依据岩心、镜下薄片、扫描电镜、阴极发光、常规和偶极子声波测井等资料，对塔中北坡柯坪塔格组的裂缝发育特征及其成藏意义进行了剖析。认为研究区内发育大量构造裂缝，裂缝产状以高角度裂缝和垂直裂缝为主，裂缝具有“密度低、长度长、宽度中等、充填低”的特征，并沿泥砾边缘、层间等岩石相对薄弱带裂缝更为发育；常规测井曲线响应特征表现为“两高、一幅度差”的特征；偶极子声波快横波各向异性和构造分析表明，裂缝的发育应与北东向走滑断裂带和NE－SW向的最大水平主应力分布有关。柯坪塔格组裂缝不仅能有效弥补致密砂岩储层物性差的不足，改善储层储渗性能，而且大尺度、高角度或垂直裂缝可作为油气垂向运移的重要通道，提高油气输导性能，是致密砂岩油气藏形成的关键要素之一。小尺度、低角度或水平裂缝是油气小规模运移调整的重要介质。%Based on the data of core, microscope thin section, scanning electron microscope, cathode lumine⁃scence, and conventional and dipole acoustic logging, the development characteristics and hydrocarbon accumula⁃tion significance of fractures in the Lower Silurian Kalpintag Formation on the northern slope of the central Tarim Basin were studied. A large number of mainly high⁃angle or vertical fractures developed in the study area. They fea⁃ture low density, long length, medium width and low filling extent. More fractures were found in the relatively weak bands of rock, such as the margins and interlayers of boulder clays. Conventional logging curves showed two peaks and one order of magnitude difference. The anisotropy of fast shear wave in dipole acoustic logging showed that fracture development was influenced by NE trending strike-slip faults and the NE-SW trending maximum horizon⁃tal principal stress. The fractures in the Kalpintag Formation played important roles in the formation of tight sand⁃stone reservoirs. They improved the porosity and permeability of tight sandstones, and the large⁃scale, high⁃angle or vertical fractures served as pathways for vertical migration of hydrocarbons. For the small⁃scale adjustment of hydrocarbon migration, the small⁃scale, low⁃angle or horizontal fractures were important.
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