摘要
首次利用大尺寸真三轴岩石力学实验系统,对缺陷储层重复压裂后裂缝的分布进行了研究。实验结果表明:应力重定向对新裂缝的分布情况影响较大;对缺陷储层进行水力压裂,当外加载荷达到某一临界值时,储层中的缺陷被激活,并产生比较复杂的裂缝;重复压裂时,新裂缝是否沿预置裂缝扩展在很大程度上受地应力状态、地质条件等因素控制;尤其是在较高的均匀压应力状态下,缺陷储层中新裂缝的产生方位可能与预置裂缝无关。
The distributions of fractures after re-fracturing in defective reservoirs are studied by using a series of large size true tri-axial test systems for the first time. The experimental results show that the stress redirection has a great impact on the distribution of new cracks. When the load reaches a certain critical value, defects will be activated during hydraulic fracturing, and more complex fractures will be formed. Whether new fractures propagate along the preset fracture or not largely depends on the stress state, geological conditions, and so on. Especially under the higher uniform stress, the direction of new fractures has nothing to do with the preset ones.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2013年第3期567-570,共4页
Chinese Journal of Geotechnical Engineering
基金
国家科技重大专项课题项目(2008ZX05031-002-003-001)
关键词
重复压裂
缺陷
预置裂缝
围压
地应力
re-fracturing
defect
preset fracture
confining pressure
in-situ stress
