Outline of the Geology of Cuba

Abstract

Listen

Translate article

Cuba is approximately 700 miles long and 50 miles wide. It is divided into eight physiographic provinces which roughly correspond to geological features. The geological column ranges from Middle Jurassic to Pleistocene. Much of the Middle and Lower Cretaceous is missing or has not been identified. There was extensive Cretaceous volcanism. The Upper Cretaceous and Tertiary have an abundant, well-preserved fauna. The Eocene and Oligocene faunas are Old World in contrast to the Miocene fauna, which is New World in relationships. The Tertiary is well represented from the Paleocene through the Miocene. The Upper Cretaceous and the Paleocene are land-derived sediments of unknown geographical origin. The remaining are largely marls and limestones. There are both extrusive and intrusive rocks. Basic and acid rocks occur in both types. There are various structures of diverse ages. In the west is a large overthrust followed by two large anticlines to the east. A large overthrust area including the Trinidad Mountains and intrusions occupy the central part of the island. A broad syncline with extensive intrusions forms the eastern end, with a mass of meta-morphics lying at the extreme east. Cuba in its present form dates from late Miocene. Previously the area was occupied by scattered islands or was completely submerged. During late Cretaceous and the Paleocene, portions of what is now Cuba were part of a large land mass that extended as far south as Jamaica. Since assuming its present form, Cuba was submerged in the Pleistocene or Recent. This accounts for the paucity of land fauna on the island.