松辽盆地南部让53致密区扶余油层储层特征研究

发布时间：2018-05-19 10:38

本文选题：让53致密区 + 岩石学特征　；参考：《长江大学》2015年硕士论文

【摘要】：让53致密区位于松辽盆地南部中央坳陷区长岭凹陷中部,北东接两井构造、北西为乾215井区,西南邻乾安构造,区域上为向西南倾的斜坡带,是吉林油田致密油气勘探开发的重点区域之一。研究区区域面积约260km2,共有52口井,目的层段为泉四段(K1q‘)的扶余油层。随着油田勘探开发程度不断加深,越来越多的地质问题诸如储层特征不清、储层主控因素不明等逐步暴露出来。针对研究区所存在的问题,本文立足于沉积学、石油地质学等基础理论,以高精度层序地层学等为指导,建立了精细的等时地层格架；依托于周围密井区资料,从点-线-面深入研究储层沉积微相特征,并运用沉积体系分析等理论开展沉积微相平剖面分布特征及空间演化规律研究；在此基础上,结合测井、钻录井、岩心样品的分析测试数据等资料,从泉四段储层岩石学特征、成岩作用、微观孔隙结构及储层物性特征等方面展开研究,明确储层特征,并运用定性与定量方法对储层进行评价,合理预测有利区,为研究区有效储层分布范围落实及精细油藏评价提供理论依据。依据测井资料综合解释和岩心观察,运用高分辨率层序地层学与岩石地层学等理论,把握点-线-面三位一体的整体思路,从标准井出发开展小层划分与对比工作,建立了研究区52口井目的层段内的精细地层格架,即4个砂组13个小层的地层体系,为后续储层的研究奠定了基础。根据测井曲线特征、取心井的岩心观察和粒度分析等,结合区域沉积背景,借助于周围密井区资料,开展沉积相研究,结果表明研究区总体为辫状河三角洲沉积体系,其物源主要来自于西南的通榆-保康水系,并受东南部怀德-长春水系弱影响。在这个沉积体系里主要发育三角洲平原和三角洲前缘两个亚相,三角洲平原亚相又以分流河道、分流间湾、漫溢砂和决口扇等微相发育为主,三角洲前缘亚相则主要发育水下分流间湾、水下分流河道、席状砂和河口坝等微相。Ⅳ砂组为高能远岸三角洲平原,III砂组发育低能远岸三角洲平原,II砂组发育近岸三角洲平原,I砂组则为三角洲前缘。依据研究区普通薄片、铸体薄片、扫描电镜等分析化验资料,从成分和结构两方面研究储层岩石学特征,同时对储层成岩作用进行了深入细致的分析。结果表明,研究区泉四段砂岩主要为长石砂岩、长石质岩屑砂岩和岩屑质长石砂岩,分选中等-好,颗粒接触关系以线接触为主,磨圆主要为次棱角状；储层填隙物中杂基成分主要是泥质及泥晶灰质；胶结物普遍发育,主要有：方解石、自生石英、长石加大等,胶结类型以孔隙式胶结为主。研究区泉四段储层整体处于中成岩A阶段,经历了一系列的成岩作用,其中压实作用、胶结作用、交代作用均降低砂岩储集体的原生孔隙,导致物性变差；而溶蚀作用虽利于次生孔隙的生成,但溶蚀程度较弱,不足以改善储层物性。通过分析铸体薄片、普通薄片和扫描电镜等资料显示研究区孔隙类型为原生粒间剩余孔、粒间溶孔、长石溶孔、岩屑溶孔、铸模孔、微裂隙等六种,其中原生粒间剩余孔发育较少,以粒间溶孔为主。孔隙组合类型主要为粒间溶孔一粒内溶孔。喉道类型有孔隙缩小型喉道、片状或弯片状喉道和微喉道三类,主要发育弯片状喉道和微喉道两种类型。根据压汞资料,在对孔隙结构参数分布情况和毛管压力曲线特征的分析基础上,将研究区孔隙结构分为四类：Ⅰ类为低孔细喉,为较好有效储层；Ⅱ类为低-特低孔微细喉,为一般有效储层；Ⅲ类为特低孔微细喉,经改造可以形成工业油流；Ⅳ类为特低-超低孔微细喉,基本为无效储层。研究区储层孔隙结构复杂,中值半径偏小,排驱压力相对较高,退汞效率低,最大进汞饱和度高,多偏略粗歪度,储油性能相对较好,但岩石总孔隙度中有效孔隙度较低,储层渗流能力差。通过研究表明：研究区泉四段储层整体孔隙度以低孔-特低孔为主,渗透率以超低渗为主；研究区储层的颗粒组份、沉积(微相)和胶结物类型为储层物性的主控因素；早期充分压实作用和中期岩屑等颗粒普遍黏土化、硅化成岩,很大程度降低了原生孔隙；后期碳酸盐胶结物的孔隙式胶结进一步阻塞孔隙及孔隙间的连通,降低储层物性；溶蚀作用虽有利于次生孔隙发育,但强度较弱,意义不大,储层总体致密化。针对储层的综合性能,选用岩性(粒度、成分、泥质含量)、物性(孔隙度、渗透率)、孔隙结构(孔喉中值半径、排驱压力)、成岩相、含油性(含油饱和度)、有效厚度及试油日产等参数作为储层综合评价的特征参数,对研究区储层进行综合评价,并分为一类、二类、三类、四类。研究区目的层以四类储层为主,占34.21%,三类储层次之,占30.14%,一类、二类储层所占比例相近,分别为17.68%、17.97%。其中,Ⅱ、Ⅲ砂组储层综合类型最好,I砂组次之,Ⅳ砂组储层综合类型最差；一类储层综合类型在Ⅲ砂组最为发育,所占比例为19.10%；二类储层综合类型在Ⅲ砂组最为发育,所占比例为22.47%；三类储层综合类型在Ⅰ砂组最为发育,所占比例为31.78%；四类储层综合类型在Ⅳ砂组最为发育,所占比例为43.24%。综合沉积相特征、油气成藏规律及储层综合评价结果对研究区进行有利勘探区筛选,将储层有利区分为一、二、三类：其中一类最优,二类次之,三类一般。
[Abstract]:The 53 dense area is located in the central Changling depression in the southern central depression of the Songliao Basin, the north east of the two well structure, the west to the dry 215 well, the southwest adjacent to the Qian an structure and the south-west slope zone, which is one of the key areas in the exploration and development of the dense oil and gas in the Jilin oilfield. The area of the study area is about 260km2, with a total of 52 wells. The target section is the target zone. The Fuyu oil layer of the four section of the spring (K1q). With the deepened exploration and development of the oilfield, more and more geological problems such as reservoir characteristics are not clear, and the main controlling factors of the reservoir are gradually exposed. In view of the problems existing in the study area, this paper is based on the basic theory of sedimentology, petroleum geology and so on, with high precision sequence stratigraphy, etc. A fine isochronous stratigraphic framework is set up. Based on the data of the surrounding well area, the characteristics of the sedimentary microfacies of the reservoir are deeply studied from the point to line surface, and the characteristics of the flat profile distribution and the spatial evolution of the sedimentary microfacies are carried out by the theory of sedimentary system analysis. On this basis, the analysis and testing of the samples of the logging, drilling and core are combined with the theory of logging. Data such as data, such as petrological characteristics, diagenesis, micropore