Geological formation

A geological formation is a set of rocks or minerals that have characteristics in relation to its composition, age, national origin or other similar properties. It is the basic fundamental unit of lithostratigraphy for the appointment of a group of rocks. To be classified as training, this set of rocks needs, and is distinguishable from other sets of rocks, have wide geographic distribution enough to be individually mappable in surface and / or subsurface. Formations are not defined by the thickness of the extracts of rock that form and therefore the thickness of formations can vary widely. A formation can be subdivided into members or clustered in groups.