Cordilleran Section - 108th Annual Meeting (29–31 March 2012)

Paper No. 2
Presentation Time: 14:50

TECTONIC SYSTEMS OF MEXICO, 50 YEARS OF DISCOVERY AND INNOVATION


ORTEGA-GUTIÉRREZ, Fernando, Geología Regional, Instituto de Geología, UNAM, Ciudad Universitaria, Coyoacan, México D.F, Mexico, 04510, Mexico, fortega@unam.mx

Since the seminal GSA publication of the Tectonic Map of Mexico in 1961, five decades of continued research of the Mexican geology not only witnessed major changes of paradigms in earth science and tectonic theory, but the geology of Mexico also has grown as a natural laboratory for the testing and advance of central elements of the new science of plate tectonics. Features like the Gulf of California in the early sixties served to convince a reluctant North American geology community to fully accept the new tectonic paradigm by revealing the actual birth of oceanic crust and the lateral displacement of continental blocks on the surface of the Earth. Moreover, the Gulf of Mexico on the eastern margin of the continent, for many decades was o conundrum for the reconstruction of this complex region of Pangea, and perhaps the innovative concept of tectonostratigraphic terranes was inspired or fueled by these questions: Where was the vast extension of pre-Mesozoic crust of southern Mexico and Central America when Pangea assembled? And, was the Gulf of Mexico a remnant ocean left over by this supercontinent assembly?

Fifty years after that tectonic portray of Mexico appeared, essentially before the onset of plate tectonics, we have now endeavored in the challenging task to identify, classify, map, and interpret the tectonic constitution of the 4 million squared kilometers of continental and oceanic crust of the country in terms of seven major tectonic categories, selected on the basis of modern geodynamic principles: basins, arcs, platforms, shallow orogens, deep orogens, batholiths, and composite provinces of the continental crust, together with the most distinctive structures of the oceanic crust: rifts, active or abandoned ridges, trenches, transform faults, seamounts and emerged volcanoes.

During the following three years, a top-quality research team belonging to most of the main Earth Science institutions of Mexico will tackle this project recently funded by CONACyT, with the final purpose of producing a new Tectonic Map of Mexico at the scale 1:2 000 000, a one volume book dealing with the tectonic makeup, origin and evolution of this country, and rising a representative collection of type-rocks selected across three transcontinental profiles that will traverse the majority of the tectonic units targeted by the project.