The Extended Continental Crust West of Islas Marías (Mexico)

The crustal structure around the Islas Marías Archipelago has been debated for a long time. An important unresolved question is where Rivera-North American plate subduction ends and Tamayo fracture zone begins, from SE to NW. Results TsuJal project have shed light on northwesternmost part of Jalisco block structure. It now clear that Sierra de Cleofas Escarpment comprise northwestern continuation Middle America trench. However, other questions remain. In this paper, we present shallow deep crust upper mantle western region through integration multichannel seismic reflection, wide-angle bathymetric seismicity data, including records an amphibious network, OBS, portable stations, purposely deployed project, providing onshore-offshore transect 310 km length. Our findings disclose new evidence complex Rivera dips 8°–9° underneath NW as revealed by two profiles parallel Escarpment. Moreover, find five sedimentary basins active normal faults at edges tectonic structures E-W oriented West Ranges N-S trending Cleofas. Furthermore, beginning beneath North America. oceanic thickens submerges towards south while coupled with continental crust, 6 northern 15 in contact 24 coast southern them. Moho was not fully characterized because geometry transects, but low-velocity layer associated Plate observed Block. results constrain complexity area reveal structural features will be pivotal assess geohazards area.