Tectonics of the offshore Manzanillo and Tecpan Basins, Mexican Pacific, from heat flow, bathymetric and seismic data

Abstract

In the Manzanillo Basin data indicate a recent uplift associated with strike-slip faulting. Heat flow ranges between 20-35 mW/m2 (average of 28±6 mW/m2) in the western Manzanillo Basin and 51±7 mW/m2 in the eastern basin. Both areas are bound by strike-slip faulting with a vertical component. The low heat flow is attributed to a portion of the coastal batholith that may have moved seaward along left-lateral faults in the Jalisco Block. The average heat flow value in the eastern portion is typical of the continental slope of the Middle American Trench; as measured off Tecpan, Guerrero, at an average of 55±8 mW/m2. High heat flow (>100 mW/m2) was found on the oceanic slope of the Middle American Trench. It is attributed to the younger age of the oceanic crust and/or to surface hydrothermal and local magmatic sources in the area of the El Gordo Graben. -from Authors