Abstract Views :195 |
PDF Views:2
Authors
Affiliations
1 Earthquake Geology Division, Geological Survey of India, Eastern Region, DK-Block, Sector-II, Salt Lake City, Kolkata - 700 095, IN
2 Earthquake Geology Division, Map Division, Geological Survey of India, Eastern Region, DK-Block, Sector-II, Salt Lake City, Kolkata - 700 095, IN
3 Earthquake Geology Division, TC-1 Division, Geological Survey of India, Eastern Region, DK-Block, Sector-II, Salt Lake City, Kolkata -
700 095, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 71, No 4 (2008), Pagination: 541-550
Abstract
A moderate earthquake struck the Sikkim Himalaya on Tuesday, February 14, 2006 at 6.25 am. The earthquake was felt in North Bengal, Sikkim,nepal and Bhutan. Macroseismic survey was carried out for the accessible regions of Sikkim and the northern portion of West Bengal to assesses the intensity of ground motion, the damage caused by the earthquake and also to ascertain the possible source and its orientation.
The survey results show that the MSK (Medvedev-Sponheuer-Karnik) intensity varies between III to VII. The maximum intensity is found in Gangtok-Deorali-Tadonga areas, which are far from the instrumental epicenters identified by USGS and IMD. Statistical procedure has been adopted for numerical weighted intensity calculation to quantify the MSK intensity and for deducing the isoseismal lines more logically. Separate macroseismc epicenter is calculated from the high MSK- intensity sites, which falls in between Deoralt and Tadong. The probable orientation of the source (fault) is found to be E-W that passes through Makha village, north of Gangtok area. The damages to constructions on the terraces is much less than those constructed on other topographic forms, like slopes, ridges and low zones. Within the most damaged Gangtok-Deorail Tadong areas, most of the buildings are located along the ridge top or along the ridge axis.
Keywords
Earthquake, Macroseismic Survey, Sikkim.
