欢迎访问《地震》,

地震 ›› 2025, Vol. 45 ›› Issue (2): 115-131.doi: 10.12196/j.issn.1000-3274.2025.02.008

• • 上一篇    下一篇

2020年河北唐山M5.1地震前地下流体典型异常特征分析

孙宇飞1,2, 任佳1,2, 张帆1,2, 张凤秋1,2, 只楠1,2, 姜佳宁1,2   

  1. 1.河北红山巨厚沉积与地震灾害国家野外科学观测研究站, 河北 邢台 055350;
    2.张家口地震监测中心站, 河北 张家口 075000
  • 收稿日期:2024-04-23 接受日期:2024-06-24 发布日期:2025-09-05
  • 通讯作者: 任佳, 高级工程师。 E-mail: 381201241@qq.com
  • 作者简介:孙宇飞(1996-), 男, 河北承德人, 助理工程师, 主要从事地下流体观测研究。 E-mail: 364926079@qq.com
  • 基金资助:
    中国地震局地震科技星火攻关项目(XH24002B); 河北地震科技星火计划攻关项目 (DZ2024112200010, DZ2024112200009); 河北地震科技星火计划青年项目 (DZ2024112500009)

The Typical Anomaly Characteristics of the Underground Fluid before the 2020 Tangshan M5.1 Earthquake

SUN Yu-fei1,2, REN Jia1,2, ZHANG Fan1,2, ZHANG Feng-qiu1,2, ZHI Nan1,2, JIANG Jia-ning1,2   

  1. 1. Hebei Hongshan National Observatory on Thick Sediments and Seismic Hazards, Shijiazhuang 050021, China;
    2. Zhangjiakou Earthquake Monitoring Center Station, Zhangjiakou 075000, China
  • Received:2024-04-23 Accepted:2024-06-24 Published:2025-09-05

摘要: 地震地下流体异常在地震预报及区域危险性判定中起着重要作用。 对2020年7月12日唐山M5.1地震震中附近地下流体异常进行了分析和总结。 结果表明, 震前河北、 天津地区距离震中250 km范围内有8项地下流体前兆异常, 典型异常可分为两类: 一种是水位异常, 另一种是水温异常。 异常时间以1~6个月为主; 异常出现时间与震中距间的关系不明显; 异常形态与以往震例异常形态较为一致, 具有明显的重复性; 从空间位置来看, 异常主要分布在震中100 km范围内, 主要沿着北东向唐山断裂带分布。 震源机制解结果显示, 此次地震的发震断层走向为235°, 倾角为76°, 滑动角为-173°, 震源深度为14 km, 震源机制解所得主压应力作用方向与地震前流体异常展布方向相同。 说明此次地下流体异常不只是地震震源体活动导致的, 而是华北地区北东向构造应力变化的结果, 受构造活动控制的影响。 研究结果有利于识别与构造活动有关地震地下流体前兆异常变化, 为震情跟踪提供参考依据。

关键词: 河北唐山M5.1地震, 地下流体, 典型异常, 特征分析

Abstract: Earthquake underground fluid anomalies play an important role in earthquake prediction and regional risk evaluation. This paper analyzes and summarizes the underground fluid anomalies near the epicenter of Tangshan M5.1 earthquake on July 12, 2020. The results show that: Before the earthquake, there were 8 underground fluid precursor anomalies within 250 km from the epicenter in Hebei and Tianjin. Typical anomalies can be divided into two categories, one is water level anomaly and the other is water temperature anomaly. The abnormal time is mainly 1~6 months. The relationship between the occurrence time of anomaly and the epicenter distance is not obvious. The abnormal shape is consistent with that of previous earthquake cases and has obvious repeatability. From the perspective of spatial location, the anomaly is mainly distributed within 100 km of the epicenter, and the anomaly is mainly distributed along the Tangshan fault zone in the northeast direction. The results of source mechanism solution show that the strike of the seismic fault is 235°, the dip angle is 76°, the slip angle is -173°, and the focal depth is 14 km. The direction of compressive stress induced by source mechanism solution is the same as that of fluid anomaly distribution before the earthquake. It shows that the underground fluid anomaly is not only caused by the activity of seismic source body, but also results from the change of tectonic stress in northeast direction in North China, which is influenced by the control of tectonic activity. The research results are helpful in identifying the abnormal changes of underground fluid precursor related to tectonic activity and provide reference for earthquake tracking.

Key words: Tangshan, Hebei Province M5.1 earthquake, Underground fluid, Typical anomaly, Feature analysis

中图分类号: