Low Angle Contact Between the Oaxaca and Juárez Terranes Deduced From Magnetotelluric Data
Autor: | Jorge Arzate-Flores, Victor H. Márquez-Ramírez, Roberto S. Molina-Garza, Fernando Corbo-Camargo |
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Rok vydání: | 2016 |
Předmět: |
geography
geography.geographical_feature_category 010504 meteorology & atmospheric sciences Subduction Crust Fault (geology) 010502 geochemistry & geophysics 01 natural sciences Tectonics Geophysics Basement (geology) Geochemistry and Petrology Magnetotellurics Trench Petrology Seismology Geology 0105 earth and related environmental sciences Terrane |
Zdroj: | Pure and Applied Geophysics. 173:3357-3371 |
ISSN: | 1420-9136 0033-4553 |
Popis: | We present the electrical resistivity model along a profile perpendicular to the Middle America trench in southern Mexico that reveals previously unrecognized tectonic features at upper to mid-crustal depths. Our results support the hypotheses that the upper crust of the Oaxaca terrane is a residual ~20 km thick crust composed by an ~10 km thick faulted crustal upper layer and an ~10 km thick hydrated and/or mineralized layer. Oaxaca basement overthrust the younger Juarez (or Cuicateco) terrane. The electrical resistivity model supports the interpretation of a slab subducting at a low angle below Oaxaca. Uplift in the Oaxaca region appears to be related to fault reactivation induced by low angle subduction. In the Juarez terrane, isostatic forces may contribute to uplift because it is largely uncompensated. In the Sierra Madre del Sur, closer to the coast, uplift is facilitated by slab-dehydration driven buoyancy. Both gravity and resistivity models are consistent with a thinned upper crust in the northeast end of the profile. |
Databáze: | OpenAIRE |
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