Evidence for a Great Medieval Earthquake (
1100 A.D.) in the Central Himalayas, Nepal
J. Lavé,1*
D. Yule,2*
S. Sapkota,3
K. Basant,3
C. Madden,4
M. Attal,1
R. Pandey3
The Himalayan orogen has produced three thrust earthquakes with moment magnitude (Mw) 7.8 to 8.5 during the past century, yet no surface ruptures associated with these great earthquakes have been documented. Here, we present paleoseismic evidence from east central Nepal that, since
700 A.D., a single earthquake ruptured the Frontal Thrust fault at
1100 A.D., with a surface displacement of
17 (+5/3) meters and a lateral extent and size that could have exceeded 240 kilometers and
Mw 8.8, respectively. Ruptures associated with Mw <8.2 events would contribute to the frontal Himalayas folding but would stop before reaching the surface. These findings could require substantial modifications to current regional seismic hazard models.
1 Laboratoire de Géodynamique des Chaînes Alpines, BP53, 38041 Grenoble, France.
2 California State University, Northridge, CA 91330, USA.
3 Seismolab, Department of Mines and Geology, Lainchaur, Kathmandu, Nepal.
4 Earth Consultants International, Tustin, CA 92780, USA.
* These authors contributed equally to this work.
To whom correspondence should be addressed. E-mail: jlave{at}ujf-grenoble.fr