Influence of anthropogenic groundwater unloading in Indo‐Gangetic plains on the 25 April 2015 Mw 7.8 Gorkha, Nepal earthquake. Issue 24 (23rd December 2015)

• Record Type: Journal Article
• Authors: Kundu, Bhaskar; Vissa, Naresh Krishna; Gahalaut, V. K.
• Is Part Of: Geophysical research letters. Volume 42:Issue 24(2015:Dec.)
• Page Start: 10, 607
• Page End: 10, 613
• Publication Date: 2015-12-23
• Subjects: 2015 Gorkha, Nepal earthquake -- Indo‐Gangetic plains -- groundwater -- Nepal Himalaya -- Coulomb stress -- Main Himalayan Thrust; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL066616
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Groundwater usage in the Indo‐Gangetic plains exceeds replenishment of aquifers, leading to substantial reduction in the mass. Such anthropogenic crustal unloading may promote long‐term fault slip or may modulate seismic activity in the adjoining Himalayan region. Our simulation using Gravity Recovery and Climate Experiment data and hydrological models of such a process indicates that the thrust earthquakes on the Main Himalayan Thrust (MHT), including the recent 25 April 2015 Mw 7.8 Gorkha, Nepal earthquake, are probably influenced by the anthropogenic groundwater unloading process in the Gangetic plains. The groundwater withdrawal leading to crustal unloading in the Gangetic plains causes a significant component of horizontal compression which adds to the secular interseimic compression at the seismogenic depth (5–20 km) on the MHT beneath the Himalayan arc and at hypocentral depth of the 2015 Gorkha, Nepal earthquake. This effect enhances the Coulomb stress on the locked zone of MHT. Key Points: Groundwater withdrawal leading to crustal unloading in the Indo‐Gangetic plains It enhances the Coulomb stress on the locked zone of MHT The 2015 Gorkha, Nepal earthquake is influenced by anthropogenic unloading