CaltechAUTHORS
  A Caltech Library Service

Origin of the modern Chiapanecan Volcanic arc in southern México inferred from thermal models

Manea, Vlad C. and Manea, Marina (2006) Origin of the modern Chiapanecan Volcanic arc in southern México inferred from thermal models. In: Volcanic Hazards in Central America. Special papers (Geological Society of America). No.412. Geological Society of America , Boulder, CO, pp. 27-38. ISBN 9780813724126. http://resolver.caltech.edu/CaltechAUTHORS:20150204-102800248

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20150204-102800248

Abstract

In southern México, the subducting Cocos slab drastically changes its geometry: from a flat slab in central México to a ∼45° dip angle beneath Chiapas. Also, the currently active volcanic arc, the modern Chiapanecan volcanic arc, is oblique and situated far inland from the Middle America trench, where the slab depth is ∼200 km. In contrast, the Central America volcanic arc is parallel to the Middle America trench, and the slab depth is ∼100 km. A two-dimensional steady-state thermomechanical model explains the calc-alkaline volcanism by high temperature (∼1300 °C) in the mantle wedge just beneath the Central America volcanic arc and the strong dehydration (∼5 wt%) of the Cocos slab. In contrast, the thermal model for the modern Chiapanecan volcanic arc shows high P-T conditions beneath the coast where the extinct Miocene Chiapanecan arc is present, and is therefore unable to offer a reasonable explanation for the origin of the modern Chiapanecan volcanic arc. We propose a model in which the origin of the modern Chiapanecan volcanic arc is related to the space-time evolution of the Cocos slab in central México. The initiation of flat subduction in central México in the middle Miocene would have generated a hot mantle wedge inflow from NW to SE, generating the new modern Chiapanecan volcanic arc. Because of the contact between the hot mantle wedge beneath Chiapas and the proximity of a newly formed cold, flat slab, the previous hot mantle wedge in Chiapas became colder in time, finally leading to the extinction of the Miocene Chiapanecan volcanic arc. The position and the distinct K-alkaline volcanism at El Chichón volcano are proposed to be related to the arrival of the highly serpentinized Tehuantepec Ridge beneath the modern Chiapanecan volcanic arc. The deserpentinization of Tehuantepec Ridge would have released significant amounts of water into the overlying mantle, therefore favoring vigorous melting of the mantle wedge and probably of the slab.


Item Type:Book Section
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1130/2006.2412(02)​DOIArticle
http://specialpapers.gsapubs.org/content/412/27.abstractPublisherArticle
Additional Information:© 2006 Geological Society of America. Accepted 19 March 2006. Very helpful comments and suggestions by Jim Luhr, Mike Willis, and an anonymous reviewer were very important to improving this manuscript. We would also like to acknowledge support from the Gordon and Betty Moore Foundation. This is contribution 9129 of the Division of Geological and Planetary Sciences and contribution 33 of the Tectonics Observatory, California Institute of Technology.
Group:Caltech Tectonics Observatory
Funders:
Funding AgencyGrant Number
Gordon and Betty Moore FoundationUNSPECIFIED
Subject Keywords:Chiapanccan volcanic arc, thermal models, alkaline volcanism, flat subduction
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological and Planetary Sciences9129
Caltech Tectonics Observatory33
Record Number:CaltechAUTHORS:20150204-102800248
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20150204-102800248
Official Citation:Vlad C. Manea and Marina Manea Origin of the modern Chiapanecan Volcanic arc in southern México inferred from thermal models Geological Society of America Special Papers, 2006, 412, p. 27-38, doi:10.1130/2006.2412(02)
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:54367
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:04 Feb 2015 19:08
Last Modified:04 Feb 2015 19:08

Repository Staff Only: item control page