Geochronology of Mexican mineral deposits. VIII: the Zacatepec polymetallic skarn, Oaxaca
Por:
Camprubi, Antoni, Cabrera-Roa, Miguel Angel, Gonzalez-Partida, Eduardo, Lopez-Martinez, Margarita
Publicada:
1 ene 2019
Categoría:
Earth and planetary sciences (miscellaneous)
Resumen:
The Zn-Pb-Ag(-W) skarn deposits at Zacate-pec (or Miiygixy) in Oaxaca
are associated with jocks of the Sierra Madre del Sur (SMS) magmatic
province, and located in its easternmost part, in southern Mexico. This
region consists of Eocene to Miocene calc-alkaline hypabyssal and
volcanic rocks, with intermediate to felsic compositions that intrude or
overlie Cretaceous carbonate sequences. Prograde mineralization in the
Zacatepec skarn deposits was dated by means of the Ar-40/Ar-39 method in
a sample of the granitic hypabyssal body, with which the formation of
these deposits is directly associated. The isochron ages thus yielded
are 17.52 +/- 0.14 Ma for biotite and 17.33 +/- 0.40 Ma for hornblende.
Such ages are in accordance with several other magmatic-hydmthermal
deposits (epithermal. skarn. and porphyry-type deposits) that are hosted
by Miocene rocks in central Oaxaca state. Deposits in the region with
known ages for Miocene hypabyssal rocks with which they are closely
related are Taviche,Lachigalla, Cobre Grande, Aurena, Natividad,
Altagracia-Aguila-Arista, Santa Margarita-Azucena, and Guiclavazar. The
plausible ages for these ore deposits determine a time bracket between <
23.8 and < 13.01 Ma (early to middle Miocene) that can be considered as
favorable for the finding of magmatic-hydmthermal car deposits. The
latter can be tentatively used to define a new metallogenic period that
corresponds to a new metallogenic province, for which the rocks derived
from the Miocene magmatism of the SMS constitute the metallotect.
Although such metallogenic activity has not been altogether overlooked,
no previous papers have focused on its relevance and extent in space and
time. Therefore, this province constitutes the fifth Miocene mineralized
region known in Mexico. besides the southernmost Sierra Madre
Occidental, the Trans-Mexican Volcanic Belt, the Gulf of California. and
the alkaline province in Chiapas.
Filiaciones:
Camprubi, Antoni:
Univ Nacl Autonoma Mexico, Inst Geol, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Instituto de Geología, Universidad Nacional Autónoma de México. Ciudad Universitaria, Coyoacán, CDMX, 04510, Mexico
Cabrera-Roa, Miguel Angel:
Univ Nacl Autonoma Mexico, Ciencias Tiena, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México. Ciudad Universitaria, Coyoacán, CDMX, 04510, Mexico
Gonzalez-Partida, Eduardo:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Blvd Juriquilla 3001, Queretaro 76230, Qro, Mexico
Centro de Geociencias, Universidad Nacional Autónoma de México. Boulevard Juriquilla 3001, Querétaro, Qro., 76230, Mexico
Lopez-Martinez, Margarita:
Ctr Invest Cient & Educ Super Ensenada, Carretera Ensenada Tijuana 3918, Ensenada 22860, Baja California, Mexico
Centro de Investigación Científica y Educación Superior de Ensenada. Carretera Ensenada-Tijuana No. 3918, Zona Playitas, Ensenada, B.C., 22860, Mexico
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