國(guó)景星+宋曉倩+王思文+郭云龍+彭雪還

摘要：惠民凹陷商河油田商一區(qū)油氣儲(chǔ)層經(jīng)過(guò)近40年的勘探開(kāi)發(fā)，挖潛難度越來(lái)越大。為了進(jìn)一步搞清該區(qū)剩余油分布規(guī)律，充分利用研究區(qū)豐富的巖芯、測(cè)井等資料，對(duì)沙二下亞段三、四砂組河口壩儲(chǔ)層的垂向級(jí)次劃分、單一河口壩識(shí)別及發(fā)育特征、垂向演化規(guī)律等開(kāi)展精細(xì)研究。結(jié)果表明：河口壩儲(chǔ)層發(fā)育5級(jí)構(gòu)型界面，其中五、四級(jí)界面的成因類型分別為洪泛泥巖、砂體披覆泥巖，三級(jí)界面的成因主要為物性差異沉積、成巖鈣質(zhì)砂巖，并進(jìn)一步細(xì)分為泥質(zhì)夾層、物性?shī)A層和鈣質(zhì)夾層3類；三級(jí)界面中泥質(zhì)夾層的橫向連續(xù)性好于物性?shī)A層和鈣質(zhì)夾層，延伸距離為300～800 m，沿河口壩進(jìn)積方向，在坡折帶處夾層傾角最大可達(dá)8°，至湖盆內(nèi)部夾層傾角一般小于2°，沿垂直于砂體推進(jìn)方向，夾層傾角一般低于1.5°；儲(chǔ)層頂面高程差異、壩間沉積、壩緣側(cè)向交錯(cuò)疊置、曲線形態(tài)及砂體沉積厚度差異是單一河口壩側(cè)向邊界的4種識(shí)別標(biāo)志；基準(zhǔn)面的升降變化控制了沉積砂體間疊置關(guān)系，決定了河口壩砂體的沉積厚度及儲(chǔ)層物性特征。該研究成果對(duì)于指導(dǎo)商河油田及相似油田開(kāi)展后期剩余油分布預(yù)測(cè)具有借鑒意義。

關(guān)鍵詞：河口壩；儲(chǔ)層；構(gòu)型；界面級(jí)次；垂向演化；沙二段；商河油田；惠民凹陷

中圖分類號(hào)：P618.13；TE122.2 文獻(xiàn)標(biāo)志碼：A

Abstract： After nearly 40 years exploration， the development of petroleum reservoir in Shangyi block of Shanghe oilfield， Huimin sag becomes much more difficult. In order to find the distribution of remaining oil， based on the abundant core and well logging data， the mouth bar reservoir in the third and the fourth sand groups of the second member of Shahejie Formation was analyzed for many aspects， including the grading system of architecture interfaces， the identification and characteristics of a single mouth bar and the vertical evolution law. The results show that the mouth bar reservoir can be classified into 5 grades architecture interfaces； the origin types of the fifth and fourth architecture interfaces are flood shale and argillaceous layers， respectively； the origin types of the third architecture interface are sedimentary with poor physical properties and diagenetic calcareous sandstone， and can be further subdivided into shale interlayer， calcareous interlayer and transitional interlayer； the shale interlayer has more lateral continuity than the calcareous and transitional interlayers in the third architecture interface， and can extend for 300-800 m； along the progradation direction of mouth bar， the dip angle of interface in the slope break belt can up to 8°， while the dip angle is less than 2° in the flat terrain； along the vertical provenance direction of sandbody， the dip angle of interface is generally below 1.5°； four identification marks recognizing lateral boundary of single mouth bar include that the top surface altitude difference of reservoir， the appearance of interval zone of mouth bar deposits， the fringe of two mouth bars overlapping each other and the existing difference from curves and deposition thickness of sandbody； the fluctuation of base level controls the superimposed relationship of sandbody， and determines the deposition thickness of mouth bar sandbody and the physical characteristics of reservoir. This results have an important significance in guiding prediction of the remaining oils distribution in Shanghe oilfield and other similar oilfields.