基于球面最小二乘配置的福建省地壳水平形变研究

Study on Horizontal Crustal Deformation in Fujian Province Using Spherical Least Square Collocation

利用GPS实测数据解算区域地壳应变率分布是现今地壳水平形变研究的一个重要手段。本文研究采用基于球坐标的最小二乘配置应变率计算公式,结合GPS实测速度场解算福建省东南沿海及其邻近区域应变率场。结果显示,福建东南沿海地壳形变主要受到来自印度板块与菲律宾板块对欧亚大陆的共同作用。区内主压应变率趋势强于主张应变率趋势。以九龙江断裂为界,以北地区地壳形变特征较为一致,断裂以南地区,自北东向西南,区域地壳形变逐渐变化,呈现离散化、多样化的特征。

Calculating strain filed distribution with GPS measurement data has been an important mean to study the present-day crustal horizontal deformation. A series equations of the strain-field calculation based on spherical standard are deduced in this paper. Then calculate the GPS strain field in Fujian province using the equations. The result shows that the crustal deformation of the study area mainly affect by India plate and Philippine plate. Regional compressive strain rate is stronger than its tensile strain rate. Separated by Jiulong river fault zone, the northern crustal deformation trends have similar characteristics and the southern part of the regional crust has diverse characteristics from N-E to S-W.