利用华北地区2009—2014年绝对重力与相对重力多期重复观测资料,得到不同时空尺度的华北区域重力场动态变化图像。采用欧拉反褶积方法,通过对理论模型试算,获得最优反演参数,对引起华北地区重力场变化的场源深度和空间分布规律进行了反演计算和分析。结果表明:当构造指数为1时,适合对流动重力场变化数据进行反演。实际资料的反演结果在2009—2014年间的场源位置集中于河套断裂带。本文研究方法可以用于重力场反演和以场求源的定量研究。本工作为流动重力变化信号的反演和解释提供一条新思路,也为构建地震重力预报指标体系提供了定量依据。
Based on absolute and relative gravity observations from 2009 to 2014in north China,the results of spatial dynamic variation of regional gravity field are obtained.We employed Euler deconvolution method based on theoretical model to get a better estimation of source parameters.Gravity field changes caused by depth and distribution in north China were calculated by back analysis.The results show that it is suitable to inverse gravity variation data when the structural index equals one.The inversed results indicate that positions and depths of anomaly sources spread over Hetao fault.Our method is capable to provide quantitative research related to the field source and may shed new light on the interpretations on the gravity change,and also can provide quantitative basis for earthquake prediction index criterions based on gravity changes.