钻井液与完井液2025，Vol.42Issue(5)：600-608,9.DOI:10.12358/j.issn.1001-5620.2025.05.005
准噶尔盆地南缘地区泥岩段多场耦合井壁失稳机理
Mechanism of Multi-field Coupled Wellbore Instability in the Mudstone Section of the Southern Margin of the Junggar Basin
高世峰 1屈沅治 1都伟超 2任晗 1庄严 3黄宏军1
作者信息
- 1. 中国石油集团工程技术研究院有限公司,北京 102206
- 2. 西安石油大学化学化工学院,西安 710065
- 3. 常州大学石油与天然气工程学院,江苏 常州 213164
- 折叠
摘要
Abstract
To understand the mechanisms of borehole wall instability of the easy-to-collapse formations in the southern margin of the Junggar Basin,mudstone cores were taken from the formation and studied through physio-chemical experiment,mechanical experiment and construction of a dynamic formation failure model.The results of the studies show that the mudstones in the southern margin of the basin contain 42%swelling clay minerals,the rate of swelling of the mudstone cores in contact with water is 30%or higher,and the percent recovery of the cores in hot rolling test is lower than 20%,indicating that the mudstone is quite easy to hydrate in water.The strength of the in-situ mudstones is lower than 40 MPa.After hydration,the strength and elastic modulus of the in-situ mudstones decrease exponentially,and the decreasing speed is fast at first,and then becomes slowly.As temperatures increase,the formation strength shows a trend of decrease,the speed of which is becoming faster.The cause of this phenomenon is"expand with heat and contract with cold".The air in the pores of the formation expands,causing a change in the internal stresses of the rock,thereby reducing its strength.A multifield coupling dynamic borehole wall stabilization model was constructed to more accurately calculate the collapse pressure equivalent densities under different well angles,azimuths and action times.The results of the calculation help reveal the multifield coupling borehole wall instability mechanism of the mudstone formations in the southern margin of the Junggar Basin,and provide a theoretical guidance for maintaining wellbore stability during drilling and for drilling design.关键词
准噶尔盆地南缘地区/多场耦合/泥岩/动态井壁失稳模型Key words
Southern margin of the Junggar Basin/Multifield coupling/Mudstone/Dynamic borehole wall instability model分类
能源科技引用本文复制引用
高世峰,屈沅治,都伟超,任晗,庄严,黄宏军..准噶尔盆地南缘地区泥岩段多场耦合井壁失稳机理[J].钻井液与完井液,2025,42(5):600-608,9.
