厦门重力固体潮海潮负荷改正研究  

Study on ocean tidal loading correction of tidal gravity at Xiamen Station

作　　者：杨锦玲[1] 关玉梅[1] 钟继茂[1] 洪旭瑜[1] 

机构地区：[1]福建省地震局,福州350003

出　　处：《地球物理学进展》2016年第3期992-998,共7页Progress in Geophysics

基　　金：福建省地震局科研基金专项(SF201513);福建省地震局青年科技基金(Y201305)联合资助

摘　　要：厦门台重力固体潮观测长期受海潮负荷影响.应用重力固体潮观测资料进行地震预报和地球物理研究时,需要对其海潮负荷的影响和改正进行研究.本文应用TSOFT软件对厦门台弹簧重力仪五年的连续观测数据进行预处理,并采用Venedikov调和分析方法获得重力固体潮潮汐参数.基于DTU10、EOT11a、HAMTIDE11a、GOT4.7、FES2004、NAO99b、TPXO7.2和TPXO7.2atlas八个较新的全球海潮模型,结合osu.chinasea.2010和NAO.99Jb两个区域海潮模型,研究了厦门台的重力海潮负荷特征并对其进行海潮负荷改正.数值结果表明,经过区域海潮模型修正后的厦门台海潮负荷为7.3μgal.八个全球海潮模型对主要潮波的负荷改正有效性的差异不大.应用NAO.99Jb区域海潮模型修正的M2波剩余残差值比osu.chinasea.2010小.观测残差负荷改正有效性大致在40%-70%.统计对比O1、K1、M2波的残差平方和结果表明,对厦门台进行海潮负荷改正时,应用经NAO.99Jb区域海潮模型改正的NAO.99b全球海潮模型残差结果最小,经NAO.99Jb区域海潮模型改正的DTU10全球海潮模型次之.这可能与NAO.99Jb模型考虑日本沿岸验潮站资料有关.考虑高精度近海海潮模型的构建和验潮站资料的弥补以及数据预处理方法的改进,可以进一步提高厦门台的海潮负荷的改正效果.Tidal gravity observation at Xiamen Station is critically affected by ocean tide loading（ OTL）. To obtain high-precision tidal gravity parameters and apply them to earthquake prediction and geophysical research,calculation and correction of the OTL effect is required. In this study,tidal gravity data through 5 years were preprocessed based on the Tsoft software,which is recommended by the International Center of Earth Tides, and then precise tidal gravity parameters were obtained using Venedikov method for tidal analysis. In order to evaluate the efficiency of different ocean loading corrections,gravity data were analyzed for various tidal waves（ O1,P1,Q1,K1,M2,N2,S2,K2） based on eight up-to-date global OTL models（ DTU10,EOT11 a,FES2004,HAMTIDE11 a,NAO99b,TPXO7. 2,and TPXO7. 2atlas）,supplemented with two regional oceanic models（ osu. chinasea. 2010 and NAO. 99Jb）,in combination with an ocean loading calculation program（ SPOTL）.The numerical results show that,the average OTL effect at Xiamen Station was 13. 9 μgal when calculated with the global oceanic tidal models. After supplementation with the two regional ocean models,the average OTL effect decreased to 7. 3 μgal. The values of the ocean tide corrections had relatively small discrepancies between the eight global models. The final residual of M2 harmonics supplemented with NAO. 99 Jb was smaller than that with osu.chinasea. 2010. The loading effect efficiency varied from 40% to70% for the three major waves（ O1,M2,K1）,indicating that the remaining load effects might have been from the atmosphere,tidal force caused by regional tectonics,and observation errors. From comparisons of the combined misfit for the three major waves,the most optimum ocean tide model was found to be NAO. 99 b supplemented with NAO. 99 Jb, followed by the DTU10 model supplemented with NAO. 99 Jb. This shows that the Nao. 99 Jb regional OTL model, which takes into account tide gauge measurements,is more suitable for Xiamen Station than osu.chinasea. 2010. To impr

关 键 词：重力固体潮 海潮负荷 海潮模型 潮汐分析 

分 类 号：P312[天文地球—固体地球物理学]