库车坳陷北部阿合组致密砂岩储层特征及主控因素

为揭示库车坳陷下侏罗统致密砂岩储层微孔隙的成因和分布规律，通过薄片分析、扫描电镜、X射线衍射、微米CT扫描、激光共聚焦显微观察等观测手段研究北部构造带内阿合组储层特征。结果表明：微孔隙赋存于塑性矿物，其在平面和垂向上的发育明显受层段压实效应制约，构造应力、埋藏深度均是影响平面压实效应的主要因素，泥质含量是影响垂向压实效应的主要因素。阿合组致密砂岩的微孔隙由黏土矿物晶间微孔隙和杂基微弱溶蚀形成的微孔隙组成。受泥质含量、埋藏深度和构造应力的控制，微孔隙主要发育在泥质含量较低的阿合组二段，分布在埋深浅、构造应力较小的依南4井区。这对形成深部致密气藏具有重要意义。

Characteristics and main controlling factors of tight sandstone reservoir of Ahe Formation in northern Kuqa Depression

In order to reveal the genesis and distribution of micropores in the Lower Jurassic tight sandstone reservoirs in Kuqa Depression,the reservoir characteristics of Ahe Formation in northern tectonic belt were studied by means of thin section analysis,scanning electron microscopy,X-ray diffraction,micro-CT scanning and laser confocal microscopy. The results show that micropores occur in plastic minerals,and their development in the plane and vertical direction is obviously restricted by the compaction effect of intervals. Tectonic stress and burial depth are the main factors affecting the plane compaction effect,and shale content is the main factor affecting the vertical compaction effect. The micropores of the tight sandstone of Ahe Formation are composed of intercrystalline micro-pores of clay minerals and weak dissolved pores in muddy matrix. Controlled by shale content,burial depth and tectonic stress,micropores are mainly developed in the second section of Ahe Formation with low shale content,and distributed in Yinan 4 well area with shallow burial depth and small tectonic stress. This is of great significance for the formation of deep tight gas reservoirs.