普光地区须家河组致密砂岩储层研究

发布时间：2018-03-09 22:30

本文选题：普光地区　切入点：三叠系　出处：《长江大学》2015年硕士论文　论文类型：学位论文

【摘要】：普光气田位于四川盆地东北部,北面紧邻大巴山前缘推覆构造带,面积1116km2。普光气田主体陆相位于四川盆地川东断褶带黄金口构造带普光—双石庙北东向构造带的北端,介于大巴山推覆带前缘断褶带与川中平缓褶皱带之间。本区陆相地层同四川盆地基本相似。多年的勘探开发实践表明,该区除了海相碳酸盐岩地层外,三叠统发育的陆相层系亦具有很好的勘探潜力。本论文针对普光地区陆相地层须家河组进行研究,从构造、沉积相、储层特征研究等多方面分析,深度剖析该陆相地层在油气勘探方面的潜力,并明确潜力的分布特征,对该区陆相地层的勘探具有指向性的意义。在对获取的岩心、测井、录井、分析化验数据和地震数据等多方面资料详细研究和分析,结合前人对本地区的深入研究成果,得到了一下几个方面的成果：1、本工区在须家河组沉积时期,位于东北方向的川东北大巴山造山带为本地区带来了大量的陆源碎屑,是最为主要的沉积物来源；2、须家河组沉积时期,研究区地势较为平缓,坡度不大,主要以发育浅水辫状河三角洲沉积为主。其中平原亚相是该沉积时期最为发育的亚相,分布的面积最广,厚度也最大。据划分和统计,本区须家河组共发育三种沉积亚相,共八种微相。3、通过细致的地层对比及沉积相刻画工作,须二、四、六段的沉积厚度较大,砂地比值较高,而须三、五段的沉积厚度薄,以发育泥质沉积为主,砂体比低。在各段中,须二段河道砂体最为发育,河道叠置的厚层砂体分布最广,连续性最好,其次是须四段、须六段；4、数据分析本区储层砂岩的磨圆和分选较好,结构成熟度相对较高,但成分成熟度较低,其长石、岩屑的含量略高,砂岩类型三角图显示本区主要发育长石岩屑质石英砂岩为主,其次为长石质岩屑砂岩。碎屑粒径主要为细粒及粉粒,少量中粒和粗粒砂岩。在须家河组四段底部出现有典型的河床沉积杂色砾岩出现；5、分析化验结果显示须家河组砂岩储层经受了强烈、复杂的成岩作用,其中最为典型且作用最强烈的成岩作用,表现为压实／压溶作用、胶结作用、破裂作用及溶解作用等。前两者使储层的原生孔隙受到大幅度压缩,以致原生孔隙消失不见,两者互相关联,共同损害者储层的原始物性,是研究区砂岩达到致密主要原因；而后两者则是提升储层物性的具有建设性的成岩作用,两者相辅相成,互相联系,为致密砂岩中发育优质储层提供了条件。破裂作用导致裂缝普遍分布,这是研究区最具特色的建设性的成岩作用,破裂作用产生裂缝是储层最广泛的储集空间,或成为溶蚀作用的通道,促进溶蚀作用发生与扩展,对溶蚀孔、缝的形成具有重要意义,因而溶解作用常与破裂作用相伴生。交代作用则与溶解作用混合发生,普遍发生在粘土矿物对长石和石英之间,可形成晶间孔。6、经细致研究发现须家河组岩层样品多方面特征严格符合中成岩B期—晚成岩期的岩石特征,结合前人成果明确本区须家河组地层成岩期次已达到中成岩B期,甚至部分到晚成岩期；7、本区储层成岩相类型可划分为长石溶蚀+破裂相；硅质胶结相；伊利石—方解石胶结相等三种成岩相。其中硅质胶结相、伊利石—方解石胶结相发育的地方往往物性较差,而长石溶蚀+破裂相是有利的成岩相,其所在的区域可成为油气勘探的重点；8、储层致密,物性指标显示该类储层属于致密砂岩储层。储层储集空间以次生溶孔、微裂缝为主,微孔次之；裂缝对致密砂岩储层的物性影响很大,次生溶孔的发育与裂缝有着密切的关系。裂缝发育的地方往往孔隙度和渗透率值高,是气藏发育的有利地带。而裂缝主要发在须家河组二段、四段的厚层砂体中,因此这两层是须家河组气层发育的最具潜力层位。
[Abstract]:Puguang gas field is located in the northeast of Sichuan basin, adjacent North foreland of Daba Mountain nappe tectonic belt, the main continental area of 1116km2. in Puguang gas field is located in the Sichuan basin in East Sichuan Puguang structure belt gold bruchfalten mouth - shuangshimiao NE trending tectonic belt between North Dabashan nappe belt and Sichuan bruchfalten front flattish fold belt. The continental strata in Sichuan basin with similar shows. The exploration and development practice for many years, in addition to the marine carbonate strata, three Permian continental strata development also has good exploration potential. This thesis focuses on the continental facies in Puguang area of Xujiahe formation were studied from the structure, sedimentary facies analysis. Study on reservoir characteristics and other aspects, in-depth analysis of the potential of continental strata in oil and gas exploration, and the distribution characteristics of clear potential, in the area of continental strata exploration has directional significance. In the Core, logging, logging, test data and seismic data and other aspects of detailed research and analysis, combined with previous results of research in this area, have the following several aspects: 1, this area in Xujiahe Formation sedimentary period, brought a lot of terrigenous debris is located in the northeast of the northeastern Sichuan bus orogenic belt for the region, is the main source of sediment; 2, Xujiahe Formation sedimentary period, the study area terrain is relatively flat, slope, mainly in the development of Braided River Delta in shallow water. The plain subfacies is the sedimentary period of the most developed sub facies, distribution area wide, thickness is also the largest. According to the classification and statistics, the Xujiahe Group has developed three types of sedimentary subfacies and eight microfacies.3, through detailed stratigraphic correlation and sedimentary facies