新场须五段致密气储层微观结构研究

发布时间：2018-06-04 02:30

本文选题：须五段 + 致密气藏　；参考：《中国地质大学(北京)》2015年硕士论文

【摘要】：本文对新场地区须五段含气储层微观结构进行系统研究,通过野外露头、岩芯及测井资料的综合分析,须五段的岩性主要为致密砂岩、粉砂岩及泥岩,发育砂夹泥、泥夹砂和砂泥岩三种组合类型,具有陆相煤系地层有机质类型及热演化特点。通过对其沉积相划分,采集不同沉积相的样品,采用偏光显微镜、扫描电镜、激光共聚焦、纳米CT扫描等技术刻画砂岩和泥岩微观结构特征,用常规的手段测试须五段砂泥岩的物性,揭示须五段主要为超致密低-超低渗储层。须五段砂岩储集空间主要有溶蚀孔、晶间孔、有机质孔和部分微裂缝,泥岩储集空间主要有矿物溶蚀孔隙、粘土矿物晶间孔、晶内孔和机质纳米孔,储集空间在有机质比较发育的层段,孔隙的连通性比较好,而其相对孤立的孔隙在空间不能够形成有效的连通。储集性能较好发育在须五段上亚段和下亚段。须五段的成岩作用主要有破坏性作用的压实作用、胶结作用,及建设性作用的溶蚀作用和破裂作用,目前主要处于中成岩A期,部分进入B期。综合分析须五段沉积相和微观结构特征提出须五段储集空间发育的主控因素,认为分流河道和河口坝是须五段致密气发育的有利储集相带,砂层与高碳泥岩配置是致密气藏高产条件,富砂型的岩性组合为须五段提供了主要的储集空间,脆性矿物及砂泥岩互层决定了储层的可压裂性能。长石、方解石及岩屑等不稳定碎屑颗粒在一定程度上阻止了成岩早-中期的压实、压溶作用,溶蚀改造作用造成了多种类型的次生溶蚀孔隙,是低孔渗背景下优质储层发育的重要因素。将须五段划分为三类储集相带:I类区,高能优势相带内、优质砂体厚度大、微裂缝发育、富含有机质、含气性好,水下分流河道砂体为骨架砂体,建设性成岩作用发育;II类区,高能优势相带内、优质砂体厚度较大、裂缝较发育、有机质含量较高,水下分流河道砂体河口坝砂体为骨架砂体,有一定的含气性;III类区,砂体累计厚度大、裂缝较发育,湖相滩坝砂体为主,有一定的含气潜力。
[Abstract]:In this paper, the microstructures of five sections of gas bearing reservoirs in Xinchang area are systematically studied. Through the comprehensive analysis of field outcrop, core and log data, the lithology of the five segments is mainly composed of tight sandstone, siltstone and mudstone, and three combinations of sand sandwiched mud, mud grit and sand mudstone, with the organic matter type and thermal evolution of the continental coal strata. By dividing the sedimentary facies and collecting the samples of different sedimentary facies, using polarizing microscope, scanning electron microscope, laser confocal and nano CT scanning, the microstructural characteristics of sandstone and mudstone are characterized, and the physical properties of the five sections of sand mudstone are tested by conventional means, and the five sections are mainly super compact low ultra low permeability reservoirs. Five sections of sandstone are required. There are mainly dissolved pores, intergranular pores, organic pores and some micro cracks in the reservoir space. The reservoir space of the mudstone is mainly composed of mineral dissolution pores, intergranular pores of clay minerals, intragranular pores and nano pores, and the reservoir space is relatively well developed in the organic matter, and the relative isolation of pores can not be effective in space. The reservoir performance is well developed in the upper and lower subsections of the upper five segments. The diagenesis of the five sections is mainly composed of the compaction, cementation, and the dissolution and rupture of the constructive action. At present, it is mainly in the A period of the middle diagenesis and part of the B period. The comprehensive analysis must be characterized by five sections of sedimentary and microstructural features. The main controlling factors for the development of the five segment reservoir space are that the distributary channel and estuarine dam are favorable reservoir facies belts for the development of dense gas in the five segments, and the sand and high carbon mudstones are the high yield conditions for the dense gas reservoirs. The lithologic combination of the rich sand type provides the main reservoir space for the five segments, and the brittle minerals and the sand mudstone interbeds determine the reservoir. Fracture properties. The unstable debris particles such as feldspar, calcite and rock debris, to a certain extent, prevent the early and middle stage compaction of diagenesis, pressure dissolution and corrosion modification have resulted in a variety of types of secondary dissolution pores, which are important factors for the development of high quality reservoirs under low porosity and permeability background. The five segments are divided into three types of reservoir facies belts: high energy area and high energy In the dominant facies belt, high quality sand body thickness, micro fissure development, rich organic matter, good gas content, underwater distributary channel sand body as skeleton sand body, constructive diagenesis, high quality sand body thickness, high quality sand body thickness, high organic matter content and sand body of underwater distributary channel estuary dam as skeleton sand body in II area There is a certain degree of gas bearing; in the area III, the sand body is thicker, the fractures are more developed, and the beach bar sand bodies are the main types of lakes, with certain gas potential.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

【参考文献】