鄂尔多斯盆地姬塬地区长2油藏低含油饱和度成因

Causes of low oil saturation for Chang 2 reservoir in Jiyuan Area of Ordos Basin

刘超威 陈世加 姚宜同 黄囿霖 张潇文

西南石油大学地球科学与技术学院，四川 成都 610500

School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China

在储层含油饱和度测试资料的基础上，结合油源、油气成藏动力、储层物性及含油性分析，明确了鄂尔多斯盆地姬塬地区长2油藏低含油饱和度的成因机理。研究表明：研究区长2储层远离下部长7烃源岩生烃中心，油源不足是姬塬地区长2油藏含油饱和度低的根本原因；由于长2油藏构造幅度低，油气运移的动力较小，而且长2储层中束缚水饱和度较高，油气难以驱替，从而使得长2油藏含油饱和度低；此外，长2储层较强的非均质性，也是长2油藏低含油饱和度的原因。

Based on the test data of oil saturation and in combination with the analysis of source rock, hydrocarbon accumulation dynamics, physical properties and oiliness of reservoir, this paper studies the formation mechanism of low oil saturation for Chang 2 reservoir in Jiyuan Area of Ordos Basin. The results show that Chang 2 reservoir is far from oil generation center and the lack of hydrocarbon source is the underlying causes of low oil saturation. Because the structure amplitude is low, the motivating force of migration is small, the irreducible water content is high and it is difficult to be displaced for oil and gas, the oil saturation of Chang 2 reservoir is low. Furthermore, the strong heterogeneity is the reason resulting in low oil saturation.

10.6056/dkyqt201503008