A Brief Report on Impacts and Implications of 2011 Sikkim (India-Nepal Border Region) Earthquake

This is a brief report on the impacts and implications of 2011 Sikkim (India-Nepal Border Region) earthquake.

The M6.9 Sikkim earthquake of September 18, 2011 struck at 18:10:48 IST lasted about 30 to 40 seconds with its epicenter located at 27.72°N, 88.06°E near India-Nepal border region, about 68 km NW of Gangtok at a focal depth of 19.7 km. Three aftershocks of magnitude 5.7, 5.1 and 4.6 were also felt in Sikkim within 30 minutes of the initial earthquake. This region has experienced relatively moderate seismicity, with 18 earthquakes of M5 or greater over the past 35 years within 100 km of the epicenter of the September 18, 2011 event. The affected region lies in the high risk seismic zones of IV of Indian seismic code IS:1893 with the expected shaking intensity of VIII (on MSK scale).