The shell membrane is a thin tissue structure upon which the mineralized shell is built.
It is called replacement .
A trace fossil can be anything from a coprolite (faeces) to a footprint. It is anything which proves the creature's existence without being the actual creature itself. For example, an ammonite shell is proof of its individual existence, but its faeces give us little information about its appearance. A fossil could be a cast, mold, or true form fossil.
Nothing. Something must contain carbon to be carbon dated. By definition fossils are mineralized and contain no carbon.
brachiopod
All of them, in fact. There are no bits of flesh still present in a millions-of-years-old fossil; it's all mineralized.
The strata or rock layers of the grand canyon walls are undisturbed. As such, a layer of rock containing a fossil, that is below an overlying rock layer will be older.
A hard shell organism have more of a chance to become a fossil .
Organisms with hard parts such as a mineralized shell, like a trilobite or ammonite, are much more likely to become fossilized than animals with only soft parts.
cover fossil (or japanese translation shell fossil) then tirtouga (level 37) carracosta.
When an ancient animal for example Tortoise or snail die in its shell....years later another tortoise or snail can fit itself in the fossil shell.
The plant or animal must be encased in a substance that prevents destruction or erosion. Ice, tar, or layers of mud or clay can isolate the remains from sunlight, air, and consumption by other lifeforms. Over time, a mineralized form or a rock cast will result in a fossil or fossil imprint.