Paleomagnetic study on the Cenozoic volcanic rocks from the Tuoyun Basin of the southwest Tien Shan indicates that most samples could isolate a stable character- istic remanent magnetization with reversed polarity. Th...Paleomagnetic study on the Cenozoic volcanic rocks from the Tuoyun Basin of the southwest Tien Shan indicates that most samples could isolate a stable character- istic remanent magnetization with reversed polarity. The positive fold test suggests that the characteristic component is very likely to be a primary magnetization acquired in the formation of rocks. Comparison with the reference Eurasia poles at 60 Ma indicates little or insignificant N-S conver- gence between the south edge of southwest Tien Shan and Siberia since the onset of the India/Asia collision at the Eo- cene. Furthermore, the Cretaceous and Tertiary paleomag- netic results suggest that the Tuoyun Basin was subjected to a local clockwise rotation of 20°—35° with respect to Eurasia since the Paleocene time, which is probably subsequent to the Cenozoic northward compression of the Pamir arc.展开更多
文摘Paleomagnetic study on the Cenozoic volcanic rocks from the Tuoyun Basin of the southwest Tien Shan indicates that most samples could isolate a stable character- istic remanent magnetization with reversed polarity. The positive fold test suggests that the characteristic component is very likely to be a primary magnetization acquired in the formation of rocks. Comparison with the reference Eurasia poles at 60 Ma indicates little or insignificant N-S conver- gence between the south edge of southwest Tien Shan and Siberia since the onset of the India/Asia collision at the Eo- cene. Furthermore, the Cretaceous and Tertiary paleomag- netic results suggest that the Tuoyun Basin was subjected to a local clockwise rotation of 20°—35° with respect to Eurasia since the Paleocene time, which is probably subsequent to the Cenozoic northward compression of the Pamir arc.
