玛湖凹陷致密砾岩油藏不同开发方式下原油微观可动性  

Microscopic Oil Mobility in Tight Conglomerate Reservoirs Under Different Development Modes,Mahu Sag

作　　者：万涛 张景[2] 董岩[2] WAN Tao;ZHANG Jing;DONG Yan(School of Petroleum,Karamay Campus,China University of Petroleum(Beijing),Karamay,Xinjiang 834000,China;Research Institute of Exploration and Development,Xinjiang Oilfield Company,PetroChina,Karamay,Xinjiang 834000,China)

机构地区：[1]中国石油大学(北京)克拉玛依校区石油学院,新疆克拉玛依834000 [2]中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000

出　　处：《新疆石油地质》2024年第3期327-333,共7页Xinjiang Petroleum Geology

基　　金：新疆维吾尔自治区自然科学杰出青年基金(2022D01E55);新疆维吾尔自治区“天山英才”青年拔尖人才项目基层科技骨干人才(2023TSYCJC0002)。

摘　　要：为评价玛湖凹陷三叠系百口泉组致密砂砾岩油藏原油可动性,通过渗吸、离心以及吞吐试验,对比了Ⅰ类和Ⅱ类储集层的典型岩心样品可动油分布特征。玛湖凹陷低渗透砾岩储集层渗吸出油量与孔隙结构有关,小孔隙体积占比越高,渗吸效果越好,经过144 h渗吸驱油,采收率可达30.9%,但是驱油进程缓慢,对大孔隙原油动用程度不高。在地层温度和40 MPa压力下,在3轮次CO_(2)吞吐过程中,每轮次的采出程度均增加,第1轮次采出程度增幅相对较高,换油率达27%,随着吞吐轮次的增加,采出程度增幅逐渐降低,而N_(2)吞吐开发第1轮次换油率为15%,因此,CO_(2)吞吐开发效果较好。In order to evaluate the oil mobility in the tight sandy conglomerate reservoirs of the Triassic Baikouquan formation in the Mahu sag,the distribution characteristics of movable oil in typical rock samples from TypeⅠand TypeⅡreservoirs were compared through im⁃bibition,centrifugation,and huff⁃n⁃puff tests.For the low⁃permeability conglomerate reservoirs in the Mahu sag,the imbibition oil recovery is related to the pore structure of the rock.The higher the proportion of small pores,the better the imbibition effect.After 144 hours of oil displacement by imbibition,the recovery rate can reach 30.9%,but the oil displacement process is slow,with low utilization of large pores.Under reservoir pressure of 40 MPa and reservoir temperature,during three cycles of CO_(2)huff⁃n⁃puff process,the recovery percent of each round increase,with the highest increase observed in the first cycle,reaching an oil exchange ratio of 27%.As the huff⁃n⁃puff cycle increas⁃es,the increment in recovery percent gradually decreases,and the oil exchange ratio of N_(2) huff⁃n⁃puff in the first cycle is 15%.Therefore,CO_(2)huff⁃n⁃puff has the best development effect.

关 键 词：玛湖凹陷 百口泉组 致密砾岩油藏 可动油饱和度 核磁共振 驱油效率 

分 类 号：TE122.1[石油与天然气工程—油气勘探]