深部场源变化微重力观测系统设计与模型研究

摘要

Based on the microgravity method for the repeated surveys,regional time-lapse gravity changes can be detected.Using this method,the monitoring capability for the crustal deep mass changes can be established.In this paper,we propose a novel gravity array observation system,which jointly uses the high-precision absolute gravity,relative gravity,leveling,GNSS instruments and hydrological meters in the optimal observation station,on the basis of earthquake monitoring system.The key advantage of this approach is it isolates the microgravity signal with respect to the different field source depths.Moreover,except for improving signal noise ratio related to the deep source,the parameters of arrayed observation can be adjusted for monitoring special sensitive regions.The results are beneficial to estimating the crustal deep mass variation and help us to understand the earthquake preparation and the cause of geophysical field changes as the direct scientific evidence.%基于陆地μGal级精度的重力重复测量可以获取高精度区域重力场时变信号,实现对地壳内部介质物性变化的监测能力.提出一种基于现有地震重力监测网络,通过优化场地观测条件,联合应用高精度绝对重力、相对重力,联合水准、GNSS系统和水文等观测手段,设计一种新型的场地重力阵列式观测系统,有助于分离不同深部场源引起的微重力变化信号.该观测系统除可以提高地壳深部场源信号的信噪比外,还可以通过调整阵列间距来监控敏感区场源变化,有助于探测地壳深部地震孕育和发生阶段的场源介质物理变化过程.