基于绝对重力基准控制的流动重力观测资料动态平差方法研究  

Method of Dynamic Adjustment on Repeated Gravity Measurements under the Constraint of Absolute Gravity Observations

作　　者：康开轩[1,2] 李辉[1,2] 申重阳[1,2] 孙少安[1,2] 郝洪涛[1,2,3] 

机构地区：[1]中国地震局地震研究所(地震大地测量重点实验室),武汉市洪山侧路40号430071 [2]中国地震局地壳应力研究所科技创新基地,武汉市洪山侧路40号430071 [3]中国科学院大学,北京市玉泉路甲19号100039

出　　处：《大地测量与地球动力学》2015年第3期508-511,516,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震行业专项(201308004;201208009);国家自然科学基金(41004030;41304059);中国地震局地震研究所发展基金青年创业基金(IS201026092)

摘　　要：选取滇西重力测网1986~2009年流动重力观测资料及下关、丽江、昆明3个绝对重力基准点多年复测资料作基准控制,采用线性速率模型拟合观测过程中重力场的时变信息,建立绝对重力基准点约束下的动态平差模型,讨论段差观测值及绝对重力基准观测值协方差矩阵的构建、平差模型初值选取及迭代计算等细节问题。经分析,测区内测点的重力年变率范围为（-0.039 5~0.024 1）×10-5 ms-2/a,精度范围为（0.001~0.029 8）×10-5 ms-2/a,与分期静态平差拟合结果的差异约为（0.003~0.020）×10-5 ms-2/a。在处理全国网和较大面积的区域网多年重复观测的重力资料时,尤其是多网多期重力资料联合处理时,应采用动态平差模型来获得统一时间基准和空间基准的重力变化。In this paper we use the repeated gravity measurements of the western Yunnan gravity net- work with the data length of 1986-2009, as well as absolute gravity observations at Xiaguan, Lijiang, and Kunming gravity sites. Linear gravity rate models are employed to estimate the time variation ge- ophysical information. We build dynamic adjustment models under the constraints of absolute gravity observations, and discuss several key questions including the variance metric for both repeated and ab- solute gravity measurements, the initial values of the models and the iterations ~, robust estimation, and statistic hypothesis testing. We obtain the annual gravity rate at each site in the western Yunnan network with a range of （--0.039 5-0. 024 1）N10 5ms 2/a, and the precision with a range of （0.001- 0.029 8） X10-Sms-2/a, with the difference of （0.003-0.020）X10 ~ms 2/a, as compared with the static adjustment method. When we process the national gravity network or the regional gravity net- work over a relatively large area, especially with multi-network and multi-campaign gravity measure- ments, the dynamic adjustment model developed in this work can ohtain the gravity variation under the united space-time status.

关 键 词：流动重力观测 动态平差 重力年变率 绝对重力基准 时间基准 

分 类 号：P315.7[天文地球—地震学]