吐哈盆地西部岩性油气藏成藏主控因素分析及分布模式

通过对吐哈盆地西部葡北-葡萄沟和红连等油田已发现油气藏的油气来源、构造位置、储层物性及砂体厚度等成藏条件进行分析,认为油源断裂、源区、与构造配置关系、物性及薄层砂体是岩性油气藏形成的主控因素,离生烃灶较远地区的成藏关键因素为油源断裂及构造翼部物性较好的薄砂层,生烃灶范围内的成藏关键因素为构造斜坡物性较好的薄砂层.据此归纳出远源断裂--砂体榆导构造翼部岩性油气藏和凹陷内砂体输导隆起斜坡岩性油气藏2种分布模式,指出葡北和红连地区向凹陷方向的上侏罗统三角洲前缘砂体及葡萄沟地区构造高部位的三间房组三角洲前缘砂体是岩性油气藏勘探的重要领域.

Control Factors and Distribution Pattern of Lithologic Hydrocarbon Reservoirs in the Western Tuha Basin

The study on the reservoir forming conditions, including hydrocarbon origin, structure location, reser-voir physical property, sand body thickness, and so on, of the discovered hydrocarbon reservoirs in the Pubei-Putaogou and Honglian oil fields in the west of Tuha basin, reveals that the sand body which approaches to the hy-drocarbon generating centre and oil sources fault, best allocation to structure, good physical property and thin thickness are the main controlling factors for the formation of lithologie hydrocarbon reservoirs. The key factors for reservoirs being far away from hydrocarbon kitchen are oil sources fault and thin and good physical property sand layer located in the limb of structure. The key factors for reservoirs in the hydrocarbon kitchen is good physical property sand layer located in the slope of structure. We summarized two lithologic hydrocarbon reservoir distribu-tion pattern that are distal-source structure limb lithologic hydrocarbon reservoir and inner-depression uplift slope lithologic hydrocarbon reservoir. The Upper Jurassic delta front sand body in the Pubei and Honglian areas, and the Sanjianfang Formation delta front sand body in high place of structure in the Putaogou area are the most impor-tant exploration targets.