Abstract
The Karakoram-Jiali Fault Zone (KJFZ) comprises a series of right-lateral shear zones that southerly bound the eastward extrusion of northern Tibet relative to India and stable Eurasia. Here we present new 40Ar/39Ar age data from the Pqu and Parlung faults, two easternmost branches of the Jiali fault zone, which indicate a main phase of the KJFZ shearing from ∼ 18 to 12 Ma. Thus, the Tibetan eastward extrusion bounded by principal strike-slip fault zones started and was probably most active around the middle Miocene, an interval marked also by active east-west extension in southern Tibet. The coincidence of these two tectonic events strongly suggests a common causal mechanism, which is best explained as oblique convergence between India and Asia. Under the framework of this mechanism, the extension in southern Tibet is not a proxy for the plateau uplift. The KJFZ activity was furthermore coincident with right-lateral displacements along the Gaoligong and Sagaing faults in southeast Asia. This defines a Miocene deformation record for the regional dextral accommodation zone that, in response to the continuing India-Asia collision, may have accounted for the initiation and prolonged history of clockwise rotation of the Tibetan extrusion around the eastern Himalayan Syntaxis.
Original language | English |
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Pages (from-to) | 185-194 |
Number of pages | 10 |
Journal | Earth and Planetary Science Letters |
Volume | 205 |
Issue number | 3-4 |
DOIs | |
Publication status | Published - 2003 Jan 10 |
Keywords
- Ar-40/Ar-39 dating
- Eastern Himalayan Syntaxis
- Karakoram-Jiali fault zone
- Tibet
ASJC Scopus subject areas
- Geophysics
- Geochemistry and Petrology
- Space and Planetary Science
- Earth and Planetary Sciences (miscellaneous)