本文選題：沉積微相　切入點：巖石學特征　出處：《長江大學》2015年碩士論文　論文類型：學位論文

【摘要】：麻黃山西區(qū)塊地處鄂爾多斯盆地天環(huán)向斜中段的西部地區(qū),研究區(qū)的西部為西緣沖斷帶中段一馬家灘段與天環(huán)向斜中段連接過渡的部位。其構(gòu)造作用在受斷裂作用影響下的二級斷塊背斜帶對油氣運移聚集起主要控制作用,局部以背斜、斷塊及鼻狀構(gòu)造為主要的地質(zhì)構(gòu)造。研究區(qū)目的層段為長6、長8油組,平面控制面積120.8km2,累計埋深2400-2900米,完鉆探井44口,均有良好油氣顯示。延長組長6、長8油組以巖性油藏為主,儲層砂體主要為三角洲類型,具有埋藏深、隱蔽性強的特點；麻黃山西區(qū)塊長6、長8油組儲層為典型的低孔-特低孔、超低滲-特低滲儲層。在以石油地質(zhì)理論為指導,本文根據(jù)宏微觀相結(jié)合的研究思路,研究了麻黃山西區(qū)塊長6、長8油組儲層的巖石學特征、沉積微相、成巖作用、物性及非均質(zhì)性特征,并對研究區(qū)的儲層進行分類與儲層評價標準,確定和指出了有利的優(yōu)選目標區(qū),為油田更好的指導下一步的油氣勘探工作。在巖心觀察和測井資料綜合解釋的基礎(chǔ)上,采用的原理是旋回一厚度對比及高分辨率層序地層劃分與對比,運用不同成因砂體對比模式及空間接觸關(guān)系處理方式,對全區(qū)44口井長6、長8油組沉積期的小層劃分與對比,將長6劃分為3個砂組9個小層,長8劃分為2砂組6個小層；建立了地層單元等時地層格架。利用碎屑顆粒組分石英、長石、巖屑含量、地震均方根振幅屬性圖、砂組砂巖厚度等平面圖展布特征及砂組砂體百分含量圖等多因素綜合分析,對研究區(qū)物源進行了多元綜合分析,發(fā)現(xiàn)長6、長8油組的沉積物源主要是來自研究區(qū)西北方向。結(jié)合區(qū)域沉積背景資料,通過對測井、粒度的分析,對比巖心的觀察、描述及對取心井資料的認識,對研究區(qū)沉積微相類型及沉積演化規(guī)律進行了研究,可以認為研究區(qū)長6、長8油組沉積期為三角洲前緣環(huán)境。主要發(fā)育的微相有水下分流河道、席狀砂、遠砂壩、河口壩、間灣。長6油組砂巖成份主要有巖屑質(zhì)長石砂巖、長石質(zhì)石英砂巖,有少量長石巖屑砂巖；長8油組砂巖成份主要有巖屑砂巖、巖屑質(zhì)石英砂巖,有少量長石砂巖、長石質(zhì)巖屑砂巖。成分成熟度偏低,分選中等-好,磨圓度以次棱-次圓狀為主；交接類型占主導的是孔隙式膠結(jié),其次為孔隙-基底式膠結(jié)。長6油組填隙物主要為碳酸鹽類,長8油組填隙物主要為碳酸鹽類和粘土礦物。本區(qū)的主要孔隙類型有原生粒間孔、粒間溶孔、長石溶孔、巖屑溶孔、微裂縫等5種孔隙類型,其中以粒間孔隙為主。喉道類型可劃分為微喉道、片狀、彎片狀喉道三種,主要為彎片狀、微喉道,儲層滲透性很差。綜合發(fā)現(xiàn),兩個油組儲層均表現(xiàn)為低孔-特低孔、超低滲-特低滲儲層。研究區(qū)長6、長8油組儲層總體處于中成巖A階段。通過一系列的成巖相研究可看出,本研究區(qū)發(fā)育斑狀粒間溶孔成巖相、碳酸鹽膠結(jié)成巖相、泥質(zhì)膠結(jié)成巖相、致密壓實成巖相。通過收集的試油資料,對比對應儲層成巖相相關(guān)性進行分析,發(fā)現(xiàn)斑狀粒間溶孔成巖相與油氣有著很好的對應關(guān)系,可以看出建設(shè)性成巖作用對儲層的物性變好有較好的改造作用,因而可以知道該類儲層含油氣較好。沉積作用和成巖作用是研究區(qū)儲層物性的主控因素。儲層致密化的主要原因是由于碎屑顆粒中長石、巖屑等不穩(wěn)定組分及雜基含量較高,通過壓實作用及膠結(jié)作用使原生孔隙大大降低,由于成巖期溶蝕作用不強,次生孔隙不發(fā)育,導致儲層致密化。針對儲層的特征和性質(zhì),選用孔隙度、砂巖厚度、滲透率及泥質(zhì)含量等4個參數(shù)建立評價標準,運用灰色系統(tǒng)理論及聚類分析方法,對儲層進行評價,將研究區(qū)的儲層類型劃分為Ⅰ類、Ⅱ類、Ⅲ類、Ⅳ類。根據(jù)在平面上的展布儲層類型的特征并結(jié)合沉積相圖,發(fā)現(xiàn)Ⅰ類、Ⅱ類儲層主要集中在水下分流河道微相中,其次在河口壩、遠砂壩微相中。遠砂壩中主要發(fā)育Ⅱ類、Ⅲ類儲層。河口壩中主要發(fā)育Ⅱ類儲層,有少部分Ⅲ類儲層。在席狀砂、遠砂壩中以Ⅲ類、Ⅳ類儲層交互為主。在上述分析的基礎(chǔ)上,通過有效砂厚、儲量豐度、儲層類型相及構(gòu)造部位等圖疊合,結(jié)合油氣分布規(guī)律研究、儲層分類的評價標準,對研究區(qū)目的層段的有利區(qū)進行了預測,優(yōu)選出5個有利成藏區(qū)塊。
[Abstract]:The Shanxi block is located in Ordos basin ephedra Tianhuan syncline middle western region, the western region of the thrust belt in the western margin of a middle Majiatan section and Tianhuan Syncline area. The middle connecting structure in by fracture under the effect of two faulted anticline belt on the migration and accumulation of oil and gas has main control in effect, local anticline, faulted nose structure and geological structure. The main target layer in the study area