基于1999-2007年GPS水平速度场资料,利用块体模型和跨断层速度剖面,并结合断裂带两侧应变场的分布,分析了海原-六盘山断裂带分段及整体运动变形特征.结果表明:托莱山与冷龙岭断裂的滑动性质为走滑兼挤压；金强河断裂变形最显著,剪切应变积累程度最高；毛毛山-老虎山断裂中的毛毛山段比老虎山段应变积累大；海原断裂(狭义)左旋走滑速率为5 mm/a,海原地震至今仍以蠕滑调整为主；六盘山北段有2.4 mm/a的挤压量,其挤压应变积累相对显著,而六盘山中南段变形不明显.海原-六盘山断裂带由西向东整体呈现出走滑兼挤压-走滑-挤压的构造转换样式.%On the basis of the GPS horizontal velocity field data in the period of 1999 -2007, using the block model and GPS velocity profiles across faults and combining with the distribution of the strain rate field near it. we analyzed the present-day tectonic deformation characteristics of the Haiyuan-liupanshan fault zone from its segments and the entirety. The results show that the characteristics of the Tuolaishan fault and the Lenglongling fault is strike-slip with compression; The deformation of the Jinqianghe fault is the most distinct, and its shear strain accumulation is the highest. The strain accumulation on the Maomaoshan segment is larger than that of the Laohushan segment. The left slip rate of the special Haiyuan fault is 5 mm/a, and this fault is still creeping and adjusting since the Haiyuan earthquake occurrence. The compressive velocity across northern segment of the liupanshan fault is 2. 4 mm/a, whose compressive strain accumulation is obvious. However the deformation of middle and south segment of the liupanshan fault is not distinct. The strike slip with compression-strike slip-compression transformation pattern presentes themselevs in the entire fault system from west to east.
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