中国大陆重力场非潮汐时空变化特征的初步分析  

The preliminary analysis to the temporal variation characteristics of non-tidal changes of gravity in China's Mainland

作　　者：徐伟民[1] 陈石[1] 高孟潭[1] 卢红艳[1] 李真[2] 

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]中国地震局地球物理勘探中心,郑州450002

出　　处：《地球物理学进展》2012年第3期861-871,共11页Progress in Geophysics

基　　金：中国地震局地球物理研究所基本科研业务专项(DQJB09A02;DQJB11C14)资助

摘　　要：本文基于Tsoft软件在潮汐数据预处理中的应用,采用Tsoft数据预处理软件和别尔采夫滤波相结合方法,提取了覆盖中国大陆28个重力固体潮台站连续观测数据的非潮汐分量.对各台站2008～2011年的连续数据,进行了缺失数据补接、地震动事件提取和去除非线性漂移等预处理工作,并通过滤波提取固体潮非潮汐分量.结果表明:除在贵阳、勐腊和十堰3个原始数据质量较差的台站外,其它台站观测数据应用本文方法均取得良好的结果.在此基础上,对处理结果采用滑动平均,将非潮汐分量结果的月均值与GRACE卫星和CMAP降水记录的月采样数据进行对比,结果显示了地表降水同重力变化具有一定相关性特征.此外,基于Tsoft软件的分段曲线漂移拟合能有效去除原始数据中的漂移.Tsoft software is widely used in preprocessing tidal dataset, and it had been proved to be an effective way to process tidal data. But it has been only used to extract tidal information , in this paper we try to use it to extract non-tidal information. Following that we claim a new method to extract non-tidal changes of gravity from tidal station based on Tsoft software and Pertesv＇ s filtering. The Tsoft software maibly used to preprocess original dataset to clear away different kinds of interference, and the Pertesv＇s filtering is one of the best way to extract nontidal information so far, which has been widely used in related studies. Based on the new method, we process and analysis the gravity data of 28 tidal stations in China's Mainland in past 3. 5 years （2008. 1 ~ 2011. 5）, the preprocessing to the original data contains fill in data gaps, extract earthquake events, remove the drift and so on. The results show that the non-tidal variation based on the new method has high precision in almost all tidal stations except only 3 stations .. Guiyang, Mengla and Shiyan, in which the original data is extremely bad. Following that we compared the non-tidal information with the computed results of GRACE satellite data and the rainfall information from CMAP, and the results indicate that the new method claimed in this paper is accurate and credible. Besides that, we also find the correlation characteristics between rainfall and gravity variations, which had been explained by other scholars. Meanwhile, to remove the drift in original gravity tidal data, we try to present a new way Curve fitting based Tsoft software, which is more simple to remove the drift than the current ways. And then we comparing the tidal data which removed drift with the theory gravity tidal, which shows that we remove the drift effectively through the new way. Overall, the new method we claim in this paper is a high precision and accuracy method to extract non-tidal variations from the original data of tidal stations, and it may be wide

关 键 词：Tsoft软件 漂移拟合 非潮汐分量 卫星重力变化 降水量 

分 类 号：P312[天文地球—固体地球物理学]