塔中隆起鹰山组岩溶储层特征及主控因素

探讨塔中隆起鹰山组碳酸盐岩岩溶储层发育主控因素，为寻找鹰山组岩性油气藏提供地质理论依据。通过岩芯、薄片观察以及物性资料分析，并结合成像测井解释，认为鹰山组碳酸盐岩为低孔低渗岩溶储层，储集空间主要为溶孔、裂缝及溶洞。将中下奥陶统碳酸盐岩储集层划分为裂缝-孔隙型、裂缝型、溶蚀孔洞型及岩溶洞穴型等类型；精细刻画岩溶储层发育样式，讨论岩溶储层发育主控因素：（1）加里东期中期第I幕致使地层隆升为一个大的宽缓的背斜构造，碳酸盐岩地层普遍遭受顺层淋滤、溶蚀。构造活动的挤压褶皱及断裂作用可形成许多构造裂缝，从而在垂向上增加灰岩地层渗透性和水平方向连通性；（2）泥晶灰岩、含云灰岩、云质灰岩在岩溶过程中，岩性较为致密，只能沿裂缝发生溶蚀作用形成溶孔-扩溶缝，含灰质白云岩和灰质白云岩具有较好孔渗，使得地表水相对更容易流经白云岩地层，形成大量溶孔；（3）白云石化作用普遍提高了白云岩地层（结构好、白云石含量高）的孔渗性能，为岩溶作用提供了基础。

Karst Reservoir Characteristics and Main Controlling Factors of the Yingshan Formation in the Tarim Basin Central Uplift

The main factors controlling the development of carbonate karst reservoir of the Yingshan Formation, Tarim Basin Central Uplift are discussed here to provide a theoretical basis for exploring lithological hydrocarbon reservoir traps of the Yingshan Formation. Results of rock core and thin section observation and physical data analysis, along with borehole imaging interpretation suggest that the carbonate rocks of the Yingshan Formation form a low-porosity, low-permeability karst reservoir. The reservoir space mainly comprises dissolution pores, fractures, and dissolution cavities. The mid-lower Ordovician carbonate reservoir is classified into several types such as fracture-pore, fracture, dissolution pore, and karst cavity. The development process of the karst reservoir is described in detail, and the factors controlling the development are also discussed:(1) mid-Caledonian phase I led to the uplift of rock layers and formation of a broad anticline structure. Carbonate rocks generally experienced leaching and corrosion parallel to the strata. Extrusion fold and faulting from tectonic activities formed numerous structural fractures, resulting in increased vertical permeability and horizontal connectivity of the limestone strata; (2) micritic limestone, dolomite-containing limestone, and dolomitic limestone are more compact lithologically, and only corroded along fractures to form dissolution pores-expanded dissolution cracks during the karst process. Limestone-containing dolomite and calcite dolomite have good porosity and permeability, and a section of the underlying dolomite strata is exposed to the surface. This enabled surface water to easily flow through dolomite strata, thereby forming a large number of pores; (3) dolomitization in general enhances the porosity and permeability of the dolomite strata (due to favorable structure and high dolomite content), providing the basis for the karst process.