沂述带附近流动重力显著变化点分析及其地震预报效能评估

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关键词沂述断裂带；重力场变化；震中位置；地震预报效能评估中图分类号： P315.72+6 文献标识码：A 文章编号：2096-7780（2025）07-0395-12doi： 10.19987/j.dzkxjz.2024-087

AbstractThe area around which a gravitational field changes significantly is usually accompanied by measurement points with significant changes.To carryout analysis of the gravity field variation around the Yishu zone based on the analysis ofregional variation，the temporal variation of themeasuring pointsaround the significantchange area was analyzed in detail to verifyitscorrespondence with surrounding earthquakes.Inthis study，thedata difference between July 2022 and the previous periodand August 2O15 near the Yishu zone Was calculated，and peripheral measuring points with significant regional changes were selected through mapping toanalyze the preliminary correspondence between their timeseries changes and the surrounding earthquakes.The long-term data were analyzed and verified using an earthquake prediction efficiency evaluation software. The results showed that： ① The Guangrao area is affected by ground subsidence， the Changyi area is afected by changes in groundwater level，and the Zaozhuang and Zhangzhuang areas have some correspondence with the surrounding earthquakes. ② Only one out of ten evaluation items in the threshold category and trend-turning categoryof the five significant change measurement points failed to meet the evaluation criteria.Itcan be preliminarily concluded that the significant change measurement points near the Yishu Zone have agood monitoring efficiency for ML3.0 earthquakes within 100km of the measurement points.

KeywordsYishu fault zone; variation of gravity field; epicenter; evaluation of earthquake prediction efficiency

0 引言

地震是地下构造活动的一种表现形式，它的孕育及发生通常伴随着局部应力场的改变、地下物质迁移、地下密度变化等物理过程。（剩余13670字）