利用GRACE卫星测量数据,以3个月时间尺度计算了2011-07—09月印度地震区域的重力场变化,并将计算结果与2009年和2010年同一时间尺度的变化结果进行比较,结果显示,2009年研究区域的重力值变化为正,其中新德里、博帕尔、锡金邦地区重力变化均超过了4×10-8ms-2,表明此段时期内地壳应力处于积累状态,2010年同期重力变化较小,2011年地震区域重力变化较大,震中重力值较2009年变化了约6×10-8ms-2。强震就发生在重力变化梯度带内。
The gravity variations were computed in Indian earthquake region (76° -96°E, 16° -36°N) with GRACE data observed from July to September in 2009,2010 and 2011 respectively taking the GRACE GGM03C gravity field model as a reference and then the monthly gravity variations of Indian mainland before and after the Gaussian smoothing were compared between each other. The computed result is the most reasonable when the radius of the Gaussian smoothing is 600 kin. The results show that the gravity variation of the studied area was positive in 2009. The gravity variation changed more than 4 × 10^-8 ms^-2 in New Delhi, Bhopal and Sikkim districts. In 2010, it was smaller than that in the same time ,2009. The gravity variation change at the epicenter was of almost 6 × 10^ -8 ms^-2 in 2011 than that in 2009. The strong earthquake occurred within the steep gradient zone.