| Journal: | Boletín de la Sociedad Geológica Mexicana |
| Database: | PERIÓDICA |
| System number: | 000384857 |
| ISSN: | 1405-3322 |
| Authors: | Alaníz Alvarez, Susana Alicia1 Nieto Samaniego, Angel Francisco |
| Institutions: | 1Universidad Nacional Autónoma de México, Centro de Geociencias, Querétaro. México |
| Year: | 2005 |
| Volumen: | 57 |
| Number: | 1 |
| Pages: | 65-82 |
| Country: | México |
| Language: | Español |
| Document type: | Revisión bibliográfica |
| Approach: | Analítico, descriptivo |
| Spanish abstract | Dos fronteras tectónicas del centro de México 65 B oletín de la S ociedad G eoló G ica M exicana V olu M en c on M e M orati V o del c entenario G rande S F rontera S t ectónica S de M éxico t o M o l V ii , nú M . 1, 2005, p . 65-82 El sistema de fallas Taxco-San Miguel de Allende y la Faja Volcánica Transmexicana, dos fronteras tectónicas del centro de México activas durante el Cenozoico Susana A. Alaniz-Álvarez * , y Ángel Francisco Nieto-Samaniego Centro de Geociencias, Universidad Nacional Autónoma de México, Campus Juriquilla, Apartado Postal 1-742, Querétaro, Qro., 76001, México. * alaniz@geociencias.unam.mx Resumen La Faja Volcánica Transmexicana se ha reconocido como un arco volcánico que atraviesa México de la costa pacífica al Golfo de México, con actividad volcánica y fallamiento normal desde el Mioceno al Reciente. Se ha planteado que la oblicuidad del arco volcánico con la trinchera es debida a la geometría de la subducción, cuyo ángulo de inclinación varía haciéndose menor hacia el oriente. Por otra parte, se ha propuesto que la Faja Volcánica Transmexicana se ubica sobre una zona de debilidad preexistente. En este trabajo se discuten los eventos de deformación cenozoicos ocurridos al norte y sur de la Faja Volcánica Transmexicana para identificar el tiempo en el que ésta actuó como zona de discontinui - dad y también para determinar la presencia del campo de deformación precursor del emplazamiento del arco volcánico. Utilizamos como una de las referencias el sistema de fallas Taxco-San Miguel de Allende, ya que es la única estructura reconocida que atraviesa el arco volcánico y de la cual se ha estudiado con detalle su evolución estructural. En la Mesa Central, al norte de la Faja Volcánica Transmexicana, la deformación extensional postlaramídica ha ocurrido en tres eventos relativamente discretos durante el Eoceno, Oligoceno y Mioceno-Reciente. Los tres eve |
| English abstract | The Transmexican Volcanic Belt has been recognized as a major volcanic arc which crosses Mexico from the Pacific coast to the Gulf of Mexico. This volcanic arc had normal faulting and volcanism since Miocene. It has suggested that the volcanic arc is not parallel to the Mesoamerican trench because the subduction angle varies being gentler to the east. Also it has been proposed a preexisting zone of weakness below the Transmexican Volcanic Belt. In this work we present the deformation events that have been recorded north and south of the Transmexican Volcanic Belt in order to identify the time in which this zone began to be a crustal discontinuity and also to determine the deformation field precursor of the emplacement of the volcanic arc. We use as a reference the studies along the Taxco-San Miguel de Allende because it is the only recognized structure that crosses the Transmexican Volcanic Belt. In the Mesa Central, north of the Transmexican Volcanic Belt, the postlaramidic deformation occurred in three extensional events during the Eocene, Oligocene and Miocene to Recent. The three events liberated extension in two horizontal directions and shortening in the vertical direction. The Eocene event was extensional but the directions of the principal extensions are not very well known. The Oligocene event was the most important; it extended 20% in the ~ENE-WSW direction. This event migrated toward west, finishing in the opening of the California Gulf, and also migrated toward south-southeast to the Transmexican Volcanic Belt. The most recent event, active since middle Miocene, has been developed in the Transmexican Volcanic Belt and its northern boundary. In the Sierra Madre Oriental, east of the Mesa Central and north of the Transmexican Volcanic Belt, the Cenozoic deformation has been minimum. South of the Transmexican Volcanic Belt, in the Taxco region, there were two postlaramidic deformation events, mainly liberat |
| Disciplines: | Geociencias |
| Keyword: | Geofísica, Geología, Sismología y vulcanología, Faja Volcánica Transmexicana, Tectónica de placas, Actividad sísmica, Fallas tectónicas, Mioceno, Guerrero, Guanajuato, México |
| Keyword: | Earth sciences, Geology, Geophysics, Seismology and volcanology, Transmexican Volcanic Belt, Plate tectonics, Seismic activity, Graben, Miocene, Guerrero, Guanajuato, Mexico |
| Full text: | Texto completo (Ver PDF) |
