摘要
利用乌南油田的低渗透油层取心岩样,模拟油层条件,试验研究了有、无天然裂缝岩样的应力敏感性,分析了应力增加过程中有、无天然裂缝岩样的渗透率保持率的差异性和应力恢复过程中有、无天然裂缝岩样的渗透率恢复率的差异性。结果表明:应力增加过程中,有效应力增加,有、无天然裂缝岩样的渗透率均迅速下降,有天然裂缝岩样的渗透率保持率小于无天然裂缝的岩样;应力恢复(应力增加到最大时,逐渐降低应力)过程中,有效应力降低,有、无天然裂缝岩样的渗透率均略有上升,有天然裂缝岩样的渗透率恢复率远小于无天然裂缝的岩样。为低渗透裂缝油藏开采过程中保护油气层提供了合理的重要依据。
Low permeability rock samples from Wunan Oilfield were used to simulate reservoir conditions. Experimental study was made on the stress sensitivity of rock samples with and without natural fractures,the difference of permeability maintaining rate of the rock samples with and without the natural fractures during stress increase and difference of permeability recovery ratio during permeability recovery were analyzed. The result shows that in the process of stress increase,when the effective stress increases,the rock permeabilities with and without the natural fractures decrease rapidly,their permeability maintaining rate is less than that of rock samples of natural fractures. Stress recovery (when the stress increases to its maximum value,and them it decreases gradually),the effective stress decreases,their permeability increases slightly,while the permeability of the rock with fracture is much lower than that of the one without fractures. It provides an important basis for formation protection in low permeability reservoir development.
出处
《石油天然气学报》
CAS
CSCD
北大核心
2010年第2期117-119,共3页
Journal of Oil and Gas Technology
基金
中国石油科技创新基金研究项目(2009D-5006-02-08)
关键词
应力敏感性
渗透率
低渗透油藏
裂缝
stress sensitivity
permeability
low permeability reservoir
fracture
