井研地区筇竹寺组页岩储层水平井钻井井壁稳定性评价  

Evaluation of Wellbore Stability during Horizontal Drilling in Qiongzhusi Formation Shale Reservoir in Jingyan Area

作　　者：智慧文[1] 栗涵洁 权子涵 Zhi Huiwen;Li Hanjie;Quan Zihan(Research Institute of Petroleum Engineering Technology,SINOPEC Southwest Oil&Gas Company,Deyang Sichuan 618000)

机构地区：[1]中国石化西南油气分公司石油工程技术研究院,四川德阳618000

出　　处：《中外能源》2024年第3期62-66,共5页Sino-Global Energy

基　　金：中国石化西南油气分公司科技项目“井研地区工程地质特征及钻井对策研究”(编号:KJ-541-1917)部分研究成果。

摘　　要：川西南井研区块筇竹寺组页岩气具有良好的开发前景,但由于对其岩矿组分、力学性质、水化特征等认识程度较低,钻井井壁稳定性认识不清,导致出现掉块、阻卡等复杂情况。为了充分认识该区寒武系筇竹寺组地层的井壁稳定性,明确粉砂质页岩水化作用及其对坍塌压力的影响规律,在岩石力学实验的基础上,研究不同钻井液浸泡时间对岩石力学参数的影响规律,建立考虑水化作用的井壁稳定性预测模型,分析不同井斜方位下坍塌压力的差异。研究结果表明:筇竹寺组伊蒙混层含量高,具有一定膨胀性,水化作用后导致岩石强度降低,对井壁稳定性有较大影响;不同钻井液体系对井壁稳定性的影响有差异,总体上油基钻井液更有利于井壁稳定;考虑了水化作用的井壁稳定预测模型更加符合实际,以此为依据,通过优化钻井液设计可以有效降低井壁失稳风险,提高钻井时效。The Qiongzhusi Formation shale gas in the Jingyan Block in southwestern Sichuan has good development prospects.However,due to the low level of understanding of its rock components,mechanical properties,hydration characteristics,etc.,and the stability of the wellbore,complex situations such as solids settling and sticking occur.To fully understand the wellbore stability of the Cambrian Qiongzhusi Formation in the area,clarify the hydration effect of silty shale and its impact on collapse pressure,the influence of different soaking time of drilling fluid on rock mechanics parameters is studied based on rock mechanics experiments.A wellbore stability prediction model considering hydration is built,and the differences in collapse pressure under different wellbore inclination orientations are analyzed.The research results indicate that the illite-mont-morillonite mixed layer in the Qiongzhusi Formation has a high content and certain expansibility.After hydra-tion,the rock strength drops,which has a significant impact on the stability of the wellbore.The impact of different drilling fluid systems on wellbore stability is various,and oil-based drilling fluids are more conducive to wellbore stability in general.The wellbore stability prediction model considering hydration is more practical.Based on this,optimizing the design of drilling fluid is beneficial for maintaining wellbore stability and improving drilling effectiveness.

关 键 词：井壁稳定性 粉砂质页岩 水化作用 井斜方位 坍塌压力 油基钻井液 

分 类 号：TE243[石油与天然气工程—油气井工程]