Identifying anomalous change of short line leveling on Gengda site preand afterMS8.0 Wenchuan earthquake
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摘要: 耿达短水准AB测线观测资料2006——2007年出现了累计4.59mm的张性变化,但同时段该场地A点附近进行建筑施工,这引起了该变化是否属于汶川地震前兆异常的争论.通过对耿达短水准场地现场地质和观测环境考察,在综合分析观测资料和场地内建筑施工有关信息的基础上,使用岩土力学分析程序计算施工对A点点位的影响的数值解.结果显示,建筑施工导致了约3.6mm的竖向沉降,这与同时段短水准观测的犃点点位的变化幅度相似,发展趋势一致.认为耿达短水准AB测线测值从2006——2007 年出现的变化是由于A点附近建筑施工影响所致.本文还对耿达短水准观测的2008年5月12日汶川MS8.0地震同震变化进行了分析,认为A点位于很厚的洪积扇上,当汶川地震发生时,在强烈地震动的作用下,洪积层内部空隙结构产生崩溃性破坏,从而形成地表的下沉,其沉降幅度与类似烈度条件下黄土场地的沉降幅度相当.Abstract: A total of 4.59 mm tensional change appeared in Gengda site faultcross shortline leveling route ABobservational data from 2006 to 2007, but a construction project surrounding leveling pointAwas carried out in the same period. This led an argument on whether the change is a precursory anomaly, or not, of the May 12,2008WenchuanMS8.0 earthquake. This paper introduced the field geological and environmental investigations at Gengda leveling site, and then, by using a rock and soil mechanics computation program and analyzing comprehensive observation data and construction information, we numerically calculated pointArsquo;s vertical displacement possibly induced by the construction. The calculated result shows that a subsidence of about 3.6 mm is caused by the construction progress, and its variation is similar to the leveling data change in range and trend. Therefore, we draw the conclusion that the change of Gengda leveling routeABobservational data from 2006 to 2007 is caused by the construction works near pointA .We also analyzed the coseismic change of Wenchuan earthquake observed by Gengda leveling. Because pointA is located on a very thick proluvial fan, and when the Wenchuan earthquake occurred, the internal gap structure of torrential deposit damaged by strong ground motion, as a result, the ground surface subsided, and its subsidence range is similar to the loess field under the same seismic intensity condition.
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期刊类型引用(20)
1. 张菂,李源,张伟,赵伟乔,秦忠培,郭少峰. 2023年8月西代村跨断层短水准异常分析. 地震地磁观测与研究. 2024(06): 83-91 . 百度学术
2. 王晓涛,马禾青,崔瑾,李国斌,丁风和. 汶川8.0级地震宁夏前兆异常回顾与同震响应特征分析. 地震工程学报. 2022(01): 192-202 . 百度学术
3. 荆红亮,郭国祥,靳宝萍,张聪聪,杨静,李军,韩磊. 有限差分数值模拟在跨断层资料中的应用. 山西地震. 2021(02): 32-35 . 百度学术
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5. 邵志刚,王芃. 2008年汶川8.0级地震对地震预测研究的启示思考. 地震. 2018(02): 1-10 . 百度学术
6. 郑海刚,闫伟,王雪莹,何康,李军辉,王俊. 利用不规则载荷模型分析泗县台水管异常. 华北地震科学. 2017(03): 45-48 . 百度学术
7. 李宏伟,王霞,李文超. 基于FLAC3D模拟库水位改变对周围倾斜场的影响. 山西建筑. 2016(31): 221-222 . 百度学术
8. Liu Ruichun,Jin Hongliang. Simulation by Dislocation Model and Anomaly Property Determination of Huge Leveling Deformation at Linfen Seismic Station. Earthquake Research in China. 2016(01): 100-107 . 必应学术
9. Yan Wei,Liang Libo,Niu Anfu,Chen Guoqin. Calculation of Ground Vertical Displacements, Tilts and Their Distribution Characteristics around an Irregular Load. Earthquake Research in China. 2016(02): 240-252 . 必应学术
10. 郑海刚,闫伟,王雪莹,何康,李军辉,王俊. 利用不规则载荷模型分析马家岭流动水准异常. 中国地震. 2016(03): 533-538 . 百度学术
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14. 薄万举,苏建锋,周海涛,杜雪松,万文妮,刘天海. GNSS在断层形变研究中的应用. 地震. 2014(02): 74-81 . 百度学术
15. 刘冠中,马瑾,杨永林,苏琴. 川西地区长周期气温变化对跨断层位移观测的影响及芦山地震前的异常断层活动. 地球物理学报. 2014(07): 2150-2164 . 百度学术
16. 马栋,陈建国,郑爽,李慧,王曰风. 荷载对钻孔应变观测影响的实例分析. 地震研究. 2014(01): 79-85+172 . 百度学术
17. Bo Wanju,Feng Shengtao,Su Jianfeng,Zhou Haitao,Du Xuesong,Wan Wenni,Liu Tianhai. The Application of GNSS to Fault Deformation Studies. Earthquake Research in China. 2014(04): 510-519 . 必应学术
18. 李文静,杨国华,贺建明,褚秋然,郭胜军,尹宝军. 唐山台短水准观测中复测数据特征分析. 华北地震科学. 2013(02): 67-72 . 百度学术
19. 牛安福,张凌空,闫伟,吉平. 汶川地震近震源区地形变短期前兆现象的解析. 地震. 2012(02): 52-63 . 百度学术
20. 苏琴,杨永林,向和平. 汶川8.0级地震前后鲜水河断裂带断层活动特征分析. 四川地震. 2012(01): 24-29 . 百度学术
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