摘要
储层岩石的微观孔隙结构特征直接影响其储集和渗流能力,并最终决定油气藏产能的大小。使用恒速压汞测试技术,对低渗致密火山岩气藏微观孔喉发育特征研究表明,低渗火山岩气藏喉道半径非常细微但孔道半径较大,不同渗透率大小的储层喉道发育特征差异明显,主流喉道半径与储层渗透率具有较好的函数关系,喉道控制储层渗流能力。与渗透率接近的砂岩储层相比,低渗火山岩储层孔道半径较大但分布范围相对较小、孔喉比超大且呈多峰态分布,孔喉匹配关系复杂,开发过程中极易产生水锁伤害。同时数学拟合结果表明,火山岩气藏孔喉半径比加权均值随渗透率的增大而减小,但其相关性小于低渗砂岩孔喉比均值与渗透率之间的相关性;储层有效孔道、喉道体积与孔隙度和渗透率具有较好的相关性,但其与前者的相关性好于后者,这与低渗砂岩储层规律相反。
The storage and flow capacity as well as the ultimate recovery of reservoir are directly affected by its micro-pore structure which determines the productivity of reservoir.The characteristics of the micro pore-throat in low permeability volcanic gas reservoir were analyzed using the constant-rate mercury injection technology.The result shows that the radius of the pore throat is very small and the pore path is large.There are obvious differences among the radius of pore throat in different permeability reservoir.There is a very good functional correlation between the mainstream pore throat and the permeability.The pore path controls on the flow capacity of reservoir.The volcanic gas reservoir is characterized by larger pore body and the pore-throat ratio than that of sandstone reservoir.There are several peaks in the distribution figures of the pore-to-throat ratio of volcanic reservoir,but one of sandstone reservoir,which is easy to cause the water locking damage.Mathematics matching shows that the average value of pore-to-throat decreases when the permeability of volcanic increases,but the relationship between the parameters of micro-structure and physical property of volcanic reservoir is more complicated than that of sandstone reservoir.It has also found that the effective pore throat and pore path volume are correlative with the porosity and permeability of volcanic reservoir.But the former is better than the later,which is opposite to the sandstone reservoir
出处
《断块油气田》
CAS
北大核心
2010年第5期548-552,共5页
Fault-Block Oil & Gas Field
关键词
低渗透
微观结构
孔喉特征
恒速压汞
火山岩气藏
孔喉比
low permeability
micro-pore structure
pore-throat characteristics
constant-rate mercury injection technology
volcanic gas reservoir
pore-to-throat ratio.
