准噶尔盆地燕山运动期构造应力场模拟

Simulation of Structural Stress Field during Yanshan Movement in Jung-gar Basin.

运用有限元法的三维数值模拟程序,对准噶尔盆地燕山运动期古构造应力场进行了模拟。模拟结果表明,该期构造应力场最大主应力的高值区主要分布在盆地周边,内部应力值低;由南向北,最大应力值有由大变小的趋势。最小主应力呈带状分布,在盆地内部呈近东西向,与断层走向及主构造线基本一致。剪应力分布在盆地周边,内部剪应力小。结合石油地质资料及油气运移能力,这种应力分布有利于油气在中央隆起带、北天山山前及西部的低应力区及高应力区包围的相对低应力区聚集。

By 3D simulation procedure of limited element method,this paper presents the simulation of paleo-tectonic stress field in Junggar basin during Yanshan movement.The results show that the high value zone of the maximum principal stress in this period distributes the basinal margin with low interior stress.From south to north,the trend of the maximum principal stress changes from high to low.The mini -mum principal stress assumes zonal distribution with trend near E-W,similar to fault trend and major structural line.The shear stress mainly distributes in the basinal surroundings with low interior shear stress.Integrating available petroleum geological data and hydrocarbon migra-tion data,these stress distributions are favorable for oil/gas accumulation in the center uplift belt,low stress zone of north Tianshan mountain front and western part as well as relatively low stress zone surrounded with high stress zone in Junggar basin.