川东北元坝地区须三气藏致密储层特征及分布规律研究
发布时间：2018-07-22 11:40
【摘要】：低渗透致密砂岩天然气高效勘探和开发的关键是致密储层特征及分布规律的研究评价。川东北元坝地区须三气藏储层的平均孔隙度2.33%,平均渗透率0.082md,属低渗低孔储层,而且产能受裂缝发育程度得影响。本文综合运用沉积地质学、层序地层学、矿物岩石学以及储层构型分析等理论和技术方法,对川东北元坝地区须三段沉积相及致密砂岩储层特征进行了研究,并通过储层测井响应特征对裂缝发育程度进行了评价,进而对储层主控因素及分布规律展开了深入的研究,认为：①须三气藏为辫状河三角洲沉积体系,根据岩心相、测井相、地震相结合,单井相、连井相分析,结合砂组划分,研究纵向沉积演化及砂组横向沉积微相展布,落实有利微相带,为分流河道和河口坝。②须三气藏储层极为致密,属低孔低渗储层。储层岩石类型以中粗粒钙屑砂岩、砂砾岩为主；钙屑砂岩储集空间以粒间溶孔、胶结物溶蚀孔、岩屑晶间孔和内溶孔为主,其次为粘土矿物晶间孔等；砂砾岩储集空间以微缝为主。钙屑砂岩平均孔隙度2.6%,平均渗透率0.0155md；砂砾岩平均孔隙度1.95%,平均渗透率0.0621md。③裂缝具有双重渗流作用,是储层是否有效和产能高低的关键控制因素,须三气藏整体裂缝比较发育,以构造缝为主,与断层派生缝和层间缝等综合形成网状裂缝带,但各砂组差异比较大,主要分布于1砂组的YL20-YB205井区、3砂组的YL12-YB6井区和YL7井区,含气性较好、含气砂体厚度大。④须三致密储层发育的主控地质因素与岩性、有利储层厚度以及裂缝发育程度密切相关,储层段主要岩相为中-粗粒钙屑砂岩相及砂质砾岩相；纵向上储层岩性变化较大,岩性变粗,孔隙类型及结构变差,局部有利岩性发育带和裂缝发育区,有效储层较发育。⑤须三气藏致密储层发育特征变化大,根据岩性及厚度、物性、储集空间与裂缝发育程度划分有利区和较有利区,并划分储层类型：储层以Ⅲ类储层为主,优质储层中以Ⅱ类储层为主,Ⅰ类储层较少。平面上储层主要集中在该区西部,厚度较大、含气性好,而中部及东部以含气性弱、厚度薄；4个岩性有利主河道评价潜力区主要为1砂组的YL10-YB205井区、3砂组的YL12-YB6井区和YL7井区。
[Abstract]:The key to high efficiency exploration and development of low permeability tight sandstone natural gas is the study and evaluation of tight reservoir characteristics and distribution law. The average porosity and average permeability of the reservoir are 2.33 and 0.082 mdrespectively, which belong to low permeability and low porosity reservoir, and the productivity is affected by the fracture development degree. Based on the theories and techniques of sedimentary geology, sequence stratigraphy, mineral petrology and reservoir configuration analysis, the sedimentary facies and tight sandstone reservoir characteristics of the third member in Yuanba area, northeast Sichuan are studied in this paper. The degree of fracture development is evaluated by the response characteristics of reservoir logging, and the main controlling factors and distribution law of reservoir are studied deeply. It is considered that the reservoir is a braided river delta sedimentary system, according to the core facies and logging facies, the reservoir is a braided river delta sedimentary system. The combination of seismic facies, single-well facies, multi-well facies analysis, combined with sand formation division, the study of longitudinal sedimentary evolution and the distribution of transverse sedimentary microfacies of sand formation, the implementation of favorable microfacies zone, the reservoir is extremely compact for distributary channel and estuarine dam .2 gas reservoir. It belongs to low porosity and low permeability reservoir. The reservoir rock types are mainly medium coarse calcareous sandstone, sand gravel, intergranular dissolution pore, cemented dissolution pore, lithic intergranular pore and internal dissolved pore, followed by clay mineral intergranular pore, etc. The reservoir space of calcareous sandstone is mainly composed of intergranular dissolution pore, cemented material dissolution pore, lithic intergranular pore and internal dissolved pore, etc. The microfracture is the main reservoir space of sandy gravel. The average porosity of calcareous sandstone is 2.6, the average permeability is 0.0155md, the average porosity of gravel is 1.95, and the average permeability of 0.0621md.3 fracture is double percolation, which is the key controlling factor of reservoir effectiveness and productivity. The network fracture zone is formed mainly by structural fractures, combined with fault derived fractures and interbedded fractures, but the differences among sand groups are quite great. They are mainly distributed in YL20-YB205 well area, YL20-YB205 well area, YL12-YB6 well area and YL7 well area, where the gas content is good, and the gas content of YL12-YB6 well and YL7 well area is better than that of YL20-YB205 well group. The main controlling geological factors for the development of gas-bearing sand body are closely related to lithology, favorable reservoir thickness and fracture development degree. The main lithofacies in the reservoir section are medium-coarse calcareous sandstone facies and sandy conglomerate facies. Longitudinally, reservoir lithology changes greatly, lithology becomes thicker, pore type and structure become worse, local favorable lithologic development zone and fracture development zone, effective reservoir has more development characteristics than that of developing 5. 5 gas reservoir, according to lithology and thickness, it is necessary to change the characteristics of tight reservoir in effective reservoir, according to lithology and thickness. Physical properties, reservoir space and fracture development degree are divided into favorable areas and favorable areas, and the types of reservoirs are classified as follows: type 鈪，
