Faulting structure above the Main Himalayan Thrust as shown by relocated aftershocks of the 2015M_w7.8 Gorkha, Nepal, earthquake (original) (raw)

2016, Geophysical Research Letters

The 25 April 2015, M w 7.8 Gorkha, Nepal, earthquake ruptured a shallow section of the Indian-Eurasian plate boundary by reverse faulting with NNE-SSW compression, consistent with the direction of current Indian-Eurasian continental collision. The Gorkha main shock and aftershocks were recorded by permanent global and regional arrays and by a temporary local broadband array near the China-Nepal border deployed prior to the Gorkha main shock. We relocate 272 earthquakes with M w > 3.5 by applying a multiscale double-difference earthquake relocation technique to arrival times of direct and depth phases recorded globally and locally. We determine a well-constrained depth of 18.5 km for the main shock hypocenter which places it on the Main Himalayan Thrust (MHT). Many of the aftershocks at shallower depths illuminate faulting structure in the hanging wall with dip angles that are steeper than the MHT. This system of thrust faults of the Lesser Himalaya may accommodate most of the elastic strain of the Himalayan orogeny. The MHT is defined as the detachment that separates the underthrusting Indian plate from the overriding Himalaya orogeny. The concept of the MHT was proposed by Ni and Barazangi [1984] based on the locations RESEARCH LETTER

Sign up for access to the world's latest research.

checkGet notified about relevant papers

checkSave papers to use in your research

checkJoin the discussion with peers

checkTrack your impact