摘要
低孔隙度低渗透率致密砂岩的微观孔隙结构复杂,精细表征存在很大困难。为了揭示致密砂岩的储集与渗流机理,提出一种基于核磁共振T2谱的三组分分解方法,该方法将岩石的核磁共振T2谱等效为球型孔隙、管型孔隙与槽型孔隙对T2贡献的加权组合。利用该方法对致密砂岩岩样进行分解,具有T2谱双峰形态的岩石以槽型孔隙占优,连通性较好;具有T2谱单峰形态的岩石以管型孔隙占优,孔隙空间以束缚孔隙为主。孔隙结构三组分分解理论有效揭示了岩石各孔隙空间的分布特征,分解结果有助于储层有效储集空间的寻找与致密储层孔隙结构的精细评价。
Abstract： The microscopic pore structure in low porosity and low permeability tight sand is very complicated, and it is difficult to be detailed. In order to reveal the mechanism of gathering and seepage in tight sands, a three-component decomposition theory has been proposed based on the NMR T2 spectrum. In this theory, the pore structure is regard as spherical pore, capillary pore and trough pore, and the total NMRT2 spectrum of the pore is regard as the weighted array of the 3 types of pore structures. Some samples of tight sand cores have been decomposed by using this theory, and the results shows： the good connective pore with bimodal Tz spectrum characteristics is dominated by trough pore, and the bad conective pore with unimodal T2 spectrum characteristics is dominated by capillary pore. This decomposition theory can effectively reveal the distribution characteristics of rock pore space, and give a new idea for pore structure＇s evaluatiorl in tight sand reservoir.
出处
《测井技术》
CAS
CSCD
北大核心
2013年第6期600-604,共5页
Well Logging Technology
基金
中央高校基本科研业务费专项资金(27R1101064A)
国家科技重大专项(2011ZX05020-008)
国家自然科学基金(41174099)
中国石油天然气集团公司科学研究与技术开发项目(2011D-4104)联合资助
关键词
关键词
核磁共振测井
T2谱
孔隙结构
三组分分解
致密砂岩
nuclear magnetic resonance logging, T2 spectrum, pore structure, three-componentdecomposition theory, tight sand