is 6, 8 oil group, plane control area of 120.8km2, total depth of 2400-2900 meters, drilled 44 exploratory wells, have good oil and gas shows. Yanchang Formation Chang 6, Chang 8 oil group the lithologic oil reservoir, reservoir sand bodies are mainly delta type, with burial depth, concealed features; ephedra block of Shanxi Chang 6, Chang 8 oil reservoir is typical of low porosity, low permeability and extra low permeability reservoir. In petroleum geology theory this paper, based on the macro Study on the idea of microcosmic study, ephedra Shanxi block long 6, long 8 reservoir petrology, sedimentary facies, diagenesis, physical property and heterogeneity, and the reservoir of the study area classification and reservoir evaluation standard, determine and points out the favorable target selection for the oil area, to better guide the next exploration work. Based on the core observation and logging comprehensive interpretation, the principle is a cycle thickness correlation and high resolution sequence stratigraphic division and correlation, the contact relation between different sand contrast mode and space approach, 44 of the region's export well Chang 6, Chang 8 oil formation during the deposition of thin layer division and contrast, 6 will be divided into 3 sand groups 9 small layer 8 is divided into 2 sand groups 6 layers; established stratigraphic isochronous stratigraphic framework. The detrital quartz, feldspar group, debris content the earthquake. The root mean square amplitude attribute graph, multi factor comprehensive analysis of sand group sandstone thickness plane graph distribution characteristics and sand formation sand body content on the map, the research area source of multivariate analysis, found 6, sediment source of Chang 8 oil group is mainly from the northwest study area. Combined with the regional sedimentary background based on the data, logging, granularity analysis, comparative observation of core, description and understanding of coring data, sedimentary microfacies and sedimentary evolution in the study area were studied. The study area can be 6, the delta front environment of Chang 8 oil formation. The main microfacies are developed the underwater distributary channel, sand sheet, far sand dam, mouth bar, interdistributary bay. Chang 6 oil sandstone composition are mainly lithic feldspar sandstone, feldspathic quartz sandstone, with a small amount of feldspar lithic sandstone; sandstones of Chang 8 oil ingredients are mainly lithic sandstone, lithic quartz sand 宀，

本文編號：1598464