高精度GPS观测及其在福建东南沿海地壳形变研究中的应用

HIGH PRECISE GPS OBSERVATION AND ITS APPLICATION TO THE CRUSTAL DEFORMATION STUDIES IN SOUTHEAST COAST OF FUJIAN PROVINCE

对福建东南沿海ＧＰＳ地壳形变监测网的两期观测资料的处理方法及其精度进行了深入讨论，并根据复测资料的对比，对该地区现今地壳运动的基本特征进行了初步的分析。结果表明两期ＧＰＳ观测资料经严密处理后其基线重复性精度优于１０－ ８，高程分量的精度固定误差小于７ｍ ｍ ，比例误差优于１０－ ８，满足了研究该地区现今地壳运动的基本需要。利用统一处理后的两期ＧＰＳ观测结果获得了该地区现今地壳运动的基本图象，表明该地区相对于全球ＩＴＲＦ框架整体呈南东东向运动，台湾和福建沿海大陆相对运动是北西向压缩。这个结果和本地区北西向主压应力的构造应力场状态一致。ＧＰＳ测区范围内测点的相对运动表明测网所跨越的北东、北东东向断裂呈右旋走滑趋势，其活动量为毫米。

The processing method and precision of two stages of GPS data for the crustal deformation monitoring in southeast coast of the Kujian Province are discussed in more detail, and the main features of current crust movement are primarily analysed by comparing the two stages of GPS obserrations. The results show that the repeatability accuracy of base line between two stages of GPS data is better than 10 -8 and the errors of elevation and propartion are less than 7mm and 10 -8 respectively, which all meet the basic needs for studying recent crust motion in the area. The basic pattern of crustal movement in the area is obtained by using two stages of GPS data unitedly processed. It is shown that the crust in the area moves along SEE direction in the globe ITRF corrdinate frame. The relative motion between Taiwan and continent of Fujian coast causes the crust to be compressed along NW direction. this result is consistent with the tectonic strain field of the EN main compressive strain in the area. The relative movements of observation points show that the NE and NEE fault crossed by the GPS metwork have the right-lateral strike slip tendency and the motion by micrometers.