characterization, two, four, six section thickness, sand ratio Higher to three, five of the thickness of thin, with the development of mud, sand ratio is low. In each segment, to sand river two most developed river stacked thick sand bodies most widely distributed, most continuous, second is to the four paragraph, paragraph six shall 4, data analysis; grinding and separation of reservoir in this area is good, the structure maturity is relatively high, but the low compositional maturity, the feldspar, lithic content is slightly higher, the sandstone type triangle shows the main development of feldspar detritus quartz sandstone, followed by feldspathic lithic sandstone detrital grain. Size are fine and powder, small grain and coarse grain sandstone of Xujiahe formation. In the four section appears at the bottom of the typical riverbed deposits have mottled conglomerate; 5, analysis of the test results show that the sandstone reservoirs of Xujiahe Formation underwent strong and complex diagenesis, one of the most typical and the most strong diagenesis as Used as compaction / pressolution, cementation, fracturing and dissolution. The primary pores of the reservoir is greatly compressed, so that the primary pores disappear, mutual relation, common original object of reservoir damage, is the main reason to dense sandstone in the study area; and the two is to enhance the constructive diagenesis, the reservoir properties of the two complement each other, contact each other, provide the conditions for the development of tight sandstone reservoir quality. Fracturing cause cracks are widely distributed, the constructive diagenesis of the study area is the most distinctive, fracturing cracks is in space the most widely used storage reservoir, or become the dissolution channel, promote the dissolution and expansion of pores, cracks has important significance to the formation, dissolution and fracturing and often associated with dissolution metasomatism. Effect of mixing that occurs commonly occur in clay minerals on feldspar and quartz, can form intergranular pore.6, after careful study found that the Xujiahe Formation in strict compliance with the characteristics of samples into late diagenetic characteristics of rock rock B, combined with previous results made clear the area Xujiahe Formation diagenetic stage time has reached the middle diagenetic stage B, or even to the late diagenetic stage; 7, the reservoir diagenetic facies can be divided into the dissolution of feldspar + rupture; siliceous cementation facies; illite calcite cementation are three types of diagenetic facies. The siliceous cementation facies, illite, calcite cementation facies. The place is often poor, and the dissolution of feldspar + rupture were the favorable diagenetic facies. The area where it can become the focus of the oil and gas exploration; 8, the tight reservoir, the physical index shows that the reservoir belongs to tight sandstone reservoir. The reservoir space is secondary pore, micro crack Micro crack, secondary; influence of cracks on the tight sandstone reservoir, secondary karst hole and cracks are closely related. Local cracks tend to high porosity and permeability values, gas reservoir is favorable for development zone. And the main cracks in Xujiahe Formation in two, thick sand body in the four, the two layer is the Xujiahe formation and development of the most promising horizon.

【学位授予单位】：长江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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