CAJ | 학술논문

鄂尔多斯盆地镇北地区延长组长4＋5以成岩型低渗透储层为主，常规方法较难评价该类储层微观孔隙结构品质。利用铸体薄片、扫描电镜和物性分析等方法对影响储层微观孔隙结构特征的因素进行了定性分析，恒速压汞方法对储层微观孔隙结构特征参数进行了定量表征。研究表明：镇北地区长4＋5低渗透储层微观孔隙结构与成岩作用密切相关，主要表现为机械压实作用和碳酸盐胶结作用越弱，长石溶蚀作用越强烈，粒间孔和溶蚀孔越发育，孔喉连通性越好，渗透率越大；微观孔隙结构和渗透率受大于0．12μm的喉道控制明显，主要表现为平均喉道半径越大，渗透率越大，孔喉半径比越小，微观孔隙结构越好，储层品质因子越大，试油产液量越高，尤其当平均喉道半径小于1．60μm时。喉道是影响低渗透储层微观孔隙结构品质的主要因素。
악이다사분지진북지구연장조장4＋5이성암형저삼투저층위주，상규방법교난평개해류저층미관공극결구품질。이용주체박편、소묘전경화물성분석등방법대영향저층미관공극결구특정적인소진행료정성분석，항속압홍방법대저층미관공극결구특정삼수진행료정량표정。연구표명：진북지구장4＋5저삼투저층미관공극결구여성암작용밀절상관，주요표현위궤계압실작용화탄산염효결작용월약，장석용식작용월강렬，립간공화용식공월발육，공후련통성월호，삼투솔월대；미관공극결구화삼투솔수대우0．12μm적후도공제명현，주요표현위평균후도반경월대，삼투솔월대，공후반경비월소，미관공극결구월호，저층품질인자월대，시유산액량월고，우기당평균후도반경소우1．60μm시。후도시영향저삼투저층미관공극결구품질적주요인소。
The fourth and fifth members of the Yanchang Formation ( Chang4+5) in Zhenbei area of the Ordos Basin are low?permeability reservoirs of diagenetic origin. Conventional methods such as thin section analysis, scanning electron microscopy and physical properties determination failed to analyze the microscopic pore struc?ture of these reservoirs. We used conventional methods and applied constant rate mercury penetration to study the controlling factors to quantitatively determine microscopic pore structure. The microscopic pore structure of the Chang4+5 reservoirs was mainly impacted by diagenetic effects. When mechanical compaction and carbonate cementa?tion were weaker and feldspar dissolution was more intense, intergranular pores and dissolution pores would be more developed, resulting in better connectivity and higher permeability. Microscopic pore structure and permeability were mainly controlled by throat radius. Generally, if average throat radius was >0.12μm, permeability would be higher, the smaller the pore/throat radius ratio, the better the microscopic pore structure, the greater the reservoir quality index ( RQI) , and the higher liquid oil yield, especially when the average throat radius was <1.26μm. Throats controlled the quality of the microscopic pore structure of low permeability reservoirs.