Science / Geology / Stratigraphy: The science of the description, correlation, and classification of strata in sedimentary rocks, including the interpretation of the depositional environments of those strata.

System (Stratigraphy)

Science / Geology / System (Stratigraphy): A stratigraphic unit larger than a series, consisting of all the rocks deposited in one period of an era. MORE

Magnetic Stratigraphy

Science / Geology / Magnetic Stratigraphy: The study and correlation of polarity epochs and events in the history of the Earth's magnetic field as contained in magnetic rocks. MORE


Science / Chemistry / Formation: A reaction that forms one mole of a compound from its elements in their most stable forms. For example, the formation reaction for water is H2(g) + ??O2 rightarrow H2O(ell). MORE

Time Scale

Science / Geology / Time Scale: The division of geologic history into eras, periods, and epochs accomplished through stratigraphy and paleontology. MORE