用甚长基线干涉测量数据检测冰期后地壳回弹

Detection of postglacial rebound by using VLBI data

本文利用甚长基线干涉测量(VLBI)技术提供的实测站速度和地球物理模型ICE_4G提供的数据,采用实测站速度法和基线长度变化率法分别检测了冰期后地壳回弹的垂直运动和水平运动.对用空间技术求解的实测值和用ICE_4G模型求解的估计值进行线性拟合和相关分析,两者的相关系数达到0 8～0 9,表明空间技术已经能够检测1～10mm a的冰后回弹运动;在方向上两者基本一致,在量级上,实测结果的绝对值比模型估计值系统性的偏大约2 0 % ,表明当前冰期后的地壳回弹运动比地质时期要猛烈.

This paper discusses the detection of postglacial rebound by using data from space geodetic measurement of VLBI, and using measured site velocities and length rates of baselines to detect the vertical and horizontal postglacial rebound respectively. The comparison and correlation analysis between space geodetic results and predictions of postglacial rebound from the geophysical model ICE-4G shows that they have good agreement, their high correlation coefficients reach to 0.8～0.9, which indicates that the space techniques now have been able to detect postglacial rebound at 1～10mm/a level. But in magnitude, space geodetic results are generally 1.2 times larger in absolute value than ICE-4G predictions, which shows that the current postglacial rebound motion is more violent than the geophysical predictions.