Structural constraints on the exhumation of the Tso Morari Dome, NW Himalaya

The Tso Morari culmination in the Ladakh region of northwest India is a large (>3,000 km²) structural dome cored by coesite-bearing rocks of Indian continental crustal affinity. As one of only two localities in the Himalaya where ultrahigh-pressure rocks have been found, the culmination offers important insights into the orogenic processes responsible for exhumation of subducted continental crust. New, 1:50,000 scale geologic mapping and structural analysis in the Tso Morari area reveals evidence for five distinct deformational events. Rather than simple, one step processes envisioned by investigators in many ultrahigh-pressure terrains, exhumation of the Tso Morari culmination was a polyphase process. From >90 km to mid-crustal depths, exhumation was accommodated by a diachronous set of rooted, ductile, extensional detachments that were active [approx.] 53-40 Ma. Beginning in the Late Oligocene, continued exhumation occurred by progressive unroofing along a younger, brittle-ductile detachment. Through a rolling-hinge mechanism similar to that proposed for many metamorphic core complexes of the North American Cordillera, this unroofing led to the development of the culmination into a NW trending structural dome.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Clark, Ryan J

Advisor dc:contributor.advisor

• Kip Hodges.

• Earth, Atmospheric, and Planetary Sciences.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/33724
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/33724

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/33724