Reconnaissance paleomagnetic investigation of cretaceous limestones from southern México

Paleomagnetic data from a total of 174 oriented samples collected from a400 m thick sequence of Cretaceous limestones from Oaxaca State, southern Mexico (-16.6°N, 97.0°W) were reported. The magnetic stability and vectorial composition were investigated by detailed alternating field and thermal demag...

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Detalles Bibliográficos
Autor: Urrutia Fucugauchi, J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1981
País:México
Institución:UNIVERSIDAD NACIONAL AUTÓNOMA DE MÉXICO
Repositorio:Geofísica Internacional
Idioma:español
OAI Identifier:oai:revistagi.geofisica.unam.mx:article/977
Acceso en línea:http://revistagi.geofisica.unam.mx/index.php/RGI/article/view/977
Access Level:acceso abierto
Palabra clave:Paleomagnetismo
Calizas
Cretácico
Oaxaca
México
Paleomagnetism
Limestone
Cretaceous
Mexico
Descripción
Sumario:Paleomagnetic data from a total of 174 oriented samples collected from a400 m thick sequence of Cretaceous limestones from Oaxaca State, southern Mexico (-16.6°N, 97.0°W) were reported. The magnetic stability and vectorial composition were investigated by detailed alternating field and thermal demagnetization. A selection procedure based upon directional stability of demagnetized vectors and within-site dispersion restricts the data population to 115 samples. All stable samples are normally magnetized, which is consistent with the geologic age suggested for the sequence of Albian-Cenomanian, within the normal polarity interval. The direction and pole position obtained are 348.7°, 23.0° (k = 27, α95=6.6°) y 78.4°N, 149.8°E (k = 38, A95 = 5.5°). The pole position apparently diverges from the corresponding segment of the North American apparent polar wander path, which may suggest the occurrence of relative tectonic movement between that part of Mexico and North America. The angular divergence is small, and at present, this is just considered as one of the possible tectonic events within the suggested theories for the evolution of Middle America.