structure and physical properties of reservoir in the four section of the spring, clarify the reservoir characteristics, and use qualitative and quantitative methods to evaluate the reservoir, reasonably predict the favorable area, and provide a theoretical basis for the implementation of the effective reservoir distribution and the fine reservoir evaluation in the study area. Based on the comprehensive interpretation of well logging data and core observation, using the theory of high resolution sequence stratigraphy and rock stratigraphy, the whole idea of the trinity of point line and surface is grasped, the small layer division and contrast work is carried out from the standard well, and the fine stratigraphic framework within the target layer of the 52 wells in the study area is established, that is, the land of the 13 small layers of the 4 sand groups. The layer system has laid the foundation for the study of the subsequent reservoir. According to the characteristics of the logging curve, the core observation and grain size analysis of the core well, combined with the sedimentary background of the region, the sedimentary facies study is carried out with the aid of the data of the surrounding well area. The results show that the study area is generally a braided river delta depositional system, and its source is mainly from the Tongyu in the southwest. Baokang water system is affected by the weak influence of the huild Changchun water system in the southeast. In this depositional system, the delta plain and the delta front are mainly developed in two subfacies. The delta plain subfacies mainly consists of distributary channel, inter distributary Bay, overflow sand and crevasse fan, while the delta front subfacies mainly develops underwater distributary Bay and subaqueous subdivision. III sand group developed low energy and far shore delta plain, II sand group developed near shore delta plain, and I sand group was a delta front. According to the analysis of ordinary thin slices, cast thin slices and scanning electron microscope, the two aspects of composition and structure were studied. The reservoir petrological characteristics and reservoir diagenesis are analyzed in detail. The results show that the sandstone in the four section of the spring of the study area is mainly feldspar sandstone, feldspar sandstone and lithic feldspar sandstone, and the separation of sandstone and lithic feldspar sandstone is medium good, the contact relation of the particles is mainly line contact, the grinding circle is mainly the sub angle angle, and the clutter in the reservoir filling material is complex. Mainly mud and muddy gray matter, the cementation is widely developed, mainly: calcite, authigenic quartz, feldspar and so on, and the cementation type is mainly porous cementation. The reservoir of the four section of the study area is in the A stage of the middle diagenesis, and experienced a series of diagenesis, in which the compaction, cementation and metasomatism reduce the sandstone reservoir. The primary porosity leads to the deterioration of the physical property, while the dissolution is beneficial to the formation of secondary pores, but the degree of corrosion is weak, and it is not enough to improve the physical properties of the reservoir. By analyzing the casting thin slices, ordinary thin slices and scanning electron microscopy, the pore types of the study area are primary intergranular residual pores, intergranular dissolution pores, rock dissolution pores, mold holes, micro casting holes, and micro pores. There are six kinds of fissure, among which the primary intergranular residual pores are less developed and intergranular pore is the main type. The main