Regional earthquakes in northern Tibetan Plateau: Implications for lithospheric strength in Tibet
- 15 October 2010
- journal article
- Published by American Geophysical Union (AGU) in Geophysical Research Letters
- Vol. 37 (19)
Abstract
A total of 400 regional earthquakes were located in northern Tibetan Plateau from data recorded by INDEPTH‐IV and PKU Eastern Kunlun arrays from May 2007 to June 2009. The distribution of these earthquakes is compatible with a continuously deforming Tibetan lithosphere. Most earthquakes occur at a depth range of 0‐15 km, but no event is deeper than 30 km. This observation strongly supports the existence of a hot and weak lower crust beneath the northern Tibet. The crustal seismogenic zone appears slightly thicker beneath the northern Tibet than in the southern plateau, possibly reflecting a difference in the rheological (dry vs. wet) structure of the crust. The absence of lower crustal and uppermost mantle earthquakes in northern Tibet is consistent with a localized asthenospheric upwelling under the Qiangtang and Songpan‐Ganze terranes. Finally, the lack of mantle earthquakes should be fully addressed in any models of subduction in northern Tibet.Keywords
This publication has 25 references indexed in Scilit:
- Underplating in the Himalaya-Tibet Collision Zone Revealed by the Hi-CLIMB ExperimentScience, 2009
- Rheology of the Lower Crust and Upper Mantle: Evidence from Rock Mechanics, Geodesy, and Field ObservationsAnnual Review of Earth and Planetary Sciences, 2008
- Post-collisional, Potassic and Ultrapotassic Magmatism of the Northern Tibetan Plateau: Constraints on Characteristics of the Mantle Source, Geodynamic Setting and Uplift MechanismsJournal of Petrology, 2006
- Broadband Seismic Noise Analysis of the Himalayan Nepal Tibet Seismic ExperimentBulletin of the Seismological Society of America, 2005
- Precise temperature estimation in the Tibetan crust from seismic detection of the α-β quartz transitionGeology, 2004
- Seismicity of Central Tibet from Project INDEPTH III Seismic RecordingsBulletin of the Seismological Society of America, 2003
- Present-day deformation of the Qaidam basin with implications for intra-continental tectonicsTectonophysics, 1999
- Intermediate depth earthquakes beneath the India‐Tibet Collision ZoneGeophysical Research Letters, 1996
- Seismic tomography of northern Tibet and Kunlun: Evidence for crustal blocks and mantle velocity contrastsEarth and Planetary Science Letters, 1996
- Thermal evolution of the Gangdese batholith, southern Tibet: A history of episodic unroofingTectonics, 1995