摘要
储层物性下限研究是客观合理认识气藏的基础,常规的研究方法在亲水低孔低渗透储层物性下限的研究中具有较大的局限性。为准确界定该类储层的物性下限,以气体低速渗流机理为指导,以气体低速渗流实验为基础,研究了气体在亲水低孔低渗透储层中的渗流规律,并建立了应用启动压力梯度确定该类储层物性下限的方法,即利用气体低速渗流实验查清研究区储层气体的渗流规律,建立孔隙度、渗透率与启动压力梯度的关系,界定启动压力梯度的临界点,进而确定储层的物性下限。应用该方法对蜀南河包场地区须家河组气藏亲水低孔低渗透储层物性下限进行研究,确定了河包场地区渗透率下限为0.05×10-3μm2,须二段、须四段、须六段有效储层孔隙度下限分别为8.61%,4.67%,5.21%。
Study on the lower limit of reservoir plays an important role in reservoir exploration and development. Conventional methods are greatly limited in determining the lower limit of hydrophilic,low porosity and low permeability reservoir. In this paper, guided by the low-speed seepage mechanism,and based on the low-speed gas seepage experiment,the seepage mechanism of gas within the low permeable and flooded reservoir is studied and the methods determining cut-off parameters within the hydrophilic low permeable reservoir are proposed by means of start-up pressure gradient. That is,the fluid mechanism within the reservoir is ascertained by the seepage experiment of low speed gas so as to construct the relationship between porosity, permeability and startup pressure gradient,as well as the threshold value of startup pressure gradient,and then the petrophysical cut-off of reservoir may be determined subsequently. Using the methods above-mentioned, the lower limit of porosity and permeability of the T3X gas reservoir was studied. The result shows that:the lower limit of porosity in T3X2 ,T3X4 and T3X6 formation are 8.61% ,4.67% and 5.21% respectively ; the lower limit of permeability is 0.05×10-3μm2.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2010年第5期57-60,共4页
Petroleum Geology and Recovery Efficiency
基金
国家重大专项"大型油气田及煤层气开发"子课题(2008ZX5001)
关键词
低速渗流
启动压力梯度
低渗透储层
物性下限
须家河组
low-speed seepage
starting pressure gradient
reservoir petrophysical cut-off
Hebaochang area
Xujiahe formation
