摘要
长2低电阻率油藏属非常规油气藏,识别和开发难度大,该类油气藏在鄂尔多斯盆地分布广泛。在长2低阻油藏成藏地质特征分析基础上,开展了长2低阻油藏成因分析,探索了低阻油层识别方法。研究认为:1)长2低阻油藏成藏有利区受纵向远源运移,有利沉积相带和鼻状微构造影响,同时储盖组合控制油气富集;2)远源运移造成油藏呈低含油饱和度、高矿化度地层水特征,低幅度微弱构造使油藏油水无明显边界,沉积作用、成岩作用使储层孔隙结构变差;3)研究区长2低阻油层识别方法分为4种,邻井对比定性评价法、自然电位差值法、可动水分析法和交会图法等方法识别低阻油层效果较好。研究成果对鄂尔多斯盆地长2低电阻率非常规油藏识别评价及及有利区预测具有一定的方法指导意义,同时对鄂尔多斯盆地长2非常规油气的增储开发具有积极的作用。
Chang2 low resistivity reservoir is an unconventional reservoir,which is difficult to identify and develop.It is widely distributed in Ordos Basin.Based on the analysis of reservoir forming geological characteristics of Chang2 low resistivity reservoir,the cause analysis is carried out,and the identification method of low resistivity reservoir is explored.The results show that:1)The favorable accumulation area of Chang2 low resistivity reservoir is affected by the longitudinal far source migration,favorable sedimentary facies and nasal microstructures,and the reservoir cap assemblage controls the hydrocarbon accumulation.2)The reservoir is characterized by low oil saturation and high salinity formation water due to the distant migration.The low amplitude and weak structure makes the oil and water in the reservoir have no obvious boundary,and the sedimentation and diagenesis make the reservoir pore structure deteriorate.3)There are four identification methods of low resistivity oil layer in Chang2 in the study area,including adjacent well contrast qualitative evaluation method,natural potential difference method,movable water analysis method and crossplot method.The research results have a certain guiding significance for the identification and evaluation of Chang2 unconventional oil reservoir with low resistivity and the prediction of favorable areas in Ordos Basin,and have a positive effect on the increase of Chang2 unconventional oil and gas reservoir development in Ordos Basin.
作者
刘玺
杨兴利
张珊珊
张道亮
薛金泉
LIU Xi;YANG Xingli;ZHANG Shanshan;ZHANG Daoliang;XUE Jinquan(Exploration and Development Technology Research Center, Yanchang Oil Field Co., Ltd., Shaanxi Yan’an 716000, China;Zhidan Oil Production Plant, Yanchang Oil Field Co.,Ltd., Shaanxi Yan’an 717500, China)
出处
《非常规油气》
2022年第3期52-63,共12页
Unconventional Oil & Gas
基金
国家自然科学基金项目“中国中西部地质历史时期湖相白云岩类比研究及实验模拟”(41272115)。
关键词
长2油层组
油藏成因
判识方法
志丹油田
鄂尔多斯盆地
Chang2 oil formation
reservoir genesis
identification method
Zhidan Oilfield
Ordos Basin
