鄂尔多斯盆地延长组地层水水型与油藏保存条件关系分析  

Analysis of relationship between formation water types and reservoir preservation conditions of Yanchang Formation, Ordos Basin

作　　者：齐亚林[1,2] 时孜伟[1,2] 邓静[1,2] 王亚玲[1,2] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院 [2]低渗透油气田勘探开发国家工程实验室

出　　处：《低渗透油气田》2014年第2期6-11,共6页

摘　　要：分析地层水的特征及来源对于揭示成藏机理、确定保存备件、判断油藏类型和分布规律以及评价试油结果至关重要，以长7油层组为例．系统论述了地层水化学组成特征和水型构成．综合应用有机地球化学、核磁录井等油层评价手段对基于苏林成因分类方案确定的保存条件进行分析，借鉴了水文地质学和水文地球化学的研究成果，论证了延长组地层水水型的控制因素及其与油藏保存条件的关系。研究认为：沉积水体化学组成和盐类溶解度共同控制了水型，而水型控制了矿化度：原生沉积水和后期局部可能存在的地表渗入水共同控制了地层水的离子组成及水型分布：NaHCO3型地层水和Na2SO4型地层水可能反映较差的保存条件，但并不代表油藏保存条件必然差，MgCl2型地层水和CaCl4型地层水也不代表保存条件必然好。苏林的地层水成因分类方案在确定油藏保存条件时存在一定局限性。It is enwial to analyze the characteristics and sourees of formation water for revealing the SRCA mechanism, determining pre, servation conditions, judging the oil reservoir types and distribution law, and evaluating results of lestiug for oil. Taking the Chang-7 oil resenir grnup as an example, the chemical composition features and tile water type composition are systematically discussed in the paper. The preservaliun eonditions determined on the basis of the Schulin （B.A.IKYfIHH） genetic classification seheme are analyzed by comprehensive application of oil reservoir evaluation measures of organic geochemistry and nuclear magnetic resonanee （NMR） mud logging. Taking the researeh results of hydrogeology and hydrology gen- ehemistry for reference, and demonstrated the relationship of the control fhctors of Yanchang Formation water type and the preservation comlition of oil reservoirs. The study shows that： the chemical composition of sedimentary water body and lhe solubility of salt jointly control the water type, which controls the mineralization of water. The connate sedimentary water and the local surface infiltration water that may existed in the later stage co-con- trol the ionic eompositiun and the water distribution of formation water, the formatiml water NaHC03 and Na2SO4 may reileet the poor storage condition, but not represents the inevitability, and the formation water MgCl2 and CaCl2 also can＇t certainly mean the good preservation condition. There are some limitations for Schulin genetic classification scheme of formation water when determining the oil reservoirs preservation conditions.

关 键 词：原生沉积水 地层水类型 保存条件 延长组 鄂尔多斯盆地 

分 类 号：P618.130.2[天文地球—矿床学]