Coercivity and Vector Magnetization Analysis of Obsidian Samples from the Trans-Mexican Volcanic Belt

Urrutia-Fucugauchi, Jaime; Pérez-Cruz, Ligia

DOI: https://doi.org/10.5281/zenodo.1319731.

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Coercivity and Vector Magnetization Analysis of Obsidian Samples from the Trans-Mexican Volcanic Belt

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Jaime Urrutia-Fucugauchi, Ligia Pérez-Cruz • español

Abstract. This note presents initial results of a paleomagnetic study of obsidian from twenty localities in the eastern, central and western sectors of the Trans-Mexican volcanic belt in central Mexico. We focus on the coercivity and vector composition of the remanent magnetization, which are critical for paleodirectional and paleointensity studies. Alternating field demagnetization shows that obsidians carry single and two-component magnetizations residing in low- and high-coercivity magnetic minerals, with discrete and overlapping coercivity spectra. Magnetic minerals are likely iron-titanium oxides with fine-grain sizes characterized by pseudo-single domain states.

Keywords: Mesoamerica, Obsidians, Magnetic properties, Paleomagnetic record.

Reference:

Urrutia-Fucugauchi, J., L. Pérez-Cruz. 2017.
Coercivity and Vector Magnetization Analysis of Obsidian Samples from the Trans-Mexican Volcanic Belt. Arqueología Iberoamericana 35: 23-28. http://purl.org/aia/354.

Publication date: August 10, 2017.

Acknowledgments

We acknowledge the technical assistance by Victor Macias, Miguel Angel Diaz, Mariana Marca and Martin Espinosa.

About the authors

Jaime Urrutia-Fucugauchi (juf@geofisica.unam.mx), Professor, Geophysical Institute, UNAM, Mexico City. Ligia Pérez-Cruz (perezcruz@geofisica.unam.mx), Professor and Chair, Department of Geomagnetism and Geophysical Exploration, UNAM, Mexico City.

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