Underplating in the Himalaya-Tibet Collision Zone Revealed by the Hi-CLIMB Experiment
John Náb
lek,1,*
György Hetényi,2,
Jérôme Vergne,2,
Soma Sapkota,3
Basant Kafle,3,
Mei Jiang,4
Heping Su,4
John Chen,5
Bor-Shouh Huang,6
the Hi-CLIMB Team||
We studied the formation of the Himalayan mountain range and
the Tibetan Plateau by investigating their lithospheric structure.
Using an 800-kilometer-long, densely spaced seismic array, we
have constructed an image of the crust and upper mantle beneath
the Himalayas and the southern Tibetan Plateau. The image reveals
in a continuous fashion the Main Himalayan thrust fault as it
extends from a shallow depth under Nepal to the mid-crust under
southern Tibet. Indian crust can be traced to 31°N. The
crust/mantle interface beneath Tibet is anisotropic, indicating
shearing during its formation. The dipping mantle fabric suggests
that the Indian mantle is subducting in a diffuse fashion along
several evolving subparallel structures.
2 Laboratoire de Géologie, École Normale Supérieure, CNRS-UMR 8538, 24 Rue Lhomond, 75005 Paris, France.
3 National Seismological Center, Department of Mines and Geology, Kathmandu, Nepal.
4 Institute of Geology, Chinese Academy of Geological Sciences, Beijing, People’s Republic of China (PRC).
5 Institute of Theoretical and Applied Geophysics, Peking University, Beijing, PRC.
6 Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan.
Present address: Earth Sciences Department, ETH Zurich, 8092 Zurich, Switzerland.
Present address: Ecole et Observatoire des Sciences de la Terre, CNRS-UMR 7516, 5 rue René Descartes, 67084 Strasbourg, France.
Present address: Alberta Geological Survey, 4999-98 Avenue, Edmonton, Alberta T6B 2X3, Canada.
||All additional authors with their affiliations appear at the end of this paper.
Project Hi-CLIMB Team
L. Mitchell,1 D. Sherstad,1 M. Arsenault,1 J. Baur,1 S. Carpenter,1 M. Donnahue,1 D. Myers,1 T.-L. Tseng,2 T. Bardell,2 N. VanHoudnos,2 M. Pandey,3 G. Chitrakar,3 S. Rajaure,3 G. Xue,4 Y. Wang,4 S. Zhou,5 X. Liang,5 G. Ye,5 C.-C. Liu,6 J. Lin,6 C.-L. Wu,6 N. Barstow7
1 College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA. 2Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL, USA. 3Department of Mines and Geology, Kathmandu, Nepal. 4Institute of Geology, Chinese Academy of Geological Sciences, Beijing, PRC. 5Institute of Theoretical and Applied Geophysics, Peking University, Beijing, PRC. 6Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan. 7PASSCAL, Socorro, NM, USA.
* To whom correspondence should be addressed. E-mail: nabelek{at}coas.oregonstate.edu
