Earthquakes and crustal deformation studies of the seismically active Kopili Fault as well as Northeast India: A scientific field study using Global Positioning System (GPS)

The North-East India is one of the seismically active regions of the world. Ithas experienced a number of great earthquakes. To know about the seismic behavior of the region, we have to study the whole region scientifically. Nowaday's Global Positioning System (GPS) is used to find out the time and velocity of tectonic plates. It gives almost perfect results upto centimeter level accuracy over a thousand kilometers of long baseline. Using GPS one can also find out the crustal deformation of fault areas. This North-East region demands a micro-seismic study to know the unknown behavior of the region. We have studied in the NNW-SSE trending Kopili Fault area in the North-East India, which is the source point of a number of earthquakes. Present day this Kopili Fault which extends from western part of Manipur upto the tri-junction of Bhutan, Arunachal Pradesh and Assam plays a great role. We have studied for the last four years (October, 2006 to February, 2011) on twelve campaign sites in this region using GPS machines and collected data for four epochs. After analysis of data, a remarkable deformation in the fault line is found which are presented in this paper.