地震学报
地震學報
지진학보
ACTA SEISMOLOGICA SINICA
2010年
1期
23-32
,共10页
GPS%地震复发间隔%应变率%地震矩率%川滇地区
GPS%地震複髮間隔%應變率%地震矩率%川滇地區
GPS%지진복발간격%응변솔%지진구솔%천전지구
GPS%earthquake recurrence interval%strain rate%seismic moment rate%Sichuan-Yunnan region
利用川滇南部GPS站点速度资料,采用Kriging插值和有限单元中形函数(拉格朗日差值函数)求导原则,计算了川滇南部主应变速率.在此基础上,引入Kostrov地震矩率计算方法,由主应变速率求得了研究区的地震矩率,进而借助于Ward地震平均复发间隔公式计算了研究区地震(M_S≥6.5)平均复发间隔.计算结果表明,川滇南部不同震级档地震复发间隔空间分布总体上与区内主要活动断裂展布基本吻合; 地震复发间隔低值区主要分布在地震活动水平和滑动速率较高的安宁河-则木河-小江断裂带、丽江-小金河断裂西南段、红河断裂西北段.所得的结果与利用历史地震资料获得的结果基本一致.该方法对于历史地震资料缺乏或不完整地区和活动断层定量研究程度较低的地区有着潜在的应用价值.
利用川滇南部GPS站點速度資料,採用Kriging插值和有限單元中形函數(拉格朗日差值函數)求導原則,計算瞭川滇南部主應變速率.在此基礎上,引入Kostrov地震矩率計算方法,由主應變速率求得瞭研究區的地震矩率,進而藉助于Ward地震平均複髮間隔公式計算瞭研究區地震(M_S≥6.5)平均複髮間隔.計算結果錶明,川滇南部不同震級檔地震複髮間隔空間分佈總體上與區內主要活動斷裂展佈基本吻閤; 地震複髮間隔低值區主要分佈在地震活動水平和滑動速率較高的安寧河-則木河-小江斷裂帶、麗江-小金河斷裂西南段、紅河斷裂西北段.所得的結果與利用歷史地震資料穫得的結果基本一緻.該方法對于歷史地震資料缺乏或不完整地區和活動斷層定量研究程度較低的地區有著潛在的應用價值.
이용천전남부GPS참점속도자료,채용Kriging삽치화유한단원중형함수(랍격랑일차치함수)구도원칙,계산료천전남부주응변속솔.재차기출상,인입Kostrov지진구솔계산방법,유주응변속솔구득료연구구적지진구솔,진이차조우Ward지진평균복발간격공식계산료연구구지진(M_S≥6.5)평균복발간격.계산결과표명,천전남부불동진급당지진복발간격공간분포총체상여구내주요활동단렬전포기본문합; 지진복발간격저치구주요분포재지진활동수평화활동속솔교고적안저하-칙목하-소강단렬대、려강-소금하단렬서남단、홍하단렬서북단.소득적결과여이용역사지진자료획득적결과기본일치.해방법대우역사지진자료결핍혹불완정지구화활동단층정량연구정도교저적지구유착잠재적응용개치.
With a combination of the Kriging interpolation and shape function's derivative (Lagrange interpolation function) used in finite element analysis, we have derived the elastic strain rate field in southern Sichuan-Yunnan region, China, based on the regional GPS velocity observations. Furthermore, the derived strain rate is directly converted into the seismic moment rate according to the Kostrov's moment rate formula. By means of the Ward's recurrence interval formula the recurrence intervals of M_S≥6.5 earthquakes in southern Sichuan-Yunnan region are obtained numerically. The result shows that the contours of earthquake recurrence intervals generally coinside with the major fault zones. The low interval values are on the Anninghe-Zemuhe-Xiaojiang fault, the southwestern Lijiang-Xiaojinhe fault and the northwestern Red River fault, where the level of fault slip rate and earthquake activity is high. In general, the average earthquake recurrence intervals estimated in this paper are comparable with the intervals obtained from historical earthquake investigations. It should be pointed out that the methodology described in this paper has potential of application in modern seismic hazard assessment, especially for the regions being lack of instrumental and historical records.