华北及其邻区块体转动模式和动力来源

Rotation Model and Dynamics of Blocks in North China and Its Adjacent Areas

块体的转动是地壳中重要的构造运动形式。根据地质、地球物理和地震活动性等资料,可将华北及其邻区划分为3个亚板块。华北亚板块可进一步细分为多个次级块体。这些不同级别的块体或多或少都显示出一定的刚体特性。根据地质构造、地震和古地磁测量等资料,详细地论述了不同级别块体的转动问题,即华北及其邻区的黑龙江、华北和华南等3个近东西向亚板块自老第三纪以来相对于新疆地区顺时针转动了1.6°～35°;华北亚板块内部北北东向的次级块体自新第三纪以来逆时针转动了1.3°～ 37°.最后探讨了这种转动的动力来源。

According to the geological, geophysical and seismic data, North China and its adjacent areas may be divided into three sub-plates, and North China sub -plate may be further divided into several blocks.These sub-plates and blocks present some rigid feature. Sub-plates and block rotations are discussed in details by the study of structural geology, seismicity and paleomagnetic measurment. Three sub-plates have clockwise rotated about 16°-3.5° since the Early Tertiary with respect to Xinjiang region. Blocks in North China have anticlockwise rotated about 1.3°-3.7° since the Late Tertiary. Finally,the dynamics of rotation is preliminarily studied.