The oldest fossils are those found in deeper layers. This is because sedimentation is a sequential process that increases the original ground level. Thus, the soils in the most superficial layers have suffered less sedimentation impacts, because they are younger.
Fossils are records of living things that existed in the past and were somehow preserved. These living things may be preserved in rocks, sand, ice and, believe me, even within another fossil. Dinosaurs are the big stars when we talk about fossils. Who has never dreamed of discovering a large dinosaur skeleton?
