fossilization processes

I would like to see a good discussion of fossilization processes.Are all, or almost all, fossils considered (by mainstream, evolution-believing paleontologists) to be the result of mini-catastrophes? Or, do most paleontologists believe that fossils are the result of animals dying in their environment and being slowly covered up?I've read a few non-creationists' books on the subject (mostly geared for young people or high-school-aged children, though). These usually indicate that a creature dies in it's environment and is then slowly covered up over time -- lots of time. Over billions of years, of course, we wind up with layers and layers of fossils.Is this the opinion of actual paleontologists?I, of course, believe the Flood provides the explanation. However, I do not wish my thread to be plagued with questions about whether or not the Flood is possible. Instead, I would like for attention to be focussed on the process of fossilization itself.I actually don't expect the discussion to prove YEC assertions, as OEEs (old-earth evolutionists), even if the evidence was conclusive that EVERY fossil was of catastrophic origin, could argue countless mini-catastrophes have occurred over billions of years...or whatever.What I did want to see is whether people at this board tend to think fossilization is better explained by catastrophic events or by slow, normal processes...and their reasons for believing as they do.I would especially like to hear from the geologists like roxrkool, edge, JonF, etc. and -- if there are any at this board -- actual paleontologists.But everybody of all backgrounds would be welcome to throw in their 2 cents, too...in accordance with the EVC rules, of course...because I am also curious to see what non-geologists believe about the subject.--Jason(AbE: suggested forum is Geology and the Great Flood)This message has been edited by TheLiteralist, 07-26-2005 12:19 AM

Thread moved here from the Proposed New Topics forum.

The science here is called taphonomy. Google that and search here and you will find a lot.Generally, I think the "mini-catastrophes" is correct. Even bones don't last long in the open so it requires something special to preserve something long enough to fossilize.

I have a suspicion that most non-geologists and non-paleontologists believe in the died-and-were-slowly-covered-up idea.Thanks for the official name of the science. I'll google it.How ya been, Ned?--Jason

I don't know anything about taphonomy. I guess I have only a few uninformed comments. First, fossilization is thought to be relatively rare, though some environments can be more favorable to fossilization than others. For example, upland regions, which are areas of net erosion, are rarely preserved in the fossil record. That is why our knowledge of ancient land creatures is limited primarily to those that lived in low-lying coastal regions that were areas of net deposition.Second, no reasonable person would expect burial to be gradual. Exposure to the elements and to scavaging would cause the dead creature to completely disappear (though sheer size can be helpful in preserving the skeleton long enough to be buried, as is the case with large dinosaurs). That's another reason why fossilization is considered a rare event.Third, it can often be the case, though I don't know the percentages, that fossils contain no trace of the original bone. Over time seepage gradually dissolves the bone and leaves behind only inorganic material.--Percy

In some environments it can be. From A Whale of a Tale:

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Furthermore, a partially buried, articulated whale skeleton slowly being covered by sedimentation in the deep ocean off the coast of California was observed by oceanographers diving in submersibles. It is an excellent modern analogue of how this particular whale fossil was created without the need of a Noachian Flood (Allison et al. 1990; Smith et al. 1989).

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Allison, P. A., Smith, C. R., Kukert, H., Deming, J. W., and Bennett, B. A., 1990, Deep-water taphonomy of vertebrate carcasses: a whale skeleton in the bathyal Santa Catalina Basin. Paleobiology. vol. 17, pp. 78-89.

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Smith, C. R., Kukert, H., Wheatcroft, R. A., Jumars, P. A., and Deming, J. W., 1989. Vent fauna on whale remains. Nature, vol. 341, pp. 27-28. (Set. 7, 1989).

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Hmmm. A partially buried whale skeleton in deep ocean being slowly buried by sediments. Perhaps, but I have my doubts. Even if true, it's just an interesting subcase where the whale carcass has fallen out of range of the type of scavaging (both large and microbial) to which it would be vulnerable in more shallow waters.But the significant problem is that in most sea water environments the skeleton should gradually dissolve. For example, there are no skeletons aboard the Titanic. Perhaps there's something special about this region of the ocean that allows skeletal remains to persist for long periods. Regardless, if the sedimentation rate in this part of the ocean is faster than the skeleton can dissolve, or if ocean currents rapidly bring sediment to this section of the ocean, then burial can be gradual.This example does not contradict my primary point. To become a fossil, the skeletal remains must persist long enough to be buried. Any organisms whose remains happen to find a region of the world where skeletons can persist for a long period can take their own sweet time getting buried. But in most parts of the world, including beneath the sea, the lifetime of a skeleton exposed to the elements and scavaging is relatively short. After a hundred years I would expect even a skeleton the size of a while to have dissolved, and since in most parts of the world sedimentation rates don't exceed a couple inches per century, burial still requires special conditions.--Percy

And even burial doesn't guarantee preservation. Figure out how many people have lived and died in post-Roman Europe (where the dead are routinely buried) and try to find all of those skeletons.In most cases, even buried bone will decompose in a couple of centuries.

Jon, so does that mean whale and fish fossilization should not be so rare because all we need is for the bones of the fish to sink?If that's the case, we should expect nearly all of the aquatic transitional species to be available, somewhere, in great numbers.Correct, or not?

I do too, especially since whales float when dead, and you are right about the extreme corrosiveness of salt water. Probably what they saw was either some whale bones recently fallen, which somehow stayed intact, maybe over very call water, or just something they thought was a whale bone.It could be though that some folks caught a whale or something like that, stripped it at sea, and then sunk the bones to make sure no evidence linked them to poaching.But then again, I don't trust anything coming out of TalkOrigins.

Randman, you gave specific quantities for the numbers of fossils that should be found.You have been asked to show your development of those numbers or retract them.Do you have time yet?

Let's see if we can make some estimates on how complete the fossil record might be:from : Canadian Biodiversty: SpeciesThere are currently about 4,500 mammal species alive today.Let's assume a species "lives" for an average of 5 Myrs (I read it somewhere -pick another number if you don't like it).That suggests that since the end of the cretaceous and the "age of mammals" starting we should have had about (65/5) * 4500 = 58,000 separate mammal species. Subtract 4500 for the current ones gives 53,500 extinct species.Now the question is how many have we found?That is a harder answer to track down. You suggested the answer should be 90% or 48,000. I suggest that you are off by about an order of magnitude. I'm not at all sure of how to prove that though.

Apparently not. Read about whale falls:
Whale fall | NatureHow do those little Osedax critters fit into a "created kind?"

Lit:
It depends a lot on what sort of fossil you're considering. Coal, for example, is sort of a huge hodgepodge of fossils, very often with plant traces preserved. A bed of it typically formed over hundreds or thousands of years in the floor of a swamp, in a stable, unchanging environment where the bed just never got enough oxygen to destroy the peat as it accumulated. Fossils like the Archaeopterex at Selnhofen, Germany had the luck to sink into the oxygen-free (or hydrogen sulfide-rich) bottom of a calm pond or lagoon, and the got buried pretty slowly by carbonate ooze raining from above. The Burgess Shale fossils from Field, BC were apparently carried into deep water from their shallow home and buried quickly in a submarine landslide. There's no single mode of fossil preservation.

from: http://www.madsci.org/.../archives/aug97/871343510.Ev.r.html I don't know where they get the underlying numbers but this is a start.Of course, species that are larger, lived later etc. are more likely to be preserved I would guess.