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基于ITRF2008参考架下225个GPS测站的速度场对NNR-MORVEL56板块运动模型中13个板块的运动参数及不确定度进行估计。在测站的筛选过程中,利用全球应变率模型GSRMv1.2的结果对测站第二不变应变率进行双三次二维平面插值,若测站的第二不变应变率小于10-14/a,则测站位于板块的刚性区域。考虑到冰期回弹对测站速度场的影响,基于冰期回弹模型ICE-3G(VM2),用TABOO直接对测站的水平位移速率进行定量计算,若冰期回弹引起的测站水平位移速率大于0.5mm/a,则测站位于GIA地区,应予以剔除。分别比较本文计算结果、Altamimi计算结果和基于地质资料的MORVEL板块运动模型,结果显示本文建立的板块运动模型具有较高的精度,所采用的测站筛选准则具有可行性。简要分析了本文和Altamimi计算结果的差异以及个别板块偏差较大的原因。

The kinematical parameters for 13 major global plates within NNR-MORVEL56 plate motion model, as well as their standard devations, have been estimated in this paper, using velocities from 225 GPS sites with respect to ITRF2008. During the process of site selection, we obtained the second invariant strain rate (SISR) field of sites by the bicubic interpolation method according to the GSRMv1.2, supposing a site should be located in the rigid region if its SISR is lesser than １０－１４／ａ. Given the effects of postglacial rebound on the sites' velocity, this paper employed a quantitative calculation to the horizontal rate of the sites based on the ICE3G-VM2 model through the TABOO software, assuming that sites with a horizontal rate greater than 0.5 mm/a belongs to GIA region and should be eliminated. In the end of this paper, our results have been compared with the results by Altamimi and the MORVEL based on geological data respectively, showing that models established in this paper display a relatively high accuracy with the feasibility of site selection criteria adopted, and at the same time, the differences between these results and reasons causing kinematic deviation in several plates have also been illustrated.