中国塔里木地块的视极移曲线

APPARENT POLAR WANDER PATH OF THE TARIM MASSIF IN CHINA

塔里木地块的视极移曲线由泥盆纪,晚石炭世,二叠纪,早三叠世和侏罗-白垩纪古地磁极联线构成。(D:P_(lat)=16,P_(long)=165,A_(95)=4;C_3:P_(lat)=41,P_(long)=160,A_(95)=4;P:P_(lat)=61,P_(long)=177,A_(95)=9;T_3:P_(lat)=69,P_(long)=183,A_(95)=11;J-K:P_(lat)=65,P_(long)=214,A_(95)=6)根据古地磁研究,塔里木地块在泥盆和二叠纪之间俯冲到哈萨克斯坦地块之下。塔里木,华北和华南的缝合年代在早三叠世和早白垩世之间,相对于西伯利亚,塔里木地块自白垩纪之后有较大的东向运动。

The APW path of the Tarim massif consists of geomagnetic poles of the Devonian, Late Carboniferous, Permian, Early Triassic and Jurassic-Cretaceous (D:P_(lat) = 16,P_(long)= 165A_(95_=4,K=29: C_3:P_(lat)= 41,P_(long)= 160,A_(95)= 4,k=823;P:P_(lat)= 61, P_(long)= 177,A_(95) = 9,K = 98;T_3:P_(lat)= 69,P_(long) = 183,A_(95) = 11 ; J—K:P_(lat)= 65,P_(long)= 214, A_(95)=6, K = 66). Based on the APW path it is concluded that the plate of the Tarim massif was subducted beneath the Kasakstan massif between the Devonian and Permian. This process was basically ended by the end of the Permian. The Early Triassic poles of the Tarim, North China, South China and Siberia massifs were different from each other, suggesting the existance of post-Early Triassic relative motion among them, whereas the Cretaceous poles of them were consistent, indicating that no significant relative motion existed among them after the Creta ceous. The APW path of the Tarim massif is similar in form to that of the Siberia massif, except that the former systematically deviates to the east relative to the latter. To make these two paths overlap, one must rotate the former clockwise for 26° about the Euler pole at 14°E and 60°N, with respect to the latter. Tectonically, it means that the Tarim massif moved for about 2000km eastward with respect to the fixed Siberia massif.