摘要
通过实验对安塞油田致密砂岩储层压敏渗流特征进行研究。运用室内实验和理论分析相结合的方法，通过致密砂岩储层压力敏感性机理分析，将非达西渗流、岩石形变和有效应力的变化作为一个整体来研究压敏渗流特征。主要研究不同净围压下的孔渗关系及渗流曲线特征，实验研究表明在净围压小于某一值时，岩石形变特别是致密介质中裂隙的变化导致了渗流曲线特征的不同。当有效压力较低时，渗流曲线为非直线；但当有效压力超过某一值时，渗流曲线却为一条直线。这种渗流特征与岩石裂隙形变有关，存致密砂岩油气藏储集层近井区范围内，除孔隙尺寸原因以外，岩石形变是导致压敏渗流非达两特征的主要原因。该结论为致密砂岩油藏启动压力研究开辟了一条新途径。
Pressure-sensitive flow characteristics of tight sandstone reservoirs in Ansai Oilfield are studied through experiments. Combining laboratory experiments with theoretical analysis, changes of non-Darcy flow, rock deformation and effective stress are considered as a whole to study pressure-sensitive flow characteristics through analysis on pressure-sensitive mechanism of tight sandstone reservoirs. Relationship between porosity and permeability and flow curve characteristics under different net confining pressure are studied. Experimental studies indicate that rock deformation, especially fissure changes in tight media results in different flow characteristics when net confining pressure is less than a certain value. When effective pressure is lower, flow curve is a non-straight line. When effective pressure is higher than a certain value, flow curve becomes a straight line. These flow curve characteristics are related to rock deformation. Results indicate that in well areas near tight sandstone reservoirs, rock deformation is the main cause resulting in non-Darcy characteristics of pressure-sensitive flow except for the cause of pore size. This conclusion provides a new way for study on starting pressure in tight sandstone reservoirs.
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2009年第1期78-81,共4页
Petroleum Geology & Oilfield Development in Daqing
关键词
致密砂岩
储集层
压敏性
岩石形变
实验
tight sandstone
reservoirs
pressure-sensitivity
rock deformation
experiment
