鄂尔多斯盆地尹陕斜坡延长组东、西成藏差异

Reservoir-Formation Differences between East and West Yanchang Formation in Ih-Ju Shaanxi Slope of Ordos Basin

鄂尔多斯盆地伊陕斜坡延长组东、西部油藏分布格局存在较大差异，东部志靖-安塞地区纵向上油藏集中分布于长6层，平面上长6油藏大面积连片分布；西部姬塬地区具有同一区块垂向多油层叠合、平面上发育多个独立含油富集区的特点。分析认为，不同的运聚成藏模式，导致了两个地区不同的油藏分布格局。主要表现在以下4个方面：（1）沉积规模不同。东部的志靖-安塞地区属于陕北复合三角洲的主体部分，沉积规模大于西部的姬塬地区。（④受沉积和成岩作用双重控制。志靖-安塞地区储层物性好于姬塬地区。③主要运移通道不同。志靖-安塞地区的主要通道是连通砂体：姬塬地区的主要通道是微裂缝．．④运聚成藏模式不同。东部志靖-安塞地区为连通砂体侧向运移的运聚模式：西部姬塬地区为裂缝垂向多点式充注的运聚模式。明确盆地伊陕斜坡东、西戍藏差异，总结石油运聚规律，对于指导盆地石油勘探部署，为勘探决策提供依据等方面均具有重要的指导意义。

There are big diffrenees between oil reservoir distribution patterns in Zhijing-Ansai region and Jiyuan tgion of eastern and western Yanchang Formation of Ih-Ju Shaanxi slope in Ordos Basin. It is considered by analysis of this paper that ditrent migration and accumulation-into-reselwoir modes caused different oil reservoir distribution patterns in the two regions. They are mainly represented on the following fonr aspects： （1） Different sedimentation scales. In the East, Zhijing- Ansai region is the main body of the composite delta of northern Shaanxi, with a larger sedimentation scale than that of the west, Jiyuan region. （2） They are controlled by both sedimentation and diagenesis. The reservoirs＂ physical property of Zt, ijing- Ansai region is better than that of Jiyuan region. （3） Different main migration paths. Main paths in Zhijing-Ansai region are inter-connected sand body, while that in Jiyuan region is micro-fractures. （4） Different migration and accumulation-into- reservoir modes. In the East, Zhijing-Ansai region, the migration and aceumulation mode is side migration through comlected sand body; while in the west, Jiyuan region, the mode is muhi-point filling through vertical fractures. Defining the differences between the eastern and western acemnulation-into-reservoir modes in the Ih-Ju Shaanxi slope of the basin and summarizing petroleum migration and accumulation law will be of important significance for guiding the petroleum exploration deployment in the basin and providing references for exploration decision-making and other aspects.