type of pore combination is intergranular dissolution pore. There are three types of laryngeal tract types: pore narrow throat, flaky or curved larynx and microlarynx, which mainly develop two types of curved larynx and microlarynx. On the basis of the analysis of the distribution of parameters and the characteristics of the capillary pressure curve, the pore structure of the study area is divided into four types: the type I is a low pore fine throat and a better effective reservoir; the second class is a low ultra low pore microlarynx, which is a general effective reservoir; class III is a ultra-low pore throat, and the industrial oil flow can be formed by transformation; type IV is ultra low and ultra-low pore. In the study area, the pore structure of the study area is complex, the middle value radius is small, the displacement pressure is relatively high, the efficiency of the mercury withdrawal is low, the maximum mercury saturation is high, the oil performance is relatively good, but the effective porosity is low in the total porosity of the rock, and the reservoir seepage ability is poor. Through the study, the study area spring four The overall porosity of the reservoir is dominated by low porosity and ultra-low porosity, and the permeability is dominated by ultra low permeability. The grain components of the reservoir, the sedimentary (micro phase) and the cementation are the main controlling factors of the reservoir physical property; the early full compaction and the medium cuttings are generally clay and silicon formed rock, which greatly reduces the primary pore; later carbon. The pore type cementation of the acid salt cements further obstructs the connectivity between pores and pores and reduces the physical property of the reservoirs. Although the dissolution is beneficial to the development of secondary pores, the strength is weak, and the significance of the reservoir is not significant, and the reservoir is generally densified. In accordance with the comprehensive properties of the reservoir, the lithology (particle size, composition, mud content), physical property (porosity, permeability) and pore junction are selected. Structure (pore throat median radius, displacement pressure), petrographic facies, oil-bearing (oil saturation), effective thickness and oil test daily production parameters as the characteristic parameters of reservoir comprehensive evaluation, comprehensive evaluation of reservoir reservoirs, and divided into one class, two types, three types, four types. The target layer of the research area is dominated by four types of reservoirs, three types of reservoir, accounting for 30.. The 14%, one class, two types of reservoirs are similar, respectively 17.68%, 17.97%., respectively, II, II, III sand formation of the best comprehensive type of reservoir, I sand group, the worst reservoir type, the most comprehensive type of reservoir in the third sand group, the proportion of 19.10%; the two type of reservoir comprehensive type in the third sand group is the most developed, accounting for 22 of the proportion. .47%; the three types of reservoir comprehensive types are the most developed in the I sand group, and the proportion is 31.78%. The four type of reservoir comprehensive type is the most developed in the IV sand group, and the proportion is the 43.24%. comprehensive sedimentary facies. The oil and gas accumulation law and the comprehensive evaluation result of the reservoir are screened in the favorable exploration area, and the reservoir is divided into one, two, and three types. One of the best, the two and the three is general.
【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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