柴达木盆地新生代成盆动力学模式

Patterns of Cenozoic sedimentary basin-forming dynamics in Qaidam Basin

应用地震勘探资料和平衡剖面恢复技术对柴达木盆地断裂特征进行了研究,并结合柴达木盆地岩石圈结构特征和区域应力场资料,对盆地新生代构造演化阶段及盆地类型进行了重新划分和确定。该盆地演化既受区域应力场及盆缘走滑断裂活动的控制,也受地壳深部活动的影响,其成盆动力学模式为深层伸展,浅层压扭。这一模式不但较好地解释了盆地的构造特征,而且较好地解释了盆地新生代沉积迁移规律,是对“大型拆离伸展—拉分盆地”成盆模式的补充与完善。

The seismic survey data and the restoring technology for profile equilibrium were applied to research the characteristics of faults in Qaidam Basin. On the basis of the lithosphere structural characteristics and the regional stress field in Qaidam Basin, the Cenozoic structural evolution stage and types of basin were redivided and determined. The result showed that the evolution of this basin was controlled by the regional stress field and breakout of margin slides and also influenced by deep activities of earth crust. The dynamic pattern was characterized by deep level extends and shallow lamination and torsion. This pattern can be used to explain the structural characteristics and Cenozoic deposition-migration rule of Qaidam Basin. It also becomes the supplement and consummation to the basin-forming pattern of the large-scale open-extending and pull-apart basins.