Amanz Gressly (17 July 1814 – 13 April 1865) was a Swiss geologist and paleontologist. He introduced the use of the term facies in geology, and is considered one of the founders of modern stratigraphy and paleoecology. From 1853 he served as a geologist during the construction of rail tunnels through the Jura Mountains. In 1859 he was sent by Eduard Desor to Cette on the Gulf of Lyon in order to investigate the mode of life of marine organisms, and in 1861, with Carl Vogt and others, he embarked on a scientific expedition that took him to the North Cape, Jan Mayen and Iceland.