选取2017—2023年乌加河地震台周边500 km范围内10个MS≥4.0地震事件(其中2个震例发生在蒙古),以台站记录的地电场数据资料为研究对象,基于地电场潮汐波岩体裂隙水(电荷)渗流模型,计算并分析地震发生前后优势方位角变化特征。研究结果显示,在所选10个震例中,6个地震事件方位角在震前1—2个月出现显著变化,震后逐渐回归正常,其中5个震例方位角呈增大趋势、1个震例呈减小趋势变化,且在方位角显著变化期间,数据点空间分布表现出分散和紧密2种形态。这些震例的累积对于深入研究地震地电场异常特征和地震活动规律,具有重要意义。
10 MS≥4.0 earthquakes (including 2 events that occurred in Mongolia) within 500 km around the Wujiahe Seismic Station from 2017 to 2023 were selected to calculate and analyze the characteristics of the dominant azimuth of the geoelectric field before and after the earthquakes based on the geoelectric field tidal wave rock mass fracture water (charge) seepage model. The results show that among the selected 10 earthquakes, the azimuth angles of 6 events changed significantly 1-2 months before the earthquake and gradually returned to normal after the earthquake, among which the azimuth angle of 5 events showed an increasing trend and 1 event showed a decreasing trend. The accumulation of these earthquake cases is of great significance for the in-depth study of the anomaly characteristics of the seismic geoelectric field and the law of seismic activity.
2025,46(1): 71-77 收稿日期:2024-7-19
DOI:10.3969/j.issn.1003-3246.2025.01.010
基金项目:内蒙古自治区地震局局长基金(项目编号:2023QN27)
作者简介:刘伟(1988—),男,工程师,主要从事地震监测预报工作。E-mail:348804840@qq.com
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