【摘要】：低滲透儲層是目前新區(qū)產(chǎn)能建設(shè)和油田上產(chǎn)的主體,而其中包含著大量砂礫巖儲層。長期的勘探開發(fā)實踐表明,低滲透砂礫巖儲層中微觀剩余油分布與孔隙結(jié)構(gòu)密切相關(guān),且孔隙結(jié)構(gòu)上的差別往往能在宏觀上決定油藏產(chǎn)能和開發(fā)效果,因此,在對孔隙結(jié)構(gòu)特征進行深入研究的基礎(chǔ)上,分析微觀剩余油分布規(guī)律,對經(jīng)濟有效地開發(fā)好低滲透砂礫巖油藏具有重要意義。論文以瑪北及其外圍地區(qū)百口泉組低滲透砂礫巖儲層為例。利用鑄體薄片觀察及掃描電鏡技術(shù),分析孔隙與喉道的類型、大小、分布特征以及相互組合關(guān)系,并根據(jù)常規(guī)壓汞資料分析各孔隙結(jié)構(gòu)參數(shù)及毛細管壓力曲線的特征。最終確定孔隙度、滲透率、排驅(qū)壓力、最大孔喉半徑、平均孔喉半徑和分選系數(shù)作為分類依據(jù),并結(jié)合孔隙類型以及毛細管壓力曲線特征,將低滲透砂礫巖儲層孔隙結(jié)構(gòu)劃分為Ⅰ型、Ⅱ型和Ⅲ型三類,其中Ⅰ型孔隙結(jié)構(gòu)少見,Ⅱ型和Ⅲ型孔隙結(jié)構(gòu)發(fā)育。選取具Ⅱ型和Ⅲ型孔隙結(jié)構(gòu)的巖樣,開展柱狀巖心驅(qū)替實驗,并與核磁共振測試及含油薄片熒光分析技術(shù)相結(jié)合,總結(jié)Ⅱ型和Ⅲ型孔隙結(jié)構(gòu)內(nèi)微觀剩余油的分布規(guī)律。實驗結(jié)果表明,Ⅱ型孔隙結(jié)構(gòu)的中-大孔隙內(nèi)基本無剩余油富集,絕大部分剩余油以孔內(nèi)半充填型和分散油滴型分布在小孔隙區(qū)間內(nèi),而微孔隙網(wǎng)絡(luò)多為“死油區(qū)”,發(fā)育孔喉充填型和孔內(nèi)半充填型剩余油,此外,Ⅱ型孔隙結(jié)構(gòu)中還存在少量裂縫滯留型剩余油以及相對較高比例的喉道滯留型和角隅型剩余油;Ⅲ型孔隙結(jié)構(gòu)內(nèi)剩余油也主要分布在小孔隙區(qū)間內(nèi),但中-大孔隙內(nèi)仍有孔喉充填型或孔內(nèi)半充填型剩余油富集,且相對于Ⅱ型孔隙結(jié)構(gòu),喉道滯留型、角隅型和分散油滴型剩余油含量較低。
[Abstract]:Low permeability reservoir is the main part of productivity construction and oil field production in the new area at present, and it contains a lot of sand and gravel reservoir. The long-term exploration and development practice shows that the micro-residual oil distribution in low-permeability sandy gravel reservoir is closely related to pore structure, and the difference in pore structure often determines reservoir productivity and development effect in macro level. On the basis of the deep study of pore structure characteristics, it is of great significance to analyze the distribution law of micro residual oil for the economic and effective development of low permeability sandy gravel reservoir. This paper takes the low permeability sandy gravel reservoir of Baikouquan formation in Mabei and its periphery as an example. The type, size, distribution and relationship of pore and throat were analyzed by means of casting thin slice observation and scanning electron microscope. The pore structure parameters and capillary pressure curve were analyzed according to conventional mercury injection data. Finally, porosity, permeability, displacement pressure, maximum pore throat radius, mean pore throat radius and sorting coefficient are determined as the classification basis, and combined with pore type and capillary pressure curve characteristics, The pore structure of low permeability sandy gravel reservoir is divided into three types: type 鈪，

本文編號：2237320