| In geology, a facies ( FAY-sheez; plural also facies) is a body of rock with specified characteristics, which can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formation), and the changes that may occur in those attributes over a geographic area.
It is the sum total characteristics of a rock including its chemical, physical, and biological features that distinguishes it from adjacent rock.The term facies was introduced by the Swiss geologist Amanz Gressly in 1838 and was part of his significant contribution to the foundations of modern stratigraphy, which replaced the earlier notions of Neptunism. |
