fossils
Such remains are known as fossils if the sediment is changed over eons into a sedimentary rock.
fossils
Over time, any remains of living things in sediment may slowly harden and change into fossils trapped in the rock.
Cause they well be I stink
mold
Is natural gas formed by animal or plant remains
fossil fuels
Typically something dies and gets buried in sediment. Over time the sediment transforms to sedimentary rock and the remains of the dead plant or animal fossilizes. There are a few variants on this but that is the basic process.
You have to have the dead remains buried quickly and then never distroyed
mold
Ichnofossil, or an impression fossil. http://en.wikipedia.org/wiki/Trace_fossil
Organisms are buried under sediment.