福建地区现今地壳运动与形变研究

RESEARCH ON PRESENT-DAY CRUSTAL MOVEMENT AND DEFORMATION IN FUJIAN AREA

利用福建地区GPS地震监测网2003、2005和2008年3期的观测资料,计算了GPS点位运动速率和2008年切应变的分布。结果显示:GPS点位运动矢量的主要方向是东偏南,大小在40 mm左右。2003—2005年和2005—2008年两个时期的速度场量值差异不大,但运动方向有所改变。切应变在莆田至福州以及泉州至莆田,越靠主干断裂剪切应变越小,断裂两侧剪切应变差异不显著;厦门至漳州沿海一带,向沿海方向剪切应变逐渐增大;在厦门至泉州之间靠近厦门一侧,存在相对较大的剪切应变梯度带。

By utilizing the observations of the 2003, 2005 and 2008 from Fujian GPS seismic monitoring network, the movement velocities of GPS stations and distribution of shearing strain in Fujian aera in 2008 are calculated. The results are as follows. The direction of movement vector of GPS stations in Fujian aera is generally east by south, and the value is about 40 millimeters. Velocity field values of two periods of 2003 - 2005 and 2005 - 2008 are almost the same, but the direction changed somewhat. As regards the shearing strain, between Putian and Fuzhou and between Quanzhou and Putian it becomes less, as the place is more close to main fault, is increasingly small on major fracture zone, and coastal area between Xiamen and difference between shearing strains on the two sides of fault is not evident. In Zhangzhou, and Between Xiamen and Quanzhou and near Xiamen, approaching to the sea, shearing strain is gradually increasing. there exists a relatively bigger gradient zone.