Matt Formation

Matt Formation
Stratigraphic range: Early Oligocene,
TypeFormation
Unit ofNorth Helvetic Flysch
UnderliesBlattengrat Nappe, Wildflysch Nappe
OverliesElm Formation
Lithology
PrimarySlate, sandstone
Location
RegionCanton Glarus
CountrySwitzerland
Type section
Named forMatt, Switzerland
Named bySiegenthaler, 1974

The Matt Formation is an Early Oligocene-aged marine geological formation that outcrops in the Glarus Alps of the Canton of Glarus, Switzerland. It is most notable for its fossiliferous slates found near Engi, known as the Engi slates, Glarner Schiefer (Glarus Slate) or Glarner Fischschiefer ("Glarus fish slate"), which contain the well-preserved fossils of fishes, birds, and sea turtles. The metamorphization of the rock has led to many of the fossils appearing somewhat distorted.