四川省CORS网地壳运动速度场模型研究

摘要

使用GAMIT/GLOBK解算2006～2015年覆盖四川地区的50个CORS站的观测数据,并提取坐标时间序列,获得速度场模型.对四川省整体地壳运动以及区域应变场进行分析,结果表明,四川省CORS站水平方向平均速度为38.72 mm/a,速度场的优势方向为S73.9°E;欧亚框架下水平方向平均速度为14.40mm/a,优势方向为S77.78°E,较ITRF2008框架下的速度降低了24.32 mm/a;垂直方向平均速度为3.43mm/a,整体上表现为隆升状态,位于东部平原的少部分测站处于下降趋势,可能是由于城市建设、地下水或者煤矿、石油等自然资源的过度采伐导致;最大主应变率达到7.31×10-11 /a,最小主应变率为-5.4×10-11/a,其中区域地壳面膨胀率高值区域集中在川西,低值区域和最大剪切应变率高值区域分布在三大断裂带附近.%In this paper,GAMIT/GLOBK is used to solve the data of 50 CORS stations covering Sichuan province from 2006 to 2015,and the time series is extracted and the velocity field model is obtained.The results show that the average velocity of CORS stations in Sichuan is 38.72 mm/a,and the advantage direction of velocity field is S73.9°E.The average velocity in the horizontal direction of Eurasia is 14.40 mm/a,the dominant direction is S77.78°E,which is 24.32 mm/a lower than the ITRF2008 frame.The average speed in the vertical direction is 3.43 mm/a,the whole is uplifted,and a small part located in the east plains of the station are in a downward trend,probably due to groundwater or excessive logging of natural resources such as coal mines and oil.The maximum principal strain rate is 7.31 × 10 ~/a and the minimum principal strain rate is-5.4× 10 11/a.The regional crustal surface expansion and maximum shear strain rate are distributed in the southwest near the three fault zones.