ANTLER OROGENY - A MEDITERRANEAN-TYPE OROGENY

The late Cenozoic thrust belts of the Apennine, Carpathian, and Hellenic systems of the Mediterranean region provide modern analogues for the middle Paleozoic Antler orogeny. Each of these young or active mountain belts formed in convergent systems in which thrusting occurred behind a zone of trench retreat, while a region of extension developed contemporaneously within the hanging wall of the subduction systems. Dynamic models that have been recently developed for these tectonic systems provide a basis for interpretation for the Antler belt. Many, if not all, of the geologic relations observed in the Antler belt, including the lack of a collided arc and subsidence of a broad extensional region behind the thrust belt, are also present within these young Mediterranean thrust-belt systems. If this interpretation is correct, then the entire Antler belt may have been preserved, with no need for other tectonic elements to have been present west of the Antler thrust belt and the Havallah basin.