【摘要】 致密储层微观孔喉结构特征不同导致其渗流能力不同，其对应开发策略也有所不同。本文以鄂尔多斯盆地姬塬地区长6储层为例，利用铸体薄片、扫描电镜、恒速压汞、核磁共振、计算机断层扫描（CT）等分析测试手段对致密储层孔喉结构、连通性、流体可动性等进行综合分析，利用岩心多相渗流实验和真实岩心可视化微观渗流实验对不同类型孔喉结构的渗流特征进行研究。结果表明：姬塬地区长6储层平均孔隙度为12.1%,平均渗透率为0.48×10^-3 μm²,储层孔隙类型以粒间孔为主，长石溶孔次之，并伴有少量晶间孔及岩屑溶孔发育。根据储层物性及孔喉结构特征将长6储层孔喉结构类型分为3类，其中Ⅰ类以粒间孔为主、长石溶孔为辅，孔隙发育且喉道间连通性好，可动空间发育，微观渗流以均匀状为主；Ⅱ类仍以粒间孔为主、长石溶孔次之，但Ⅱ类储层粒间孔比例降低，溶孔比例增加，且孔隙喉道半径较Ⅰ类减小，连通的孔隙结构空间稀疏簇状相接，可动空间较发育，微观渗流以网状为主；Ⅲ类储层孔隙类型以长石溶孔为主，其次为粒间孔，晶间孔比例增加，有效孔隙储集空间的喉道连通性较差，三维孔隙结构空间观察到其具有较强的非均质性，可动空间不发育，微观渗流以指状为主。通过宏观渗流方式与微观孔喉结构之间的综合分析表明，储层物性、孔喉组合方式及喉道发育程度决定了不同类型的渗流方式，物性较好且喉道发育的储层具有更好的水驱效果，从而具有更高的最终采收效率。更多还原

【Abstract】 The different micro pore throat structure characteristics of tight reservoirs lead to different permeability and corresponding development strategies. Taking the Chang 6 reservoir in the Jiyuan area of the Ordos basin as an example, this study comprehensively analyzes the pore throat structure, connectivity, and fluid mobility of the tight reservoir using analysis and testing methods such as casting thin sections, scanning electron microscopy, constant velocity mercury injection, nuclear magnetic resonance, and computed tomography（CT）. The study also uses core multiphase permeability experiments and real core visualization microscopic permeability experiments to study the permeability characteristics of different types of pore throat structures. Research has shown that the average porosity of the Chang 6 reservoir in the Jiyuan area is 12.1%, with an average permeability of 0.48×10^-3μm². The reservoir pore types are mainly intergranular pores, followed by feldspar dissolution pores, and are accompanied by a small amount of intercrystal pores and rock debris dissolution pores. According to the physical properties and pore throat structure characteristics of the reservoir, the pore throat structure types of the Chang 6 reservoir can be divided into three categories. Among them, Type Ⅰ is mainly composed of intergranular pores, supplemented by feldspar dissolution pores, with well-developed pores and good connectivity between throats. The movable space is developed, and the microseepage is mainly uniform. Type Ⅱ reservoirs are still dominated by intergranular pores, followed by feldspar dissolution pores. However, the proportion of intergranular pores in Type Ⅱ reservoirs decreases, while the proportion of dissolution pores increases, and the pore throat radius decreases compared to Type Ⅰ reservoirs. The connected pore structures are sparsely clustered and connected, with more developed movable spaces. Microseepage is mainly network-like. The pore types of Type Ⅲ reservoirs are mainly feldspar dissolution pores, followed by intergranular pores. The proportion of intercrystal pores increases, and the throat connectivity between effective pore reservoirs is poor. The three-dimensional pore structure space shows strong heterogeneity, and the movable space is not developed. Microseepage is mainly finger-shaped. The comprehensive analysis between macroseepage methods and microscopic pore throat structures shows that reservoir physical properties, pore throat combination methods, and degree of throat development determine different types of seepage methods. Reservoirs with good physical properties and well-developed throats have better water flooding effects, thereby improving the final recovery efficiency.更多还原