摘要
提取豫鄂皖交界区震源机制、钻孔应变YRY、洞体应变SSY和跨断层水准等数据中蕴含的断裂运动信息,经三维应力分析,发现:①NW向青山—晓天断裂和金寨—龙河口断裂以左行走滑运动为主,而NE向落儿岭—土地岭断裂和商城—麻城断裂呈明显的右行走滑运动,断裂的三维应力状态描述为σ_(1)和σ_(3)是水平的,σ_(2)是直立的,基本延续了中、晚更新世时期断裂的运动状态;②NW向金寨—龙河口断裂和青山—晓天断裂具有逆倾向挤压应变背景,而NE向落儿岭—土地岭断裂和商城—麻城断裂呈明显的正倾向拉张的应变特征。掌握这些断裂的二维运动特征,可为进一步推断断裂三维特征提供研究基础。
This paper extracts fault movement information in the border area of Henan,Hubei and Anhui provinces from focal mechanism solutions,borehole strain YRY observations,cavity strain SSY observations,and cross-fault measurement.Three-dimensional stress analysis shows:①The northwest oriented Qingshan-Xiaotian fault and Jinzhai-Longhekou fault are dominated by left-slip movement and the north-east oriented Luoerling-Tudiling fault and Shangcheng-Macheng fault show obvious right-slip movement.The three-dimensional stress state of the ruptures is described as thatσ_(1) andσ_(3) are horizontal andσ_(2) is vertical.The fault movement pattern in the middle and late Pleistocene was basically continued;②The north-west oriented Qingshan-Xiaotian fault and Jinzhai-Longhekou fault show a compressive strain background against the dip direction and the north-east Luoerling-Tudiling fault and Shangcheng-Macheng fault show obvious stretch strain characteristics with dip direction.Understanding the two-dimensional motion characteristics of these faults provides a research basis for further inferring their three-dimensional motion characteristics.
作者
余尚江
卢亚
陈贤
YU Shangjiang;LU Ya;CHEN Xian(Henan Earthquake Agency,Zhengzhou 450016,China)
出处
《地震地磁观测与研究》
2021年第3期74-83,共10页
Seismological and Geomagnetic Observation and Research
基金
中国地震局监测、预报、科研三结合课题(项目编号:CEAJC/3JH-202001062)。
关键词
豫鄂皖交界区
震源机制
场地应变
跨断层水准
断裂运动特征
border area of Henan
Hubei and Anhui provinces
earthquake focal mechanism
field strain
cross-fault measurement
fault motion characteristics
