【摘要】 利用青藏地区 1998～ 2 0 0 0年绝对重力和相对重力观测资料获得的区域重力场空间动态变化结果 ,初步分析了该区重力变化特征及其与监测区内 8.1级大地震的关系 .结果表明 :①昆仑山口西 8.1级大地震发生在重力负值变化高值区附近的重力变化高梯度带上 ;② 8.1级大地震前的主要构造变形与能量积累在震中的南侧 ;③主震震中以东重力负值变化高值区的范围与野外地质考察结果的破裂区域吻合得较好 ;④重力负值变化高值区的分布与GPS观测给出的应变场第二剪应变高值区一致 .更多还原

【Abstract】 The relation between the gravity variation features and M _S8.1 earthquake in Qinghai-Tibet monitoring area is analyzed preliminarily, by using spatial dynamic variation results of regional gravity field from absolute gravity and relative gravity observation in 1998 and 2000. The results show that: ① M _S8.1 earthquake in Kunlun mountain pass western occurred in the gravity variation high gradient near gravity′s high negative variation; ② The main tectonic deformation and energy accumulation before M _S8.1 earthquake are distributed at south side of the epicenter;③ The range of gravity′s high negative variation at east of the M _S8.1 earthquake epicenter relatively coincides with that rupture region according to field geology investigation; ④ Gravity variation distribution in high negative value region is just consistent with the second shear strain′s high value region of strain field obtained from GPS observation.更多还原