【摘要】 利用中国大陆以及蒙古、缅甸、印度、尼泊尔和喜马拉雅等周边地区多年的GPS观测资料, 基于连续介质假设, 采用双三次样条函数模拟方法, 给出中国大陆整体水平位移速度,拟合精度优于3 mm/a, 获得了中国大陆的水平应变率场, 并分析了中国大陆现今构造变形、水平应变率场的空间分布特征. 结果表明: 对大范围、密集的GPS速度场的连续变形分析,既能揭示中国大陆现今构造变形的总体特征, 又能显示局部地区现今的构造活动特征. 总体上, 中国大陆构造的水平变形强度和变形速度在南北地震带产生突变, 呈西强东弱、南强北弱态势. 而昆仑山地块中部、鲜水河断裂带和云南中部地区, 其应变速率最大, 速度变化最快; 阿尔金断裂带现今处于其构造活动的平静期, 中天山东部地区具有拉张环境.更多还原

【Abstract】 Assuming that the contemporary tectonic activity in China can be treated as continuous, we have simulated 1245 present day multiple epoch GPS velocity solutions in the range of Chinese mainland, Mongolia, Myanmar, India, Nepal and Himalayas with a bi cubic spline interpolation function to inverse the integral horizontal velocity with the fitting accuracy less than 3 mm and obtained the strain rate fields in Chinese mainland. We have also analyzed the characteristics of spatial distribution of horizontal deformation and strain rate fields in Chinese mainland. The result shows that the analysis on the continuous deformation in the large scale and dense GPS velocity fields can reveal not only the integral tectonic characters of Chinese mainland but also the tectonic characters in local regions. Generally, the magnitude and intensity of horizontal tectonic deformation have a mutation in the South North Seismic Belt, which is stronger in the west than the east and stronger in the south than the north. Large strain rates are found in the areas as Kunlun block, Xianshuihe fault zone and central Yunnan, and the variation of velocity is very rapid. At the same time, the tectonic activity is relatively calm on Altyn Tagh fault zone, and extensive strain is found in the eastern part of central Tianshan.更多还原