Tectonic Analysis of the Southern of María Cleofas Island from Bathymetric and Seismic Data

Abstract

The TsuJal geophysical survey was conducted during the spring of 2014 with the aim to characterize the crustal structure of western Mexico. This geophysical experiment focused on active geological formations such as subduction, faults, and accretionary prisms, which are related to the seismic and tsunamigenic activity. In this work, we used seismic and bathymetric data to characterize the interaction between the Rivera plate (RP) and the North America plate south of Maria Cleofas Island. By defining the structural trends and subsurface geology, we sought to understand the complexity of the tectonic framework of western Mexico. A migrated seismic section and bathymetric maps were generated via the acquisition and processing of TsuJal geophysical data. Bathymetric data show major seafloor structures related to two basins (Tres Marias and TsuJal), one canyon (Cocodrilo Canyon), and an uplift structure with a north–south trend (Sierra de Cleofas [SC]). Seismic data reveal a compressional regime related to the movement of the RP at the westernmost end of the seismic section and lack of deformation in sediments within the two basins found adjacent to SC. From the results of our data analysis as well as corroborating literature, we interpret an underthrusting of RP beneath the North America plate, causing a compressional tectonic regime with the formation of palm-tree structures. The lack of deformation may be associated with a heated oceanic plate that facilitates the relative motion of the basement below the sediments.