柴达木盆地干柴沟—咸水泉地区中深层储集层分布规律

Reservoir distribution in the mid-deep formation of the Ganchaigou-Xianshuiquan region,Qaidam Basin

柴达木盆地干柴沟—咸水泉地区中深层油藏具有勘探程度低、岩性复杂、井网稀、纵向厚度跨度极大等特征,多年来油气勘探一直未获突破。利用岩性、电性、物性资料,采用定性特征识别,结合综合评分、层次分析和模糊综合评判等定量方法完成了储集层的识别与评价。结果表明,储集层以低孔隙度、特低渗透率的Ⅲ～Ⅳ类为主,主要分布在C3、X7、X8井一带,厚度由西北至东南逐渐减小,在C6与X8井一线东南逐渐消失。

The mid-deep reservoirs in the Ganchaigou-Xianshuiquan region of Qaidam Basin is characterized by low degree of exploration,complex lithology,sparse pattern,and big vertical thickness difference.Petroleum exploration has been expecting for a breakthrough in this region for many years.The reservoirs are identified and evaluated by using data of lithology,electrical property and physical property and employing methods of qualitative identification,composite rating,hierarchical analysis,fuzzy comprehensive evaluation,etc.The results show that the reservoirs are dominated by Class Ⅲ～Ⅳ reservoirs of low porosity and ultra-low permeability,mainly distributed along C3,X7 and X8 wells,reservoir thickness gradually decreases from northwest to southeast and pinches out to southeast along X8 and C6 wells.