Structural pattern of the Todos Santos Coastal Plain, based on geophysical data

Abstract

A set of gravity and magnetic data taken within the Todos Santos Coastal Plain between 1962 and 2000 from land, sea and air is used to integrate the structural framework and tectonic model of this area. The present work collected all the available data, homogenized them, and maintained them at their original altitude. A new technique of joint inversion for gravity and magnetic data from three-dimensional structures was applied. As a result, a well-defined topographic map of the granitic-andesitic basement was obtained and previously unknown geological structures were depicted. Several cross-sections were made from the three-dimensional model obtained, establishing the Todos Santos Coastal Plain structural pattern as a typical pull-apart basin associated with a tectonic fore-arc during the subduction of the Farallón Plate in Late Mesozoic and Early Cenozoic time.