The Great Retreat of the Sea (page 1)


Derived from the greek words oros for mountain and geneia for birth, orogeny is the scientific term used to describe mountain building events. The “birth” of the Rocky Mountains is named the Laramide Orogeny, which is specific to the very first uplift of the mountains. Geologists refer to this period of time as the Laramide age, a long period of mountain building in the late Mesozoic and early Cenozoic eras.

Dickinson, W.R., M. A. Klute, M. J. Hayes, S.U. Janecke, E.R. Ludin, M.A. McKittrick, and M.D. Olivares (1988) Paleogeographic and paleotectonic setting of Laramide sedimentary basins in the central Rocky Mountain region. Geological Society of America Bulletin, v. 100, p. 1023-1039, fig. 10.