| 2022年1月8日青海门源MS6.9地震前重力场动态变化 |
| |
| 引用本文： | 赵云峰, 祝意青, 隗寿春, 刘芳, 梁伟锋, 孙和平. 2023. 2022年1月8日青海门源MS6.9地震前重力场动态变化. 地球物理学报, 66(6): 2337-2351, doi: 10.6038/cjg2022Q0220 |
| |
| 作者姓名： | 赵云峰 祝意青 隗寿春 刘芳 梁伟锋 孙和平 |
| |
| 作者单位： | 1. 中国地震局第二监测中心, 西安 710054; 2. 中国科学院精密测量科学与技术创新研究院, 武汉 430071; 3. 中国科学院大学, 北京 100049 |
| |
| 基金项目： | 中国地震局地震科技星火计划项目(XH214304), 国家自然科学基金面上项目(41874092), 地震联合基金项目(U1939205), 陕西省自然科学基础研究计划(2021JQ-980)联合资助 |
| |
| 摘 要： | 2022年1月8日青海门源MS6.9地震前，中国地震局在青藏高原东北缘开展了多期流动重力观测，并观测到震中附近重力场随时间的变化.我们曾利用震中附近重力场变化信息在地震前对发震地点进行了较为准确的预测.本文综合利用地面绝对重力、相对重力资料，对青藏高原东北缘2018—2021年间的重力观测数据进行整体处理，系统分析了区域重力场动态变化及其与门源MS6.9地震发生的关系.结合地震剪切波分裂、地壳裂隙及饱和度研究成果，进一步研究了区域重力场变化的时空分布特征及其机理.结果表明：(1)门源MS6.9地震前2年累积重力变化呈现出明显的四象限分布特征，震中位于重力变化的四象限中心零等值线附近；(2)地震前重力异常持续时间与震级的关系、地震剪切波分裂产生的慢波时间延迟持续时间与震级的关系显现一致性，这种一致性表明地下流体运移可能是地震前观测到的重力变化的主要成因；(3)本次震中东南侧的显著重力变化延伸到了冷龙岭断裂东段至海原断裂一带，后期仍需要关注该地区的地震危险性.
|
| 关 键 词： | 门源MS6.9地震 中期预测 重力变化 四象限分布 流体运移 |
| 收稿时间： | 2022-04-02 |
| 修稿时间： | 2022-11-02 |
Dynamic gravity changes before the Menyuan,Qinghai MS6.9 earthquake on January 8, 2022 |
| |
| ZHAO YunFeng, ZHU YiQing, WEI ShouChun, LIU Fang, LIANG WeiFeng, SUN HePing. 2023. Dynamic gravity changes before the Menyuan, Qinghai MS6.9 earthquake on January 8, 2022. Chinese Journal of Geophysics (in Chinese), 66(6): 2337-2351, doi: 10.6038/cjg2022Q0220 |
| |
| Authors: | ZHAO YunFeng ZHU YiQing WEI ShouChun LIU Fang LIANG WeiFeng SUN HePing |
| |
| Affiliation: | 1. The Second Monitoring and Application Center, China Earthquake Administration, Xi'an 710054, China; 2. Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; 3. University of Chinese Academy of Sciences, Beijing 100049, China |
| |
| Abstract: | Before the Menyuan MS6.9 earthquake in Qinghai province on January 8, 2022, China Earthquake Administration carried out several relative gravity observations in the northeastern margin of the Qinghai-Tibet Plateau, and obtained reliable gravity data near the epicenter. We accurately predicted the location of the earthquake based on gravity changes before the Menyuan earthquake. In this study, we comprehensively processed the gravity observation data of the northeastern margin of the Tibetan Plateau from 2018 to 2021, and systematically analyzed the dynamic changes of the regional gravity field and their relationship with the occurrence of the Menyuan earthquake. Combined with the seismic shear-wave splitting results and crustal pore medium, the spatial and temporal distribution characteristics of regional gravity field variation and its mechanism are further studied. The results show that: (1) gravity change presents an obvious four-quadrant distribution in two years before the Menyuan earthquake, the epicenter is located in the center of four-quadrant and near zero isoline; (2) The relationship between the gravity anomaly duration before an earthquake and the magnitude is similar to the relationship between the slow wave time-delay caused by shear-wave splitting and the magnitude, which suggests that deep fluid migration may be the main cause of gravity variation observed before earthquake; (3) The significant gravity variation in the southeast of the epicenter extends to the east section of the Lenglongling and the Haiyuan faults, which may require more attention to the seismic hazard in this area in the further. |
| |
| Keywords: | The Menyuan MS< sub>6.9 earthquake Medium-term predication Gravity change Four-quadrant distribution Fluid migration |
|
| 点击此处可从《地球物理学报》浏览原始摘要信息 |
|
点击此处可从《地球物理学报》下载全文 |
|
