华北地区块体及其边界的相对运动

将华北地区各块体视为刚体．它们分别是阴山一燕山、鄂尔多斯、山西、太行、冀鲁和胶辽6个块体。将各断块上由GPS空间大地测量数据计算得到的点位速度进行平均作为块体总体平动运动速度．讨论了华北地区各块体间的相对运动。华北地区各块体间的相对运动总体量级不大．一般在4mm／a以内。阴山一燕山块体与其它块体间存在近东西向的走滑运动．与其它块体间的相对运动主要表现为边界间的张性和压性。GPS观测结果显示：华北地区各块体间的相对运动存在动态变化。

RELATIVE MOTION BETWEEN PLATES AND THEIR BOUNDARIES IN NORTH CHINA

Treated as a rigid, North China area is divided into 6 blocks:Yinshan-Yanshan, Ordos, Shanxi, Taihang, Jilu and Jiaoliao. Taking the mean velocity of each GPS site in a block as the translation velocity of the block, we studied the relative motions between the blocks and their boundaries in North China. The relative motion between the blocks of North China is not large, which is within 4 mm/a. There is strike slip between Yinshan-Yanshan and its neighboring blocks, but the relative motions between other blocks are mainly tensional or compressive. The GPS observation shows that the relative motions between the blocks in North China have dynamic variation.