基于多种GPS数据研究福建及其邻近海域1994-1997年地壳水平运动

STUDY ON THE CRUSTAL HORIZONTAL MOVEMENT IN FUJIAN AND ITS NEIGHBOURING SEA REGION IN 1994 TO 1997 BASED ON SEVERAL KINDS OF GPS SURVEYING DATA

为研究中国大陆东南部的边缘海动力学，基于中国大陆和福建区域的ＧＰＳ观测网 以及环绕中国大陆的ＩＧＳ（Ｉｎｔｅｒｎａｔｉｏｎａｌ ＧＰＳ Ｓｅｒｖｉｃｅ）跟踪站在１９９４—１９９７年间的测量数据， 建立块体运动和块内变形两种力学模型，研究了福建及其邻近海域现今地壳水平运动速度场 和应变率场．结果表明：无论在中国大陆还是在中国大陆周边框架内，或相对于台湾而言，福 建及其邻近海域均整体地向着东南或东偏南方向，即指向海洋的方向作水平运动．运动平均 速率为１１．２±３．０ｍｍ／ａ（福建网）或１４．０±４．０ｍｍ／ａ（全国网）．然而在福建区域内还存在着 一种由海洋指向大陆内部的北西向运动，其运动平均速率为 ３．０± ２．６ｍｍ／ ａ．区域应变率场 主压应变方位为ＮＷ（ＮＷＷ）－ＳＥ（ＳＥＥ）．印度板块对欧亚板块的碰撞通过中国大陆内部各 块体间的侧向传递和菲律宾海板块对台湾（欧亚大陆东南沿）的仰冲与挤压，同时作用到福建 及其邻近海域。此种联合作用现今仍在继续进行中，前者的影响比后者更强烈，但前者形成的 速率场均匀，而后者不均匀。

This paper provides a foundation for studying dynamics of marginal sea on the southeast of China mainland. It is based on the data from GPS observation metwork of China continent and Fujian region as well as the data of IGS (International GPS Service) tracing stations around China continent during the years of 1994 to 1997. Two mechanics models of blocks movement and intra-block deformation are established. Velocity and strain rate fields of present-day crustal horizontal movement in Fujian and its neighbouring sea region are firstly studied. The results indicate that Fujian and its neighbouring sea region as a whole horizontally moves towards southeast or east-southeast namely towards sea, not only in China continent frame-work or in around China continent frame work, but also relative to Taiwan. The average velocity is 11.2 + 3.0mm/ a (by Fujian GPS network) or 14.0 ± 4.0mm / a (by China GPS network). Meanwhile, in Fujian area there is a northwest movement directing from sea to hinterland. The average velocity is 3.0 ± 2.6mm / a. The principal compressive axis of regional strain rate field lies in NW (NWW)-SE (SEE). The collision of indian plate and Euro-Asian plate affects Fujian and its neighbouring sea region by several blocks' side-transferring in China continent. The obduction and jam of Philippines-sea plate to Taiwan (southeast margin of Euro-Asia continent) also affects this region. The jointly affection still exists today. The former is stronger than the latter while the velocity field of the former is homogeneous and the one of the latte is not homogeneous.