| Summary: | Instituto de Investigación en Metalurgia y Materiales. Maestría en Geociencias y Planificación del territorio We performed the characterization of the magnetic properties and magnetic stratigraphy of various lithological units of the Sierra de Mil Cumbres (SMC) (16 sites, 145 cores, 321 samples). The purpose of this study was to get the first paleomagnetic data for early Miocene because up to now only had data for the last 11 Ma. Regional scale magnetic polarities are established through correlation with the Geomagnetic Polarity Time Scale (GPTS). In addition, possible tectonic rotations through the comparison of the mean paleodirections obtained for the SMC with the expected directions (recalculated) reference pole for the North American craton Early Miocene were determined. We obtained, by Virtual Geomagnetic Pole (VGPs), a new paleomagnetic pole consistent that agree with other Early Miocene reliable estimates for the Trans-Mexican Volcanic Belt. Since different rock magnetic experiments, we determined that the minerals responsible for the magnetization are most probably Ti-poor titanomagnetites. Although, in some cases we observed maghemitization effects and/or intergrowths with titanohematite phases resulted from hydrothermal alteration. These inferences were tested, without detailed work, with some observations of magnetic opaque minerals under reflected light and optical microscope. This paper is a contribution to the characterization of the geomagnetic field and its variations, and at the same time increase the paleomagnetic database for Mexico. Se efectuó la caracterización de las propiedades magnéticas y de estratigrafía magnética de varias unidades litológicas de la Sierra de Mil Cumbres (SMC) (16 sitios, 145 núcleos, 321 especímenes). El propósito del trabajo fue de estudiar los primeros datos paleomagnéticos para el Mioceno temprano dado que hasta ahora solo se tenían datos para los últimos 11 Ma. Se estableció la escala de polaridades magnéticas regionales por medio de correlación con la Escala ...
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