Nw-mexvel: a Gps Crustal Deformation Model Based on Green's Functions for Northwestern Mexico

Abstract

The research examines and describes the interaction between the Pacific and North American Plates in Northwest Mexico using 12 years (2010-2021) of Global Positioning System (GPS) data from 33 free access continuous operating reference stations. The data was processed by GAMIT/GLOBK to contribute to the kinematic knowledge of this tectonic interaction. A bidimensional crustal deformation model was developed on a 15' x 15' grid based on Green's functions and elastic coupling. The proposed model NW-MEXVEL has been evaluated by direct point-to-point validation considering as a reference the GEODVEL global model. The displacements obtained in the NW-MEXVEL model adjusted to the ITRF14 are reliable for movements greater than 0.127 mm/year based on the root mean square error (RMSE) of modeled velocities versus measured velocities. Similarly, the model NW-MEXVEL for each tectonic plate has reliability for displacements over the Pacific Plate greater than 0.068 mm/year and for the North American Plate greater than 0.067 mm/year, even in the islands of the Gulf of California (Angel and Tiburon) and Guadalupe Island on the Pacific Plate. This is given by its estimation with regional data located in critical zones, in contrast to the global tectonic model. Finally, from the velocity fields, an average displacement was obtained of 44.72 ± 0.29 mm/year in the Northwest direction for the Pacific Plate fixed to the North American Plate and 45.34 ± 0.18 mm/year in the Southeast direction for the North American Plate fixed to the Pacific Plate. These velocity results are in agreement with previous studies.