A comparative study of gravity and crustal deformation data through superconducting gravimeter and GPS observations in the North-West Himalayan region

Abstract

Simultaneous observations of gravity measurements and vertical crustal deformation are carried out at the Multi-Parametric Geophysical Observatory (MPGO), Ghuttu (Location 30.53 o N, 78.74 o E) located in Northwestern part of Himalaya in India. The temporal variation of gravity measurements are monitored by a superconducting gravimeter while the crustal deformations are observed using a dual frequency GPS antenna and receiver system. The simultaneous data collected by both instruments during a period of ~3 years from 2007 to 2010 is evaluated. Both data sets show apparent seasonal/annual changes with a clear phase difference of few months causing negative correlation between the two time series. Loading effects on the Earth's uppermost crust due to the hydrological cycle, as measured from local water table record, are advocated as the explanation of the observed seasonal variation.

Diurnal pressure variations in the Garhwal Himalaya: atmospheric fluctuations associated with the solid Earth tide

“…The pressure and gravity data collected at Kopardhar are recorded at 1‐s intervals re‐sampled at 15‐min intervals. A continuous temporal series of gravitational data can be obtained using a superconducting gravimeter (Chauhan et al ., ). This high‐precision instrument is capable of recording gravity variations at the μgal level (1 microgal = 10nms −2 ), which is suitable for detecting solid Earth tides (Merriam, ).…”

“…The results are compared with solid tides observed in gravity data at the same site. High resolution gravity measurements were obtained at 1‐s intervals using a superconducting gravimeter manufactured by GWR Instruments, San Diego, CA, USA (Arora et al ., ; Chauhan et al ., ).…”