Paleomagnetism and Paleointensity of the Michoacan-Guanajuato Volcanic Field, Mexico
Abstract
We report detailed paleodirectional and paleointensity study from 24 volcanic units (Late Pliocene to Present) from the Michoacan-Guanjuato volcanic field (MGVF). The MGVF belongs to Transmexican volcanic belt and contains over 1000 late Quaternary volcanic centers. Almost 90 percent of them are cinder cones. Single component, linear demagnetization plots were observed in most cases. Seven sites yield reverse polarity magnetization while fifteen volcanoes are normally magnetized. Sixteen samples, from three volcanoes, yield reliable paleointensity estimates with the site-mean virtual dipole moments (VDM) ranging from 7.3 to 12.2 x 1022 Am2. Mean VDM obtained in this study is 9.2 ± 0.8 x 1022 Am2 which is slightly higher than present day geomagnetic field strength.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSMGP44A..02C
- Keywords:
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- 1519 Magnetic mineralogy and petrology;
- 1521 Paleointensity;
- 1522 Paleomagnetic secular variation;
- 1560 Time variations: secular and long term