Question : If a fossil has survived 100 million years to be fond one day. How could it possibly still be in tact?
What I'm thinking is no fossil could possibly survive that long. With rates of erosion, volcanoes, earthquakes shaking them violently hundreds, maybe thousands of times over that time period no fossil could survive that long. Maybe I'm wrong but how could anything that long ago even a fossil stay in tact until now.
- asked by kevin s
All Answers: Answer #1Most fossils are solid rock (all the organic material that was originally in the creature'sremains have been replaced by minerals over theages). A rock lasts a long time.
- answered by nature_boy11
Answer #2
A 100 million year old fossil would bemid-Cretaceous, and not at all rare in the fossilworld. Fossils are usually hard animal parts likebones and calcareous shells, or imprints of plantstructures, that have been replaced by calcite orsilica to help preserve them. The soft tissueparts of animals (muscle, skin, and hair) areextremely rare. If a sedimentary rock can bepreserved that long without excessive metamorphismand deformation, then the fossil would bepreserved as well as its enclosing rocks. Ofcourse, if the sedimentary rock containing afossil was subjected to deformation (faulting andfolding) and metamorphism (heat and pressure),then it is unlikely the fossil would be preserved. That's what makes fossils rare - you won't findthem in igneous rocks or metamorphic rocks!
- answered by georock1959
Answer #3
The answer is that most don't survive. We onlyfind the lucky ones that have survived. If bonessurvived from every animal that ever lived, theupper layers of the Earth's crust would be full ofthem. Note how the broken down shells ofquadrillions of ancient sea creatures form massivemountains of limestone and those fantastic chalkcliffs. That gives you some idea of the amount ofanimals that have lived and died over the aeons. Fossils only form in extremely luckycircumstances, and fossils of larger animals arenot found intact in any case.
- answered by nick s
Answer #4
Stromatolite fossils have been found dating back approximately 3.5 billion years ago. They havebeen preserved in rock layers in the pilbararegions of Western Australia.
- answered by loza
Answer #5
As was already pointed out, fossil have becomerock, and so are not going to decay. The problemis that at the rate the continents are eroding,they would be washed into the ocean in just 10million years. So if the fossils are really thatold, they should be long gone, and the continentswith them. Geologists don't have an answer forthis problem so they just ignore it. The logicalanswer is that the continents are simply not thatold, but logic seems to have little to do with theage of the earth.
- answered by Donald K
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