New insights into the history and origin of the southern Maya block, SE Me??xico: U-Pb-SHRIMP zircon geochronology from metamorphic rocks of the Chiapas massif

Weber, B.; Iriondo, A.; Premo, W. R.; Hecht, L.; Schaaf, P.

Abstract:

The histories of the pre-Mesozoic landmasses in southern Me??xico and their connections with Laurentia, Gondwana, and among themselves are crucial for the understanding of the Late Paleozoic assembly of Pangea. The Permian igneous and metamorphic rocks from the Chiapas massif as part of the southern Maya block, Me??xico, were dated by U-Pb zircon geochronology employing the SHRIMP (sensitive high resolution ion microprobe) facility at Stanford University. The Chiapas massif is composed of deformed granitoids and orthogneisses with inliers of metasedimentary rocks. SHRIMP data from an anatectic orthogneiss demonstrate that the Chiapas massif was part of a Permian (??? 272 Ma) active continental margin established on the Pacific margin of Gondwana after the Ouachita orogeny. Latest Permian (252-254 Ma) medium- to high-grade metamorphism and deformation affected the entire Chiapas massif, resulting in anatexis and intrusion of syntectonic granitoids. This unique orogenic event is interpreted as the result of compression due to flat subduction and accretionary tectonics. SHRIMP data of zircon cores from a metapelite from the NE Chiapas massif yielded a single Grenvillian source for sediments. The majority of the zircon cores from a para-amphibolite from the SE part of the massif yielded either 1.0-1.2 or 1.4-1.5 Ga sources, indicating provenance from South American Sunsa??s and Rondonian-San Ignacio provinces. ?? Springer-Verlag 2006.

Genre:

Article

ProdID:

70029963

Citation Author:

Weber, B.; Iriondo, A.; Premo, W. R.; Hecht, L.; Schaaf, P.

Citation Contributing Office:

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

269

Citation Issue:

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

International Journal of Earth Sciences

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

Citation Projection:

Citation Public Comments:

Citation Publisher:

Citation Series:

Citation Series Code:

Citation Series Number:

Citation Search Results Text:

New insights into the history and origin of the southern Maya block, SE Me??xico: U-Pb-SHRIMP zircon geochronology from metamorphic rocks of the Chiapas massif; 2007; Article; Journal; International Journal of Earth Sciences; Weber, B.; Iriondo, A.; Premo, W. R.; Hecht, L.; Schaaf, P.