地球物理学报
地毬物理學報
지구물이학보
2009年
10期
2538-2546
,共9页
祝意青%徐云马%吕弋培%李铁明
祝意青%徐雲馬%呂弋培%李鐵明
축의청%서운마%려익배%리철명
龙门山断裂带%汶川地震%重力异常%地壳运动%构造活动
龍門山斷裂帶%汶川地震%重力異常%地殼運動%構造活動
룡문산단렬대%문천지진%중력이상%지각운동%구조활동
Longmenshan fault zone%Wenchuan M_S8. 0 earthquake%Gravity anomaly%Crust movement%Tectonic movement
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~(-8)m·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.
利用成都地區1996~2008年絕對重力和相對重力觀測資料穫得區域重力場時空動態變化結果,繫統分析瞭龍門山斷裂帶重力場變化特徵及其與汶川8.0級地震的關繫.①重力變化與龍門山斷裂構造活動存在密切空間聯繫,重力測量較好地反映瞭伴隨活動斷層的物質遷移和構造變形引起的地錶重力變化效應.②成都地區重力場動態圖像較完整地反映瞭2008年5月12日汶川8.0級地震孕育、髮生過程中齣現的流動重力前兆信息.③映秀及北川重力點值時序變化纍積量達120×10~(-8)m·s~(-2),較好地反映瞭汶川地震前映秀和北川兩箇極震區附近的重力測點隨時間的劇烈波動性上升變化.④汶川地震前,龍門山斷裂帶東側的四川盆地相對穩定,而較顯著的重力變化髮生在龍門山斷裂帶西側的川西高原上.
이용성도지구1996~2008년절대중력화상대중력관측자료획득구역중력장시공동태변화결과,계통분석료룡문산단렬대중력장변화특정급기여문천8.0급지진적관계.①중력변화여룡문산단렬구조활동존재밀절공간련계,중력측량교호지반영료반수활동단층적물질천이화구조변형인기적지표중력변화효응.②성도지구중력장동태도상교완정지반영료2008년5월12일문천8.0급지진잉육、발생과정중출현적류동중력전조신식.③영수급북천중력점치시서변화루적량체120×10~(-8)m·s~(-2),교호지반영료문천지진전영수화북천량개겁진구부근적중력측점수시간적극렬파동성상승변화.④문천지진전,룡문산단렬대동측적사천분지상대은정,이교현저적중력변화발생재룡문산단렬대서측적천서고원상.
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_S8. 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. ②The 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_s8. 0 earthquake. ③The temporal changes' value of gravity point (Yingxiu, Beichuan) cumulate to 120×10~(-8)m·s~(-2) shows that gravity field near meizoseismal region have fast increased after the Wenchuan M_S8. 0 earthquake. ④Before 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.