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Geologic Periods

Definition

Geologic periods are one subdivision of geologic time enabling cross-referencing rocks and geologic events from place to place. These periods form elements of a hierarchy e.g., eons, eras, periods, epochs and ages.

Analogy

Think of geologic periods like chapters in a book. Each chapter represents a different period with its own unique events, characters (organisms), and settings (environments).

Related terms

Geologic Time Scale: A system of chronological dating that relates geological strata to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events in geologic history.

Stratigraphy: The branch of geology concerned with the order and relative position of strata and their relationship to the geological time scale.

Plate Tectonics: The theory explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates that move slowly over the underlying mantle. This movement can influence climate change which can lead to new geologic periods.