Smith's colourful and sophisticated geological map was based on his astute observation that rock layers (strata) could be identified by the fossils they contain. He noticed that the layers always ...
Formation - A formation is a set of rock layers that consists dominantly of a certain rock type or combination of types. Fossiliferous Limestone - Limestone that contains abundant fossils. Fossils - ...
that cut across layers after the rocks were deposited. This is the principle of cross-cutting relationships. The principle states that any geologic features that cut across strata must have formed ...
Understanding geology is critical to studying paleontology because fossils are preserved ... Mudstone, shale, and limestone are examples of sedimentary rock likely to contain fossils. As the layers of ...
The lake bottom is stacked with thin layers of clay called varves that provide a geological record of the past 70,000 years, much like growth rings of a tree. Mud continued to accumulate there ...