【摘要】 利用成都地区1996-2008年绝对重力和相对重力观测资料获得区域重力场时空动态变化结果,系统分析了龙门山断裂带重力场变化特征及其与汶川8.0级地震的关系.①重力变化与龙门山断裂构造活动存在密切空间联系,重力测量较好地反映了伴随活动断层的物质迁移和构造变形引起的地表重力变化效应.②成都地区重力场动态图像较完整地反映了2008年5月12日汶川8.0级地震孕育、发生过程中出现的流动重力前兆信息.③映秀及北川重力点值时序变化累积量达120×10^-8m·s^-2,较好地反映了汶川地震前映秀和北川两个极震区附近的重力测点随时间的剧烈波动性上升变化.④汶川地震前,龙门山断裂带东侧的四川盆地相对稳定,而较显著的重力变化发生在龙门山断裂带西侧的川西高原上.更多还原

【Abstract】 The observed results of repeated absolute and relative gravity measurements in Chengdu arear during 1996 - 2008 are systemically analyzed, and then discuss the relationship between gravity variation of Longmenshan fault zone and Wenchuan M_S 8. 0 earthquake. The results show as follows. ①The change of gravity field is closely relative to tectonic movement of Longmenshan fault zone. The change of surface gravity field caused by the active faults associated with the mass transfer and structural deformation can be effectively reflect by gravity measurements.② The dynamic images of gravity field in Chengdu arear base on absolute gravity measurements can express the precursory gravity information during the seismogenic process of the Wenchuan M_S 8. 0 earthquake.③The temporal changes’ value of gravity point （Yingxiu, Beichuan） cumulate to 120 ×10^-8m • s^-2 shows that gravity field near meizoseismal region have fast increased after the Wenchuan M_S 8. 0 earthquake. ©Before Wenchuan earthquake, the gravity anomaly in the Sichuan Basin on the east side of Longmenshan fault zone is relative stability, and the gravity anomaly in the West Sichuan Plateau on the west side of Longmenshan fault zone is significant changes.更多还原