After drilling the upper intervals with gas/air, water base muds were used to drill thelower parts of the holes, leading to a series downhole problems such as hole instability and mud losses.

• 分析了气体钻进后顶替钻井液初期容易发生井塌、井漏等复杂情况的原因,介绍了解决川东北地区气体钻进后井壁失稳的钻井液技术对策、技术方案及防止井壁失稳的钻井液工艺技术。