Tectonothermal History of the La Noria-Las Calaveras Region, Acatlan Complex, Southern Mexico: Implications for Paleozoic Tectonic Models
The Acatlán Complex of southern Mexico exposes the country's largest assemblage of Paleozoic rocks, the evolution of which has traditionally been linked to the Appalachian orogen and the closure of Iapetus. Previous studies in the La Noria-Las Calaveras area have proposed that the entire complex was deformed in the greenschist facies during a Late Devonian (Mixtecan) orogeny; based on a U-Pb lower intercept age of ~370 Ma for the La Noria granite, interpreted to have syntectonically intruded the complex’s uppermost unit, the Tecomate Formation, during this event. As a result of structural, geochemical and geochronological reassessment of the area, however, it is concluded that the complex records Late Devono-Mississippian, Early Permian and Triassic (?) greenschist facies deformational events. This finding affects traditional Paleozoic tectonic models for the Acatlán Complex, by suggesting that the complex’s tectonothermal evolution coincides with the closure of the Rheic Ocean during the final assembly of Pangea.
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:northern acatlan complex southern mexico tectonothermal history la noria las calaveras area greenschist facies orogeny three deformational events
Date of Publication:01/01/2006