4.6 Article

Counterclockwise P-T evolution of the Aghil Range: Metamorphic record of an accretionary melange between Kunlun and Karakorum (SW Sinkiang, China)

Journal

LITHOS
Volume 105, Issue 3-4, Pages 365-378

Publisher

ELSEVIER SCIENCE BV
DOI: 10.1016/j.lithos.2008.05.011

Keywords

Metamorphic evolution; Pseudosections; Counterclockwise P-T path; Aghil Range; Sinkiang

Funding

  1. P.R.I.N. Cofin 2006

Ask authors/readers for more resources

This paper describes the metamorphic evolution and the tectonic significance of the Aghil Range, a poorly known terrane located between Kunlun and Karakorum north of K2 in the framework of western Tibet. The Aghil Range consists of different units separated by syn- to late-metamorphic thrusts and post-metamorphic faults of similar attitude; among other units, the Surukwat Complex is a composite sequence of thrust sheets trending WNW-ESE and steeply dipping SSW showing a general increase of metamorphic grade from lower to higher structural levels. P-T pseudosections and conventional thermobarometry of metapelites at the top of the Surukwat Complex tightly constrain the P-T path of this highest-grade metamorphic portion of the Aghil Range. The prograde path is characterized by an early increase in both P and T and by a later, nearly isothermal, increase in P, from 500<530 degrees C and 0.25 <0.40 GPa to 580<600 degrees C and 0.80 <0.90 GPa. The peak metamorphic event is constrained at 550<590 degrees C and 0.77 <0.91 GPa. The retrograde path is characterized by decompression associated to a slight cooling to T similar to 500 degrees C and P<0.5 GPa. Altogether, the petrology of the studied rocks suggests a P-T path with a narrow counterclockwise shape. The studied sequence could represent the result of the early subduction of an accretionary complex, interpreted further eastward according to a melange underthrusting model. As concerning the tectonic setting of this terrane, a number of geologic and petrologic similarities link the Aghil Range and the central Qiangtang metamorphic belt, suggesting that the Aghil Range is the possible NW extension of the Qiangtang microplate separating Kunlun from Karakorum. (C) 2008 Elsevier B.V. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.6
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available