中文摘要：

通过对渭河盆地地壳运动趋势和应变场特征分析,可为该地区的地震活动性研究等提供有价值的数据参考。采用反距离加权法计算地壳水平应变模型,利用观测点的位移值以及计算点与观测点之间的距离推导出计算点的位移函数,通过求导计算区域应变场的分布。结合渭河盆地1999年~2002年的GPS观测资料,计算了该区域地壳水平应变分布情况,结果表明：渭河盆地的主应变在空间分布上呈现不均匀的分布现象,盆地、山区的应变性质截然相反,盆地处于明显的拉张状态,山区则处于挤压状态。沿西安—临潼一线两侧剪应变对称分布,盆地内部西起马昭—西安—临潼—渭南一带剪应变都出现负值,汤峪以南,宝鸡北—岐山—泾阳一带的山区的剪应变都出现正值,这说明该区域强剪切应变带来的变形集中区可能与地震的后效相关,且与泾阳和宝鸡相继发生地震有着较好的对应关系。

英文摘要：

By analyzing the Weihe basin＇s crustal movement trends and strain field characteristics,valuable reference data for studying seismic activity in this region can be provided.Inverse distance weighting method is used to calculate the horizontal crustal strain model.The calculated point displacement function was derived by using displacement value of the observation point and the distance between the observation point and the calculated point.Furthermore,the distribution of regional strain field was obtained by derivation.The strain field of Weihe basin was analyzed with the GPS data from 1999 to 2002,The results show that Weihe basin principal strain presents spatial distribution inhomogeneity,And the strain properties of mountainous area are in extrusion state,on the contrary,the strain properties of basin are in a state of tension.Shear strain is symmetrical distribution along the Xi＇an-Lintong,shear strain is a negative value within the basin along Mazhao-Xi＇an-Lintong-Weinan a line,however shear strain is positively located in the both of the southof Tangyu and Baoji north-Qishan-Jingyang mountain area.The strong shear deformation area may be relevant to earthquake aftereffect,consistent with Baoji and Jingyang earthquake.