Revalidation Of Indian Plate Kinematics With Recent Plate Velocities From GPS-Geodesy

Already estimated Indian Plate motion at the rate of 37 \pm 0.2 mmyr^-1 towards NNE direction with respect to Eurasian Plate has been revalidated with a new global network spreading the geographical and azimuthal coverage, which almost includes all the plates surrounding India. 8 years of GPS data from September 1995 to mid 2003 from the Hyderabad IGS GPS Permanent Station (HYDE) have been processed in the global network solution along with the data from other 8 stations. The baseline lengths from Hyderabad to other chosen sites and the rate of changes were also estimated. The angular velocity of Indian plate motion with respect to ITRF-97 reference frame and Indo-Eurasia plate pair have also been estimated. The global network solution has resulted in the estimation of the pole of the angular velocity vector of India with respect to Eurasia to be about a pole of rotation at 29.44 \pm 1.2\deg N, 13.2 \pm 7.3\deg E with an angular velocity of 0.356 \pm 0.035\deg Myr ^-1. Our results mostly conform to the REVEL-2000 Plate motion model but differs considerably from NUVEL-1A and other earlier studies. This departure could be attributed to the difference in geologic and geodetic estimations. The longer time span of GPS data from the central part of India yields more accurate estimations and the analysis is in the global network solution, which doesn't take into account the plate- interior site velocities if at all there are any differences from the plate velocities. The estimated strain accumulation in the south of Indian peninsula shows an increase in the elastic strain accumulation at the rate of 1.27x10^-8yr^-1.