王向腾^1,2,,
李志伟^3,,,
邓居智¹,
高金哲⁴,
李红星¹,
姚振岸¹,
李晶晶¹
1. 东华理工大学核资源与环境国家重点实验室, 南昌 330013
2. 中国科学院精密测量科学与技术创新研究院大地测量与地球动力学国家重点实验室, 武汉 430077
3. 北京卫星环境工程研究所, 可靠性与环境工程技术重点实验室, 北京 100094
4. 吉林省地震局, 长春 130117

基金项目: 国家自然科学基金（41804044，42004040，41674077），核资源与环境国家重点实验室开放基金（NRE1920），大地测量与地球动力学国家基金（SKLGED2020-4-1-E）以及国家重点研发计划（2018YFC1504202）联合资助


详细信息

作者简介: 王向腾, 男, 东华理工大学地球物理与测控技术学院讲师, 主要从事地震定位与震源参数研究.E-mail: wangxt@whigg.ac.cn

通讯作者: 李志伟, 男, 研究员, 主要从事地震学研究.E-mail: zwli@whigg.ac.cn

中图分类号: P315

收稿日期:2020-06-28
修回日期:2020-12-14
上线日期:2021-03-10

Hypocentral depth determination for moderate-magnitude shallow earthquakes in sedimentary basins with sparse network——case studies of the 2013 Qainguo M_S5.8 and the 2016 Fairview M_W5.1 earthquake sequences

WANG XiangTeng^1,2,,
LI ZhiWei^3,,,
DENG JuZhi¹,
GAO JinZhe⁴,
LI HongXing¹,
YAO ZhenAn¹,
LI JingJing¹
1. State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China
2. State Key Laboratory of Geodesy and Earth's Dynamics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430077, China
3. Beijing Institute of Spacecraft Environment Engineering, Beijing 100094, China
4. Jilin Earthquake Agency, China Earthquake Administration, Changchun 130117, China


More Information

Corresponding author: LI ZhiWei,E-mail:zwli@whigg.ac.cn

MSC: P315

--> Received Date: 28 June 2020
Revised Date: 14 December 2020
Available Online: 10 March 2021


摘要
摘要:沉积盆地中的中等强度浅源地震起始深度不仅是地震成灾研究的重要参数，还是深地下工程开采诱发地震成因研究的关键信息.然而在台网稀疏、沉积层结构复杂的盆地地区，仅利用直达波到时，常常难以获得较为准确的地震起始深度.基于参考事件的Pn/Pg相对定位方法加入Pn震相，可以有效提高震源深度的测定精度.本文针对松辽盆地中2013年前郭M_S5.8地震序列以及Oklahoma州2016年Fairview M_W5.1地震序列，利用Pn/Pg方法测定了两个地震序列中较大地震的起始破裂深度.结果显示：在2013年前郭地震序列中，两个较大地震起始深度和质心深度均在3~5 km左右，震源机制中含有较大的非双力偶源成分.而2016年Fairview M_W5.1地震，主震起始深度约7 km，质心深度约8 km，5个较大的前震则深度分布在5~9 km.根据上述测定结果，推测2013年11月前郭M_S5.8地震序列可能与震源附近的注水活动有关，而2016年Fairview M_W5.1地震则可能由较远处注水活动触发.
关键词: 浅源地震/
台网稀疏/
起始深度/
沉积盆地

Abstract:The hypocentral depth of moderate-magnitude shallow earthquakes in sedimentary basins is not only an important parameter in the study of earthquake disaster but also provides important information for the mechanism study of induced-earthquake by deep fluid-injection. However, in sparse network areas with thick sediments, it is difficult to obtain a more accurate hypocentral depth by using only direct waves. Based on reference events, Pn/Pg method combined Pg and Pn phases to improve the accuracy of the hypocentral depth. For the 2013 Qainguo M_S5.8 sequence in the Songliao Basin and the 2016 Fairview M_W5.1 earthquake sequence in Oklahoma, this study utilizes the Pn/Pg method to determine the hypocentral depth of the larger earthquakes in the two earthquake sequences. The results suggest that for the 2013 QianGuo earthquake sequence, the hypocentral depths and the centroid depths of two larger earthquakes were both around 3~5 km, and the focal mechanism contained a large non-double-couple component. For the 2016 Fairview M_W5.1 sequence, the hypocentral depth of the mainshock was about 7 km, the centroid depth was about 8 km, and the five larger foreshocks were distributed at 5~9 km. Based on the results, we inferred that the 2013 Qianguo M_S5.8 earthquake sequence may be related to the nearby fluid injection activities. The 2016 Fairview M_W5.1 earthquake may be induced by pressure disturbances caused by water injection nearby, which should cause the fault reactivity.
Key words:Shallow earthquakes/
Sparse seismic network/
Hypocentral depth/
Sedimentary basins



PDF全文下载地址:

http://www.geophy.cn/data/article/export-pdf?id=608009f8c23e67607ae103db