辽宁灯塔地震前地下流体、形变异常时空演化特征及成因  

Temporal and Spatial Evolution Characteristics and Genesis of Underground Fluid and Deformation Anomalies Before the Liaoning Dengta Earthquake

作　　者：王海燕[1] 俢常耀 钱蕊[1] 黄明威 刘硕 WANG Haiyan;XIU Changyao;QIAN Rui;HUANG Mingwei;LIU Shuo(Liaoning Earthquake Agency,Liaoning Shenyang 110034,China)

机构地区：[1]辽宁省地震局,辽宁沈阳110034

出　　处：《防灾减灾学报》2025年第2期26-31,共6页Journal of Disaster Prevention And Reduction

基　　金：中国地震局2025年度震情跟踪一般性任务(CEA-ZQGZ-202501011)。

摘　　要：基于辽宁灯塔M5.1地震前的辽宁地球物理定点观测资料,分析了灯塔地震前地下流体与形变异常的时空演化过程,并讨论了震中周边300 km区域内异常的时空演化特征及成因,为辽宁弱震区中强地震预测提供参考。结果表明:(1)灯塔地震前,中、短期异常在震前7至10个月和1至3个月集中出现,特别是震前3个月,异常呈现出阶段性和准同步性特征,前兆异常在异常发展中存在形变-流体交替出现的演化特征;(2)异常主要分布在郯庐断裂带东侧的营口-铁岭约210 km长的条带上。趋势性异常在近场和远场(100~300 km)均有出现,而中短期异常则主要集中在近场(约100 km范围内),不同阶段异常在空间上均表现出由震中向外围扩散,再向震中收缩的特征;(3)震前异常时空演化特征主要受孕震过程中区域应力场变化的影响,并与区域内3级以上中等地震的活动水平及空间分布密切相关,综合两者进行分析,可为发震地点的预测提供有效判据。Based on the geophysical fixed-point observation data of Liaoning Dengta M5.1 earthquake,this study analyzed the abnormal spatial and temporal evolution process of underground fluid and deforma⁃tion before the earthquake,and discussed the characteristics and causes of spatiotemporal evolution of anomalies within a 300 km radius around the epicenter area.It provides a reference for the strong earthquake prediction in Liaoning weak earthquake area.The results showed that:(1)Medium and short-term anomalies are relatively concentrated in 7 to 10 months and 1 to 3 months before the earthquake.Especially in the three months prior to the earthquake,anomalies exhibited phased and quasi-synchronous characteristics,with precursor anomalies demonstrating an alternating evolution pattern of deformation and fluid anomalies during their development;(2)Anomalies were mainly distributed along a roughly 210 km long strip from Yingkou to Tieling on the east side of the Tanlu Fault Zone.Trend anomalies occurred both in the near-field and farfield(100~300 km),while medium and short-term anomalies were mainly concentrated in the near-field(within about 100 km).Anomalies at different stages spatially exhibited characteristics of diffusion from the epicenter to the periphery and then contraction towards the epicenter;(3)he spatiotemporal evolution charac⁃teristics of pre-earthquake anomalies were mainly influenced by changes in the regional stress field during the seismogenic process and were closely related to the activity level and spatial distribution of moderate earth⁃quakes(magnitude≥3)in the region.Comprehensive analysis of both factors can provide effective criteria for predicting the earthquake epicenter location.

关 键 词：灯塔地震 地下流体 形变 时空演化特征 成因 

分 类 号：P315.7[天文地球—地震学]