【摘要】：吳起油田曾岔區(qū)塊位于鄂爾多斯盆地伊陜斜坡中部,三疊系延長組作為該區(qū)主要含油層系,近年來長9油層組油氣勘探取得了重大突破,但石油地質(zhì)綜合研究程度尚低。論文以儲層地質(zhì)學、油氣成藏理論為指導,綜合巖石薄片、物性、壓汞等分析測試及試油試采資料,系統(tǒng)研究延長組長9油層組儲層特征及其油藏控制因素,可以為該區(qū)下步勘探部署提供依據(jù)。研究表明,長9油層組劃分為長91、長92和長93共3個小層,其中長91油層是主要的含油層位,各小層頂面構造總體表現(xiàn)為東高西低的單斜構造,局部發(fā)育由差異壓實作用造成的鼻狀隆起;長9油層組為三角洲前緣亞相沉積,水下分流河道為砂體主要成因類型;儲層巖石類型主要為灰色細粒長石砂巖;儲層建設性成巖作用有溶蝕作用和破裂作用,破壞性成巖作用有壓實、壓溶和膠結作用,總體處于中成巖A期;儲層儲集空間類型主要以粒間孔和長石溶孔為主,其余為少量巖屑溶孔、晶間溶孔、微孔和微裂縫孔,孔隙結構復雜;儲層孔隙度平均為8.90%,滲透率平均為0.46×10-3μm2,總體為低孔—超低滲儲層,儲層非均質(zhì)性強。長9油藏為典型的巖性油藏,油藏分布受烴源巖、過剩壓力、沉積微相、成巖作用改造的控制。研究區(qū)發(fā)育的優(yōu)質(zhì)烴源巖為長9油藏的形成提供了良好的物質(zhì)基礎;同時研究區(qū)處于過剩壓力低壓區(qū),是油氣運移的有利指向區(qū)域,水下分流河道砂體的展布形態(tài)和特征,原生粒間孔的保存和次生孔隙的發(fā)育是控制長9油氣聚集的最根本因素,分流河道主砂體及物性高值區(qū)是油氣聚集的主要區(qū)域。將沉積微相、砂體厚度、儲層物性,油層厚度和試油產(chǎn)量作為油氣有利區(qū)的劃分參數(shù)并預測了有利區(qū),其中Ⅰ類有利區(qū)有三個,Ⅱ類有利區(qū)有兩個,Ⅲ類有利區(qū)兩個,為下一步勘探開發(fā)提供有利依據(jù)。
[Abstract]:Zengcha block in Wuqi Oilfield is located in the middle of the Yishan slope in Ordos Basin. As the main oil-bearing system in this area, the Triassic Yanchang formation has made a great breakthrough in oil and gas exploration in Chang-9 formation in recent years, but the comprehensive study of petroleum geology is still low. Under the guidance of reservoir geology and the theory of oil and gas accumulation, the characteristics and reservoir control factors of Yanchang-9 reservoir formation are systematically studied by integrating the analysis, test and production data of rock sheet, physical property, mercury pressure and so on. It can provide the basis for the next exploration and deployment of the area. The results show that the Chang-9 formation is divided into three sub-layers: Chang-91, Chang-92 and Chang-93, in which Chang-91 reservoir is the main oil-bearing layer, and the top structure of each layer is characterized by a low monoclinal structure in the east, high in the west and low in the west. Local development of nasal bulge caused by differential compaction; Chang-9 reservoir formation is delta front subfacies sedimentary, underwater distributary channel is the main genetic type of sand body, reservoir rock type is mainly gray fine-grained feldspar sandstone, and subsurface distributary channel is the main genetic type of sand body. The constructive diagenesis of the reservoir is dissolution and fracture, and the destructive diagenesis is compaction, pressure solution and cementation, which is generally in the middle diagenetic stage A; The reservoir space types are mainly intergranular pore and feldspar solution pore, others are small amount of cuttings solution pore, intergranular solution pore, micro-pore and micro-fracture pore, the pore structure is complex; The average porosity and permeability are 8.90% and 0.46 脳 10 ~ (- 3) 渭 m ~ 2, respectively. The reservoir is a low porosity-ultra low permeability reservoir with strong heterogeneity. Chang-9 reservoir is a typical lithologic reservoir, and its distribution is controlled by source rocks, excess pressure, sedimentary microfacies and diagenesis transformation. The high-quality source rocks developed in the study area provide a good material basis for the formation of Chang-9 reservoir. At the same time, the study area is located in the area of excess pressure and low pressure, which is the favorable direction area for oil and gas migration. The distribution morphology and characteristics of underwater distributary channel sand body, the preservation of primary intergranular pores and the development of secondary pores are the most fundamental factors controlling the accumulation of Chang-9 oil and gas. The main sand body and the high value area of physical property in distributary channel are the main areas of oil and gas accumulation. The sedimentary microfacies, sand body thickness, reservoir physical properties, oil layer thickness and oil test production are used as the parameters for dividing favorable oil and gas zones and the favorable areas are predicted. There are three favorable areas for type 鈪，

本文編號：2440877