油气地质与采收率2017，Vol.24Issue(6)：72-78,7.
超深致密砂岩储层裂缝壁面出砂机理及其对应力敏感性的影响
Mechanisms of sand production from fracture wall and its effect on stress sensitivity in ultra-deep tight sandstone reservoirs
摘要
Abstract
The stress sensitivity of permeability is always an important research topic in the area of tight oil and gas reser voir development.Six fractured samples were prepared from the downhole core samples in the ultra-deep tight sandstone gas reservoir,which were used to conduct the stress sensitivity evaluation experiment in the ultra-deep tight sandstone reservoir.Before and after the experiments of stress sensitivity,laser scan imaging was made on fracture wall.SEM was used to observe the micro-structure of the fracture wall.The research results show that the stress sensitive coefficients of the fractured samples of the ultra-deep tight sandstone reservoir range from 0.41 to 0.72,and the degree of stress sensitivity is from medium and weak to strong,which is significantly lower than that of the typical tight sandstone reservoir in China.The resuits of three-dimensional laser scanning imaging present that sand particles drop off from the fracture wall before and after stress sensitivity experiments.SEM image shows that the structure of most of the fracture wall is loose and weak before the experiment.During the stress sensitivity evaluation experiments of the fractured samples in the ultra-deep tight sandstone reservoir,the sand particles are separated from the walls of fractures under the effect of erosion,which is caused by drag force and particle erosion.Under the effect of drag force,the particles move and deposit in narrow place of the fractures.Due to a certain strength of particles,the deposited sand particles play a role on propped fractures with the increase of effec-tive stress,which can weaken the stress sensitivity to some extent.The degree of influence of sand production from fracture wall on decreasing stress sensitivity are different for fractures with different widths.The degree of weakening effect for fractures with medium width,relatively large width and relatively small width falls in turn.关键词
超深/裂缝/致密砂岩/应力敏感/出砂/拖曳力/颗粒剥蚀Key words
ultra-deep/fractures/tight sandstone/stress sensitivity/sand production/drag force/particle erosion分类
能源科技引用本文复制引用
张杜杰,康毅力,游利军,周振寰,朱金智,李家学..超深致密砂岩储层裂缝壁面出砂机理及其对应力敏感性的影响[J].油气地质与采收率,2017,24(6):72-78,7.基金项目
非常规油气层保护四川省青年科技创新研究团队项目“水力压裂页岩气井热处理解除损害及强化产能研究”(2016TD0016). （2016TD0016）
