白音查干凹陷油气成藏条件及油气分布规律

白音查干凹陷以西部次凹的西部洼陷带为该凹陷的唯一生油洼陷,有阿尔善组的上部、腾格尔组的下部和都一段三套有效烃源岩。流体势分析结果表明,该区油气的主要运移方向有5个,长期活动的断层是油气垂向运移的通道,不整合面和渗透砂体是油气侧向运移的通道;油气围绕生油洼陷分布,断裂带继承性发育的构造圈闭为主、洼陷带岩性圈闲为主以及流体势的指向控制油气横向分布,区域性生储盖组合及岩性控制油气的纵向分布,不同的地区油气分布层位不同;在断裂带找油要考虑断层两侧岩性配置的影响。

Hydrocarbon pool forming conditions and distribution regularity of Baiyinchagan sag

The Western depression at the west sub-sag,with three effective source rocks as the upper Aershan formation, the lower Tenggeer formation and the first member of Du- hongmu formation,is the unique hydrocarbon-generating depression in Baiyinchagan sag.Analytical results of fluid potential suggest that the hydrocarbon was migrated along five directions;the faults active at a long period is the verti- cal migration pathway of hydrocarbon;and the unconformi- ties and permeable sand rocks are horizontal migration path- ways.Oil and gas are surrounding the hydrocarbon-genera- ting sag in Baiyinchagan depression.The inherited structural traps are dominated in fault belts,while the lithologic traps are the main type in the depression.The horizontal distribu- tion of hydrocarbon is subject to the directions of fluid poten- tial.and the vertical distribution of hydrocarbon is subject to the source rock-reservoir-caprock assemblage and the li- thology,resulting in a different distribution horizon in differ- ent area.Attention should be paid on the lithological config- uration on both sides of fault in fracture zones.