东北石油大学学报2025，Vol.49Issue(2)：84-96,13.DOI:10.3969/j.issn.2095-4107.2025.02.007
塔西南高地应力地层井壁失稳特征及影响因素分析
Wellbore instability characteristics and influencing factors of high in-situ stress formations in Southwest Ta-rim Basin
摘要
Abstract
The high in-situ stress formations in the Southwest Tarim Basin are characterized by well-de-veloped fractures and strong fragmentation,making conventional wellbore stability models unable to ac-curately reflect wellbore instability patterns.This study identifies high-stress formations using the strength-to-stress ratio and analyzes the engineering manifestations of wellbore instability,clay mineral characteristics,block shedding features,and rock mechanical properties in these formations.Consider-ing the discontinuous features of high-stress formations,a discrete element wellbore stability model based on force equilibrium was established to investigate the effects of varying stress states,stress rati-os,and drilling fluid filtration coefficients on wellbore stability.The results indicate that when the strength-to-stress ratio of the formation is below 2.5,wellbore instability risks increase significantly,manifested as fluid loss and stuck pipe incidents.High stress levels or larger stress ratios further reduce the safe density range of drilling fluids,thereby increasing wellbore instability risks.Additionally,for every 0.25 increase in the filtration coefficient,the risk of wellbore instability increases by 1.2 times.These findings provide important references for the design of drilling fluid parameters and the control of wellbore stability in high-stress formations.关键词
高地应力地层/井壁稳定性/坍塌压力/钻井液密度/塔西南Key words
high in-situ stress formation/wellbore instability/collapse pressure/drilling fluid density/Southwest Tarim Basin分类
石油、天然气工程引用本文复制引用
李佳欣,陈勉,夏阳,卢运虎,周波,张樱曦,项建..塔西南高地应力地层井壁失稳特征及影响因素分析[J].东北石油大学学报,2025,49(2):84-96,13.基金项目
国家自然科学基金重点项目(52334001) （52334001）
