利用CORS站网监测三峡地区环境负荷引起的地壳形变与重力场时空变化

Monitoring Temporal and Spatial Changes of Crustal Deformation and Gravity Field Caused by Environmental Load in the Three Gorges Reservoir Region Based on CORS Network

受地球动力学因素特别是地球表层大气、地表水及地下水动力环境影响,地面站点位置、地球重力场及大地水准面随时间变化。以三峡地区CORS站网为主,少量重力台站为辅,采用负荷形变与地球重力场严密组合方法,综合确定了2011-01-2015-06三峡地区环境负荷驱动的地壳形变与重力场月变化,结果显示：（1）CORS站网具备地壳垂直形变、大地水准面及地面重力变化的监测能力;（2）三峡地区地壳垂直形变年变化幅度36.1mm,大地水准面年变化幅度28.2mm,地面重力年变化幅度117.4μGal;（3）CORS站网地面重力变化监测精度水平不低于流动重力场重复测量;（4）CORS站网地壳垂直形变与地面重力变化监测具有一定的外推预报能力。

Due to the geodynamic factors,especially the earth＇s surface atmosphere,surface water and groundwater hydrodynamic environment,ground site location,earth gravity field and geoid level change over time.Based on the Three Gorges CORS stations network and a small number of gravity stations,the crustal deformation and monthly gravity change of the Three Gorges area from January2011 to June 2015 are calculated and analyzed in this paper by combination of load deformation and gravity field.The results show that：（1）CORS network has the ability to monitor the vertical deformation of the crust,ground gravity and geoid change.（2）The annual variation of the crustal vertical deformation in the Three Gorges area is 36.1 mm,the annual variation range of the geoid is 28.2 mm,and the annual variation of ground gravity is 117.4μGal.（3）The accuracy of ground gravity change monitoring level of CORS network is not lower than the accuracy of flow gravity field.（4）Vertical deformation and ground gravity change monitoring has a certain ability of extrapolation forecasting.