摘要
为了检验体潮与海潮的理论模型,分析了中国东西重力潮汐剖面(1981年9月—1985年1月)。同时,为研究LaCoste ET-20和ET-21重力仪的格值系统,建立了一条由17台LaCoste G型和2台LaCoste D型重力仪观测的重力垂直基线。在基线上标定的结果表明,ET-21重力仪的格值大了1%。由标定得到的格值计算剖面上各测站的潮汐因子,经海潮改正后,接近Wahr模型值,振幅因子的残差:O_1波小于0.3μGal,M_2波小于0.4μGal。但是上海和拉萨的观测经海潮改正后,相位迟后有很大的改善,振幅因子却更偏离于模型值,其潮汐异常主要是近海的海潮模型不完善,以及在海潮计算中,所采用的地球模型未考虑地壳与上地幔的横向不均匀性所引起。
In order to examine the theoretical Earth body tides and oceanic models, East-West gravity tidal profile of China is analysed. A vertical gavity baseline using 17 LaCoste G and 2 LaCoste D gravity meters has been established for checking manufacturer's calibrations of LaCoste ET model 20 and 21 gravity meters. The results of calibrations on the gravity baseline show that the manufacture's calibration of ET-21 is higher by 1%. The gravity tidal factors for all stations of profile have been calculated using ET-21 calibration coefficient. The tidal factors after ocean tides correction approach to the value of Wahr model and the residuals of amplitude factors are less than 0.3 μGal for O1, 0.4μGal for M2. However, the corrected tidal factors M2 at Shanghai and Ihasa stations, the phase lags are much better than before, but the amplitude factors deviate from the value of the theoretical model. Because the Shanghai station is near the Hangzhou Bay and Lasa is near Bay of Bengal and located at a place where the crustal thickness is larger and varies quickly, the tidal anomalies may be caused by ocean model and lateral heterogenity of the lithosphere and upple mantle.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第1期62-69,共8页
Chinese Journal of Geophysics
关键词
潮汐剖面
重力潮汐
格值
潮汐因子
Calibration, Vertical gravity baseline, Gravity tidal factor, Tidal anomaly, China.