Pre-spreading history of the Cayman Trough

Abstract

The spreading history at the Cayman Trough oceanic axial ridge is well constrained to have begun during the Eocene. The ridge developed between the Oriente Transform Fault (OTF) to the north and the Swan Transform Fault (STF) to the south. Transform displacement has been concentrated since inception of the ridge east of the spreading ridge along the OTF and west of the ridge along the STF, while displacement has ceased along the western OTF and the eastern STF. Since the axial ridge formed after initiation of left lateral strike-slip motion along the transform system, evidence should exist for this pre-ridge displacement when the OTF and SFZ were a single entity (the Oriente-Swan Fault Zone, or OSFZ). Evidence for this pre-ridge displacement along the western OSFZ, as well as for southward migration of the active North American-Caribbean plate boundary is found as pull-apart basins, fault lineaments and drag folds across a wide swath of the Maya Block in Belize, Guatemala and Mexico.

AAPG Datapages/Search and Discovery Article #90330©2018 AAPG Hedberg: Geology of Middle America – the Gulf of Mexico, Yucatan, Caribbean, Grenada and Tobago Basins and Their Margins “Integration of the geology of the area from the southern onshore of North America to the northern onshore of South America”, Siguenza, Guadalajara, Spain, July 2-5, 2018