汶川Ms8.0地震前渭河盆地的断层活动特征分析  

ANALYSIS ON ACTIVITY CHARACTERISTICS OF FAULTS IN WEIHE BASIN BEFORE WENCHUAN Ms8.0 EARTHQUAKE

作　　者：曹建平[1] 张永奇[1] 郑增记 韩美涛[1] 冯希杰[1] 石军[1] CAO Jianping;ZHANG Yongqi;ZHENG Zengji;HAN Meitao;FENG Xijie;SHI Jun(Shanxi Earthquake Agency, Xi’an 710068, China)

机构地区：[1]陕西省地震局,陕西西安710068

出　　处：《高原地震》2020年第1期8-13,共6页Plateau Earthquake Research

基　　金：陕西省地震局启创基金(项目编号:QC201602,QC201717);中国地震局“三结合”课题(项目编号:3JH-201902006)联合资助。

摘　　要：本文对汶川地震前渭河盆地跨断层水准资料进行了回顾性分析,结果表明:(1)震前鄂尔多斯块体西南缘—南缘—东南缘与渭河盆地交界处的断裂带活动及渭河盆地内部近北东向的断裂带活动出现了远场形变异常;(2)北西向岐山—马召断裂带上的南大同场地处断裂带活动也出现了远场形变异常,可能与其位于汶川地震的烈度Ⅵ度影响区有关;(3)渭河盆地内近东西走向的断裂带活动基本上没有出现异常变化;(4)震前异常持续时间约在4个月~2年之间。In this paper,the cross-fault leveling data of weihe basin before wenchuan earthquake were analyzed retrospectively,and the results showed that:(1)Before the Wenchuan earthquake,the far-field deformation anomalies appeared in the fault zone activity at the junction of the southwest margin-south margin-southeast margin of the Ordos block and Weihe basin,at the same time,the northeast direction fault activity inside the Weihe basin has appeared far-field deformation anomalies.(2)The fault activities of Nandatong field which located at the northwest Qishan-Mazhao fault have appeared far field deformation anomaly,it is may be related to its location in the magnitudeⅥimpact zone of the Wenchuan earthquake.(3)There are no abnormal changes of the east-west fault activity in Weihe basin.(4)The abnormal duration of fault activity before the Wenchuan earthquake is about 4 months to 2 years.

关 键 词：汶川MS8.0地震 渭河盆地 活动断裂 跨断层形变 异常特征 

分 类 号：P315.725[天文地球—地震学]