Lithospheric structure and dynamic processes of the Tianshan orogenic belt and the Junggar basin

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• 作者：Junmeng ; Zhao ; Guodong ; Liu ; Zaoxun ; Lu ; Xiankang ; Zhang ; Guoze ; Zhao
• 关键词：Tianshan orogenic belt ; Junggar basin ; Lithospheric structure ; Velocity structure ; Wavelet transform
• 刊名：Tectonophysics
• 出版年：2003
• 出版时间：December 4, 2003
• 年：2003
• 卷：376
• 期：3-4
• 页码：199-239
• 全文大小：5.50 M

文摘

Located at the center of the Eurasian continent and accommodating as much as 44 % of the present crustal shortening between India and Siberia, the Tianshan orogenic belt (TOB) is one of the youngest (<20 Ma) and highest (elevation>7000 m) orogenic belts in the world. It provides a natural laboratory for examining the processes of intracontinental deformation. In recent years, wide angle seismic reflection/refraction profiling and magnetotelluric sounding surveys have been carried out along a geoscience transect which extends northeastward from Xayar at the northern margin of the Tarim basin (TB), through the Tianshan orogenic belt and the Junggar basin (JB), to Burjing at the southern piedmont of the Altay Mountain. We have also obtained the 2D density structure of the crust and upper mantle of this area by using the Bouguer anomaly data of Northwestern Xinjiang. With these surveys, we attempt to image the 2D velocity and the 2D electric structure of the crust and upper mantle beneath the Tianshan orogenic belt and the Junggar basin. In order to obtain the small-scale structure of the crust–mantle transitional zone of the study area, the wavelet transform method is applied to the seismic wide angle reflection/refraction data. Combining our survey results with heat flow and other geological data, we propose a model that interprets the deep processes beneath the Tianshan orogenic belt and the Junggar basin.