西南石油大学学报（自然科学版）Issue(5)：97-104,8.DOI:10.11885/j.issn.1674-5086.2013.06.30.03
页岩层理对水平井井壁稳定的影响
Influence of Shale Bedding Plane on Wellbore Stability for Horizontal Wells
摘要
Abstract
Brittle shale formation developed a lot of bedding plane and microfissuring in marine shale gas region of South China. Borehole collapse problem of horizontal well in bedding plane formation has seriously hampers the development process. Therefore based on the linear elastic mechanics model of borehole stability and the single weak-plane strength theory,the borehole stability model for horizontal wells in bedding plane formationis is established. It considers influence of the attitude of bedding plane,strength of weak bedding plane,rock strength,horizontal azimuth,weakening of bedding plane (water cuts)and etc. Based on these,this paper quantitatively analyzed the effects of attitude of bedding plane and water cuts. The results show that collapse pressure is controlled by attitude of bedding plane and horizontal azimuth,and that the borehole stability of horizontal well is better when dip angle of bedding is 0°<θDIP<15° and 75°<θDIP<90°. Bedding weakening is one of the important factors,which lead to borehole collapse.No matter how attitude of bedding plane change,with water cuts of bedding increase,borehole collapse pressure increases rapidly,and the increase range of collapse pressure is about 12∼18 MPa. When the water cuts is 20%,collapse pressure increases by 37.9%.关键词
页岩气/层理/水平井/井壁稳定/弱面/坍塌压力Key words
shale gas/bedding plane/horizontal well/wellbore stability/weak plane/collapse pressure分类
能源科技引用本文复制引用
马天寿,陈平..页岩层理对水平井井壁稳定的影响[J].西南石油大学学报（自然科学版）,2014,(5):97-104,8.基金项目
国家重点基础研究发展计划（2013CB228003）。 （）
