Stress shadow, stress triggering, and recent earthquake activity in the Kashmir Himalaya, India

• Published in: Journal of seismology 2022-02, Vol.26 (1), p.167-179
• Main Authors: Prasath, R. Arun, Verma, Mithila, Bansal, Brijesh K.
• Format: Article
• Language: English
• Subjects: Analysis; Earth and Environmental Science; Earth Sciences; Earthquake data; Earthquakes; Energy budget; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Hydrogeology; Original Article; Seismic activity; Seismicity; Seismology; Sequencing; Shadows; Slip; Stress analysis; Stress transfer; Structural Geology
• ISSN: 1383-4649; 1573-157X
• DOI: 10.1007/s10950-021-10067-4

The Kishtwar-Chamba-Zanskar Region in Kashmir Himalaya show increased earthquake activity during last few years, especially, after the 2013 earthquake sequence in Kishtwar area that includes the 2013 Kishtwar earthquake ( M W 5.6). More recently, a similar sequence (2019–2020) has been recorded in the east (Zanskar) and southeast (Chamba) of Kishtwar area. We evaluate the present seismicity scenario of Kishtwar-Chamba-Zanskar Region, which involves spatio-temporal analysis, energy budget, slip-deficit, and coulomb stress transfer, using a homogenized earthquake catalog for the period from 1965 to July 2020. The analysis suggests that 2013 sequence occurred after a quiescence period of ~ 23 years, i.e., from 1991 to April 2013 and the study region was under stress shadow, possibly created by the 1991 Uttarkashi earthquake ( M W 6.8). Further, the recent seismic activity since 2013, mark the beginning of new earthquake cycle with frequent moderate earthquakes. The coulomb stress analysis further suggests that stress transfer due to 2013 Kishtwar earthquake ( M W 5.6) may have triggered the recent earthquake activity in the region, including 2019–2020 sequence. The energy budget and slip deficit calculated using the earthquake data of more than five decades, indicate that the region has the potential for a large earthquake of M W  ~ 7.0.