Paleomagnetism of Plio-Quaternary basalts in the Jalisco block, western Mexico
The interior of the Jalisco block, western Mexico, is disrupted by several NW-SE to NESWoriented grabens and associated recent alkaline volcanics which are bounded byWNW oriented regional lineaments. The geometry of these features suggests deformationfrom a right-lateral shear couple, consistent wit...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 1997 |
| País: | México |
| Institución: | Universidad Nacional Autónoma de México |
| Repositorio: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:56836103 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=56836103 |
| Access Level: | acceso abierto |
| Palabra clave: | Ciencias de la Tierra Jalisco Block paleomagnetism |
| Sumario: | The interior of the Jalisco block, western Mexico, is disrupted by several NW-SE to NESWoriented grabens and associated recent alkaline volcanics which are bounded byWNW oriented regional lineaments. The geometry of these features suggests deformationfrom a right-lateral shear couple, consistent with NW motion of the Jalisco block relativeto the North American plate. A paleomagnetic study was carried out in the Mascotagraben, the Talpa de Allende graben, and the San Sebastián volcanic field. Results from16 sites (D=354.6ø, I=33.3ø, k= 18.1, a95= 8.9ø) agree with the expected North Americadirections. Therefore, no significant recent regional displacement or rotations were found.However, the dispersion of paleomagnetic site means is greater than that expected fromsecular variation alone, suggesting that differential block rotations may have taken place.Volcanism within the Talpa de Allende graben and the southern part of the Mascotagraben is probably older than 0.78 Ma as evidenced by the discovery of four reverselymagnetized lava flows. |
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