Macroseismic survey and isoseismal map of September 2011 Sikkim earthquake

Abstract

An earthquake of M: 6.8 occurred inland at 1811 hrs (IST) on 18 September, 2011, about 68 km northwest of Gangtok, Sikkim (Latitude 27.7 ° N, Longitude 88.2° E) at a deeper depth of more than 50.0 km. Intensity survey conducted through a questionnaire and press reports were used for generation of isoseismal map using geo-statistical analysis tool of ArcGIS. Relationship between Surveyed Intensity (SI) data and Peak Ground Acceleration (PGA) was developed for the region.