The Eocene-Oligocene Nanchititla dike swarm, eastern Michoacan, Mexico
Por:
Chávez-Álvarez M.J., Cerca, Mariano, Lopez Martinez, Margarita, Origel-Gutierrez, Gabriel, Ferrari, Luca
Publicada:
9 dic 2020
Ahead of Print:
1 dic 2019
Resumen:
We present a geologic map for the Eocene-Oligocene Nanchititla mafic
dike swarm consisting of over 140 NNW-SSE trending dike segments; whose
emplacement was influenced by the left-lateral transtensional
deformation regime prevailing in southern Mexico during the Cenozoic.
The hosting rock is a mechanically heterogeneous continental sedimentary
sequence interbedded with volcanic rocks. Interaction among magma and
host rock promoted the formation of dike-sill systems, segmentation and
sinuous intrusions. Dike thickness observed is between 1 and 45 m with a
peak in the range from 1 to 5 m. Six giant dikes of more than 30 m thick
were documented. The 80% of the dikes have porphyritic textures rich in
plagioclase phenocrysts with size ranging from 0.5 to 2.5 cm. New and
compiled 40Ar-39Ar ages constrain the swarm emplacement between 30 and
34.5 Ma, whereas plagioclase phenocrysts entrained by the magma have
older ages between 35 and 42 Ma.
Filiaciones:
Chávez-Álvarez M.J.:
CONACyT, Instituto de Geofísica, Unidad Michoacan, Universidad Nacional Autónoma de México, Morelia, Michoacán, Mexico
Cerca, Mariano:
Laboratorio de Mecánica de Geosistemas, Centro de Geociencias, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, Mexico
Univ Nacl Autonoma Mexico, Ctr Geociencias, Lab Mecan Geosistemas, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Lopez Martinez, Margarita:
División de Ciencias de la Tierra, Centro de Investigación y Educación Superior de Ensenada, Ensenada, B.C., Mexico
Ctr Invest & Educ Super Ensenada, Div Ciencias Tierra, Ensenada, Baja California, Mexico
Origel-Gutierrez, Gabriel:
Geoinformática
GIS & Remote Sensing Consulting, Geoinformat ABC Map Mapping, Euripides, Mexico
Ferrari, Luca:
Laboratorio de Mecánica de Geosistemas, Centro de Geociencias, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, Mexico
Univ Nacl Autonoma Mexico, Ctr Geociencias, Lab Mecan Geosistemas, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Univ Nacl Autonoma Mexico, Inst Geofis, Unidad Michoacan, CONACYT, Morelia, Michoacan, Mexico
Open Access
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