本文编号：2137335
[Abstract]:The key to high efficiency exploration and development of low permeability tight sandstone natural gas is the study and evaluation of tight reservoir characteristics and distribution law. The average porosity and average permeability of the reservoir are 2.33 and 0.082 mdrespectively, which belong to low permeability and low porosity reservoir, and the productivity is affected by the fracture development degree. Based on the theories and techniques of sedimentary geology, sequence stratigraphy, mineral petrology and reservoir configuration analysis, the sedimentary facies and tight sandstone reservoir characteristics of the third member in Yuanba area, northeast Sichuan are studied in this paper. The degree of fracture development is evaluated by the response characteristics of reservoir logging, and the main controlling factors and distribution law of reservoir are studied deeply. It is considered that the reservoir is a braided river delta sedimentary system, according to the core facies and logging facies, the reservoir is a braided river delta sedimentary system. The combination of seismic facies, single-well facies, multi-well facies analysis, combined with sand formation division, the study of longitudinal sedimentary evolution and the distribution of transverse sedimentary microfacies of sand formation, the implementation of favorable microfacies zone, the reservoir is extremely compact for distributary channel and estuarine dam .2 gas reservoir. It belongs to low porosity and low permeability reservoir. The reservoir rock types are mainly medium coarse calcareous sandstone, sand gravel, intergranular dissolution pore, cemented dissolution pore, lithic intergranular pore and internal dissolved pore, followed by clay mineral intergranular pore, etc. The reservoir space of calcareous sandstone is mainly composed of intergranular dissolution pore, cemented material dissolution pore, lithic intergranular pore and internal dissolved pore, etc. The microfracture is the main reservoir space of sandy gravel. The average porosity of calcareous sandstone is 2.6, the average permeability is 0.0155md, the average porosity of gravel is 1.95, and the average permeability of 0.0621md.3 fracture is double percolation, which is the key controlling factor of reservoir effectiveness and productivity. The network fracture zone is formed mainly by structural fractures, combined with fault derived fractures and interbedded fractures, but the differences among sand groups are quite great. They are mainly distributed in YL20-YB205 well area, YL20-YB205 well area, YL12-YB6 well area and YL7 well area, where the gas content is good, and the gas content of YL12-YB6 well and YL7 well area is better than that of YL20-YB205 well group. The main controlling geological factors for the development of gas-bearing sand body are closely related to lithology, favorable reservoir thickness and fracture development degree. The main lithofacies in the reservoir section are medium-coarse calcareous sandstone facies and sandy conglomerate facies. Longitudinally, reservoir lithology changes greatly, lithology becomes thicker, pore type and structure become worse, local favorable lithologic development zone and fracture development zone, effective reservoir has more development characteristics than that of developing 5. 5 gas reservoir, according to lithology and thickness, it is necessary to change the characteristics of tight reservoir in effective reservoir, according to lithology and thickness. Physical properties, reservoir space and fracture development degree are divided into favorable areas and favorable areas, and the types of reservoirs are classified as follows: type 鈪，
本文编号：2137335
本文链接：https://www.wllwen.com/kejilunwen/diqiudizhi/2137335.html
