Why fossils of organisms (let’s say dinosaurs) found in rocks take the vertical space of rocks that supposedly formed over not decades, but hundreds, thousands years?


Were they simply just lying on the ground for so long, undisturbed by scavenger animals, wind and water?

In: 4

Often they were quickly buried in mud and sediment that then took thousands of years to fuse into the sedimentary rock we find them in today.
So yes, in a sense they were just sitting there fit hundreds and thousands of years untouched by scavengers mostly because scavengers couldn’t find them buried in the mud.

Fossils are formed in rare circumstances. Most life that dies is as you say eaten by animals, microorganisms etc.

If we look at land animals fossils occur primarily when the animal is guiltily buried. It can be from clay, sand, volcanic ash etc. So if an animal gets traped in a landslide or a flood, volcanic eruption the can be buried within seconds. It is occurrences like this that result in most fossils.

So the environment animal lives in has a huge effect on the probability of fossil formation. It is quite a lot of human fossils since we split from Chimpanzees but few if any Chimpanzee fossils during the same time. The reason is living in forest results in a lot fewer fossils compared to living in a savana where flash floods are a lot more common.

So a lot of sedimentary rock is the result of a thin deposit over time all of it is not. The deposit does not solidify directly so an animal can distribute clay or sand that is slowly deposited and get trapped and buried in it

If you look out at sea you can get areas with low oxygen content and very little life where stuff can sink down and remain quiet undisturbed until is complete buried

You mean the rocks containing the fossils, that are so much older than all the other rocks lying on top, can’t have reached the surface? Well, they do, because of constant mountain building, uplift and erosion that not only brings them closer to the surface, but wears away the younger rocks. It’s hard to imagine but erosional forces can removed thousands of meters of rock over a few million years.