摘要
砂岩油藏在长期注水开发过程中,油藏储层孔隙结构发生了较大变化,由于储层渗透率增大,孔喉半径增大,易在储层中形成高渗带及特高渗透带,即大孔道。在大孔道发育的地层中,大孔道成为注入水渗流的优势通道,注入介质的波及范围很难提高。注入水沿大孔道中的低效或无效循环使储层中的其它部位很难受效,严重影响驱油效率,致使平面上剩余油饱和度差异明显。因此,砂岩油藏大孔道对储层渗透率及注采工艺有着重要的影响。本文在调研了大量国内外资料的基础上,对油层大孔道研究背景、研究现状作了回顾,对大孔道的形成机理、识别技术与描述技术等研究作了综述,提出了今后油层大孔道研究的重点、难点,以及对中高含水期注水开发油田的重要意义。
After long time development by waterflooding,the pore structure of sandstone reservoir changes a lot.Because of the increasing of permeability and pore-throat radius,high permeability zone and extremely high permeability zone may form in reservoirs,i.e.large pore path.The large pore path would be the preferred path of injected water,and it is hard to improve the sweep area.Injected water circulates around large pore path at low efficiency or inefficiently to make it difficult to sweep other parts of a reservoir,thus severely affecting oil displacement efficiency and resulting in obvious difference in areal residual oil saturation.Therefore,large pore path in sandstone reservoir will have significant effect on reservoir permeability and injection-production process.This paper investigates a large amount of domestic and foreign data,reviews the study background and current status of large pore path,summarizes the forming mechanism,identification and description techniques of large pore path,and puts forward the focal point and difficulty in the study.This study is of significance to waterflooding oilfield in medium-high water cut stage.
出处
《特种油气藏》
CAS
CSCD
2006年第6期10-14,共5页
Special Oil & Gas Reservoirs
基金
中国石油天然气集团公司石油科技中青年创新基金项目(编号:04E7047)
教育部博士点基金项目(编号:20040615004)联合资助
关键词
砂岩油藏
大孔道
形成机理
识别技术
渗透率
孔喉半径
研究综述
sandstone reservoir
large pore
forming mechanism
identification technique
permeability
pore-throat radius
study overview
