【摘要】 贝尔凹陷是海拉尔盆地中南部一个重要的早白垩世伸展断陷,受早期伸展作用和后期张扭作用的影响,走滑断层非常发育。利用地震剖面、时间切片等资料,首先分析了贝尔凹陷走滑断层的典型构造特征,由此识别出3组主要的走滑断层。然后探讨了贝尔凹陷走滑断层的成因机制,认为其发育受到早期基底伸展断层和后期张扭应力场的双重控制。在此基础上,提出了贝尔凹陷北部纯剪旋转、中南部单剪非旋转的走滑断层发育模式,即贝尔凹陷北部霍多莫尔地区发生岩石纯剪切变形,发育北东向和北北西向的共轭走滑断层,形成走滑旋转构造,而贝尔凹陷中南部的苏德尔特地区和敖脑海地区则发生岩石简单剪切变形,发育北东东向走滑断层。贝尔凹陷走滑断层可以提供有效圈闭并改善储层物性,有助于油气成藏。更多还原

【Abstract】 Beier sag is an important Early Cretaceous rift sag in the south of Hailaer basin.Owing to the early structural extension and the late structural transtension,the strike-slip faults are developed in the Beier sag.By means of seismic profiles and time slices,we describe the typical structural characteristics of strike-slip faults,identify three groups of major strike-slip faults,and then discuss the genesis of strike-slip faults in the Beier sag.The development of these strike-slip faults are controlled by both early extension basement faults and late transtension stress field.We give two patterns for the development of strike-slip faults in the Beier sag;one is pure shear and strike-slip rotation in the north and the other is simple shear and non-rotation in the central and south.The rock deformation caused the pure shear in the Huodomoer district of northern Beier sag,and produced a pair of conjugated strike-slip faults in the NE and NNE directions,respectively.The conjugated strike slip faults made the so-called"strike-slip rotation" structure.On the other hand,the rock deformation made the simple shear in both Suderte district and Aonaohai district of central southern Beier sag,and formed the north east eastward strike-slip faults.The strike-slip faults are able to not only form the effective traps,but also improve the porosity and permeability of reservoir beds.Therefore,it is profitable to conduce to the formation of petroleum reservoir.更多还原