利用连续GPS观测数据分析长江三角洲地区地壳变形

An Analysis of the Crustal Deformation in the Yangtze River Delta Area Using Continuous GPS Observations

利用长江三角洲区域内19个GPS连续运行参考站2007-2013年间的观测数据,计算得到了该区域ITRF2005参考框架下的三维速度场、应变参数及区域参考框架下的速度场。结果表明,在ITRF2005框架下,水平方向平均速率为33.97mm/a,优势方向为NE111.5;相对于欧亚板块的水平方向平均速率为9.36mm/a,优势方向为NE85.6;高程方向以沉降为主,最大沉降速率为15.22mm/a,平均沉降速率为4.7mm/a;该区域块体以N29.4E的拉张为主,达到2.4×10^-9/a,同时兼有N119.4E的挤压,达到1.3×10^-9/a。

The GPS observations from 19 continuously operating reference stations distributed in the Yangtze River delta area from 2007 to 2013were processed using the GAMIT/GLOBK software package,and the estimated coordinate time series were used to determine the velocities of reference stations in the ITRF2005 frame.Strain parameters and velocities relative to the Eura-Plate were also estimated.These results show that Yangtze River delta area moves at 33.97mm·a^-1 in the NE 111.5＂direction in the ITRF2005 frame,while the average horizontal velocity relative to the Eura-Plate is9.36mm·a^-1 in the direction of NE 85.6＂.In the vertical direction,the maximum subsidence rate is15.22mm·a^-1,and the average rate of subsidence is 4.7mm·a^-1.The maximum extension rate is2.4×10^-9/a and with the compressing rate of 1.3×10^-9/a in the direction of N 119.4 ＂E.