摘要
中国石油先后在准噶尔盆地彩南地区、鄂尔多斯盆地东缘大宁-吉县和延川南区块实现高产煤岩气突破,展示了深层煤层气巨大的开发潜能。四川盆地龙潭组“超压、超饱和”煤岩气勘探潜力大,有望成为非常规油气勘探开发新领域。NT1H井是四川盆地第一口深层煤岩气水平井,钻井过程中面临井漏风险高、煤岩易失稳垮塌、薄储层井眼轨迹控制难度大等技术难题。通过地质工程一体化协同研究,共同确定能够兼顾地质发现需求与工程风险控制的“双甜靶点”;采用“四开+备用膨胀管”井身结构拓展技术、近钻头地质探边、高效长寿命钻头与工具优选,油基钻井液等技术,顺利完成该井施工。取得的现场经验与认识可以为四川盆地煤岩勘探开发提供技术支持和优化指导,后续井可以探索开展井身结构优化和水基钻井液先导试验,进一步降低煤岩气勘探开发成本。
PetroChina has achieved high-yield coal-rock gas breakthroughs in the Cainan area of the Junggar Basin,as well as the Daning-Jixian and Yanchuan South blocks along the eastern margin of the Ordos Basin,demonstrating the immense development potential of deep coal-rock gas.The Longtan Formation in the Sichuan Basin exhibits significant exploration prospects for"overpressured and supersaturated"coal-rock gas,positioning it as a promising frontier for unconventional oil and gas exploration and development.Well NT1H,the first deep coal-gas horizontal well in the Sichuan Basin,encountered challenges such as high risk of fluid loss,instability and collapse of coal-bearing strata,and difficulties in trajectory control within thin reservoirs.Through integrated geological-engineering collaboration,dual"sweet spots"were identified to balance geological discovery objectives with engineering risk mitigation.Key technologies included:A four-section well structure with a contingent expandable liner to enhance wellbore stability;Near-bit geosteering for precise reservoir boundary detection;Optimization of high-efficiency long-life drill bits and tools;Application of oil-based drilling fluids for enhanced performance.The successful implementation of Well NT1H provides critical technical insights can provide technical support and optimization guidance for the exploration and development of coal-rock gas in the Sichuan Basin,as well as for the subsequent well exploration to carry out wellbore structure optimization and pilot tests of water-based drilling fluids,thus further reducing exploration and development costs.
作者
范宇
FAN Yu(PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China)
出处
《钻采工艺》
北大核心
2025年第3期56-61,共6页
Drilling & Production Technology
基金
中国石油集团公司项目“风险勘探领域和目标研究、工程技术攻关及现场试验”(编号:2023YQX10104)。
关键词
非常规油气
深层煤岩气
龙潭组
探边工具
一趟钻
unconventional oil and gas
deep coal-rock gas
Longtan formation
boundary detection tools
one-trip drilling
