they do not stay constantly in motion. Ergo, upon death (however it may be caused) we would expect sharks, rays etc to sink, not rise.
on the other hand it is also true that corpses float because of gas build-up due to decomposition (mainly of the intestines) - once the skin is ruptured, however, the corpse would then sink
Aside from being impossible in itself due to the lack of sufficient water...Originally Posted by free radical
early fish had lungs instead of swim bladders. :wink:Originally Posted by mastmec
Anyway. If nothing would sink the oceans, lakes and streams would be covered with dead animals.
Imagine the stink.
This answer was derived from applying logic.
Only because the earth has mountainous terrain, at present. :wink:Originally Posted by TheBiologista
Fish may be trapped under ice. A dead floater will melt itself a pocket in the underside of ice, where perhaps if ice is forming - as in winter - the body may be preserved. Alternately, live fish in shallows are crowded down and trapped beneath a winter growth of ice. In this case they perish very slowly, with increasingly saline water and subzero temperature. From there, the frozen fish may be transported by tidal or geologic action. Spring floods could easily cover such salted fish with sediment.
Swedes call it gravlax "grave salmon" and it's a delicacy.
You all keep coming up with ways to sink to the bottom and get slowly covered up, where would all of the other life in the ocean, lake, pond be while the corpse just floats or sinks, whatever. But the likelyhood that a fish would not be eaten is about 0% since everything in the water is food for something else. There would have to be a catastraphy for it to be covered and fossilize.
There are over 6,000,000,000 people on the planet now.
If 99.99% of them did not fossilize, you would still arrive at 600,000 human fossils.
So, close to 0% chance still gives you plenty of fossils.
Most land animal fossils occur in areas near seas or seasonal flooding etc.
Wherever there are water currents or seasons there are ways fish become buried deep, suddenly. One storm at low water - where I am - can totally rearrange the undersea landscape. Also as I tried to suggest, a freezing environment will tend to pickle fish. Happens naturally every year.Originally Posted by mastmec
But you are right about catastrophes too. Earthquakes liquefy the ocean floor so that things sink down into it. If you're getting earthquakes every few years the bones could really pile up.
Which is the reason why complete fish fossils are so very very rare. They're not penny a dozen like the inedible parts of certain shelly things you know.Originally Posted by mastmec
And are those ways so implausible that they'd never happen? Given the sheer number of individual life forms that have existed, we only need this to happen at a very very low rate indeed to get fossils.Originally Posted by mastmec
About 0%? How close to it? Because if it's 0.00001% and there have been billions of fish then we're still talking about a whole load of fossils.Originally Posted by mastmec
Not at all, it merely needs to be covered sufficiently to hide or otherwise protect the remains from the elements and from other life. You could do that with a few millimeters of sediment in a secluded patch of sea floor.Originally Posted by mastmec
Lets assume you're right though. Answer me this then. Can you point to a process in nature that occurs today that causes the sort of rapid sedimentation and fossilisation required by flood geology? It needs to be fast, common and reproducible in order to explain the vast amount of layering we see in the fossil record if the Flood timeline is correct. We're talking dozens of meters of sedimentation and sedimentary rock formation from that in just a few thousand years.
+ it's a rare fossil indeed that becomes fully fossilised and petrified in a time span of the order of 10,000 years
...proving that fossilisation is a lie.![]()
You have rather stated an either/or. Hard to see how a creationist would be convinced by an ultimatum.
How is this an ultimatum? I'm afraid I don't see your point.Originally Posted by free radical
if a fossil cannot form in under ten thousand years then a creationist must either accept an old earth or deny fossils.
incredulity is not an argument.You all keep coming up with ways to sink to the bottom and get slowly covered up, where would all of the other life in the ocean, lake, pond be while the corpse just floats or sinks, whatever. But the likelyhood that a fish would not be eaten is about 0% since everything in the water is food for something else. There would have to be a catastraphy for it to be covered and fossilize.
it is, but it's a false one - nothing has ever stopped existing just because someone didn't believe in itOriginally Posted by spuriousmonkey
So has anyone ever found some fossilized remains?
Maybe the scientists made it all up.
Marnix.
I believe in you. Are the scientists photoshopping their pictures?!?!
I once found a fossilized coral on a beach. I was 10 though, so radioisotope dating was a non-runner.Originally Posted by spuriousmonkey
My grandmother grew up on a farm bordering Dinosaur Provincial Park. She'd climb down to collect shells and marvel at the big bones. Yet this cattle country is the heartland of Canada's Christian fundamentalists - she does believe God placed the triceratops' skulls and such in biblical times.
Fossilization can happen very quickly and has to or everything will just rot away.Originally Posted by free radical
And something else that does not float about the ground layering over many years, is there are fossilized trees standing upright and upside down within these many of layers that is said to show a time scale of millions of years.
Very quickly is a relative term, and a link to a fossilized tree existing through multiple geological strata would be appreciated.
I don't have a link to hand but such "polystrate fossils" do exist. Thing is, if you bury the roots of a tree, the top can still keep growing. Bury the trunk, it keeps growing...Originally Posted by free radical
Example please. Just one will do. Preferably one that can't be explained away by some post-fossilisation geological process.Originally Posted by mastmec
You do not seem to be suggesting that we do not understand fossilisation. Mastmec does.Originally Posted by Pong
In Australia by Katherine Hill Bay, there is a fossilized tree about 15' high extending through many layers, including 2 seperate layers of coal.
Can you provide a link to the primary paper or to an article citing it?Originally Posted by mastmec
The details are important, after all if the two coal layers have roughly the same age then all this represents is a case of rapid sedimentation (from a flood or pyroclastic surge or something like that). This would bury the tree in numerous strata in a short time but we'd be able to identify that by radioisotope dating of the strata.
Polystrate fossils are pretty rare, but like I alluded to before, they are always explicable by conventional geology and can't be taken as evidence of a global flood since we'd expect to see them everywhere if that were real.
fast burial is key. I've seen a cow buried, probably alive or immediately after death, in flood plain deposits. I saw several cow skeletons, later that trip, that were completely exposed- their bone had been greatly damaged after just a few months or less. This can really impact the quality of preservation in a bone, depending on the setting.
You resurrected a 6 year old thread to post this nonsense? Shame on you.
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