2022年青州M_(L)4.1地震前后的重力场变化分析

Analysis of the Change of Gravity Field before and after the 2022 Qingzhou M_(L)4.1 Earthquake

以2022年青州M_(L)4.1地震为研究目标,根据先前学者总结的区域重力场变化在大震孕育发生中的异常特征,通过计算相邻两期重力变化、累计重力变化的方式,分析了震中附近变化的空间尺度和数量级。本文分析了区域重力场变化显著地区的测点单点变化情况,包括高炳西、济南站、王坟及庙子等测点,以及高炳西场地南北两测点重力差的变化情况。根据高炳西场地南北两测点周边干扰情况,包括降水量、地面沉降、地形改正等,分析了该两测点重力差变化的原因。本文认为青州ML4.1地震发震前后的重力场有变化,且该变化与地震孕育发生导致的地下物质迁移有关。

In this paper,the 2022 Qingzhou M_(L)44.1 earthquake was taken as the research target.According to the abnormal characteristics of regional gravity field changes in the preparation and occurrence of large earthquakes summarized by previous scholars,the spatial scale and order of magnitude of changes near the epicenter were analyzed by means of calculating gravity changes in two adjacent periods and cumulative gravity changes.The variation of the single point of the measuring points in the area with significant variation of regional gravity field,including Gaobingxi,Jinan Station,Wangfen and Miaozi,as well as the variation of gravity difference between the north and south of the Gaobingxi site,was also analyzed.According to the surrounding disturbance of the two measuring points in the Gaobingxi site,including the precipitation,land subsidence and terrain correction,the reasons for the change of gravity difference between the two measuring points were analyzed.It is suggested that the gravity field changes before and after the Qingzhou M_(L)44.1 earthquake,and the change is related to the underground material migration caused by the earthquake preparation and occurrence.