Seismicity study in relation to recent earthquakes in Jammu and adjoining Himachal Pradesh

Abstract

Seismicity variations associated with four recent earthquakes in eastern Kashmir and adjoining Himachal Pradesh have been studied with the help of closely spaced seismological network in the region. It was noticed that earthquakes of August 1980 in Bhaddu and Malar regions of Jammu province and two other earthquakes (1973, 1976) in adjoining western Himachal Pradesh occurred in a region of low seismic activity. These earthquakes of magnitude 4 to 5 were preceded by anomalous seismic activity with the precursory duration ranging from 3 to 7 years. Fault plane solutions of two earthquakes of 23 August 1980 (21 h 36 m 52.3 s) and 7 January 1976 show thrust fault and are associated with the main-boundary fault in the region. However, the second earthquake of 23 August 1980 ( 21 h 50 m 02.90 s) appears to be associated with Surin-Mustgarh anticline.