layers of strata are deposited horizontally or nearly horizontally (Figure 2). Thus, any deformations of strata (Figures 2 and 3) must have occurred after the rock was deposited. The principle of ...

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 ...

It was through a letter dated March 30, 1579 that Giovanni Arduino announced the four orders that form the basis of ...