Review of the last Cenozoic magmatic events in the north-central part of the Sierra Madre del Sur and their posible connection with the deep stratum in the Mexico Basin
Por:
Torres, EAG, Zenteno, DJM, Mori, L, Martiny, BM
Publicada:
1 ene 2015
Categoría:
Earth and Planetary Sciences (miscellaneous)
Resumen:
In this work we review the possible correlation between the deep subsoil
units of the Mexico Basin (MB), that are known through the lower
successions cut by wells, and the Cenozoic stratigraphic record previous
to the Trans-Mexican Volcanic Belt (TMVB), which is exposed in the
northern part of the Sierra Madre del Sur (SMS). South of the MB, recent
stratigraphic studies provide new geochronological data from some
eruptive centers of the northern-central sector of the SMS, such as the
Taxco and Huautla volcanic fields, and the Tilzapotla caldera. These
volcanic fields represent the last volcanic record of the Paleocene SMS
arc that developed before the inception of the TMVB. Based on
lithological analogies, the stratigraphic position and the thickness of
the obtained lithological record, the lower parts of the deep wells
drilled in the MB can be related to the distal units of the previously
mentioned volcanic centers. In the same way, in Tepoztlan and Malinalco
(states of Morelos and Mexico), located south of the MB, the first
volcanic episodes of the TMVB are exposed, with ages ranging from
similar to 22.8 and 18.8 Ma, that have been correlated by other authors
to the ages reported in various deep wells of the MB.
Based on the available geologic information, we consider that the
process of subsidence observed in the MB is contemporaneous with the
TMVB, and that it is not related to the Paleogene tectonics of the
region. The absence of significant volumes of volcanic or sedimentary
rocks of probable Paleogene age (generally less than 1000 m thick)
between the Neogene successions and the Cretaceous marines units in the
MB subsoil, strongly suggests that subsidence mainly took place during
the Neogene.
Filiaciones:
Univ Nacl Autonoma Mexico, Div Ingn Ciencias Tierra, Fac Ingn, Ciudad Univ, Mexico City 04510, DF, Mexico
Univ Nacl Autonoma Mexico, Inst Geol, Dept Geoquim, Mexico City 04510, DF, Mexico
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