连续GPS测定的天山及其邻近地区垂向运动特征

Vertical motion characteristics of Tianshan and its adjacent areas measured by continuous GPS

基于中国大陆构造环境监测网络31个GPS连续观测站2011-2018年垂向坐标时间序列结果,顾及地壳垂向周期性运动得到了天山及其邻近地区的地壳垂直运动特征,结果表明:研究区内地壳垂直周期性运动显著,以年周期运动为主;大部分GPS连续站的年周期运动振幅在1.5~3.5 mm;27个测站半年周期通过检验,与年周期运动相比,其振幅较小,多在0.5 mm左右;天山及其邻近地区的地壳垂直线性运动呈山体隆升、盆地下降的趋势,显示该区域的长期地壳垂直运动为继承性,具体而言,塔里木地块的平均垂直运动速率为-0.88 mm/a,天山地块为0.25 mm/a,准噶尔地块为-0.29 mm/a.设计了三种垂向线性速率的求解方案,验证了求解地壳垂直线性运动速率时剔除非构造运动信息的必要性.

Based on the vertical coordinate time series results of 31 GPS continuous observation stations in Crustal Movement Observation Network of China from 2011 to 2018, the GPS vertical crustal motion characteristics of Tianshan and its surroundings were obtained by taking into account the vertical periodic motion of the crust. The following conclusions are drawn: the vertical periodic motion of the crust in the study area is significant, and the annual cycle motion is the main one;most of the GPS continuous stations have an annual period motion amplitude of 1.5~3.5 mm;27 stations have passed the test for half-year period, compared with the annual cycle motion, the amplitudes of half-year period are smaller, mostly around 0.5 mm;the overall trend of the vertical linear motion in the study area is the uplift of the mountain and the decline of the basin, indicating that the long-term crustal vertical movement in this area is inherited, specifically, the average vertical motion rate of the Tarim block is-0.88 mm/a, the Tianshan block is 0.25 mm/a, and the Junggar block is-0.29 mm/a. In this paper,three deriving strategies were also designed to verify the necessity of removing the nontectonic motion information when solving the vertical linear motion rate of the crust.