准噶尔盆地玛湖凹陷泥页岩水化特性及分类研究

准噶尔盆地玛湖凹陷在使用水基钻井液钻进时,因所用钻井液体系与地层配伍性差,导致地层崩落掉块严重,井壁失稳频发;且储层损害较大。为解决所存在的问题,对取自玛湖凹陷的岩样进行了全岩矿物成分与黏土矿物分析。在相关分析的基础上对该区块泥页岩的水化特性进行了预测;并通过水化膨胀与水化分散实验对所预测的泥页岩水化特性进行了验证。在室内实验的基础上,建立了泥页岩水化特性分类图版概念;并利用此图版对玛湖凹陷泥页岩的水化特性进行了准确和直观的分类界定,为今后开展的适用于该区块的多元协同钻井液体系中各个单元的权重设计,以及整个钻井液体系的技术研究提供了重要的理论指导依据,最终实现钻井液体系与地层的配伍,服务钻井作业。

The Characteristics and Classification of Hydration of Shale Fed from Mahu Sag in Dzungaria Basin

When the water based drilling fluid was used to drilling in Mahu Sag in northwestern margin of Dzungaria Basin, the compatibility between drilling fluid and formation was poor, thus phenomenon of caving and fall block of formation was serious, and degree of formation damage was heavy. To prove the problems, whole rock mineral analyses and clay mineral analyses of rock samples fed from Mahu Sag were analyzed in this paper, and the hydration characteristics of these rock samples was prediction which was based on correlation analysis, at the end, the prediction was proven by the results of swelling and distribution of shales. concept of classification chart was established based on the laboratory experiments, and by using this chart, hydration characteristics of shale fed from Mahu Sag could be accurate and visual classified, these achievements could be used as basis of theory guidance to design whole drilling fluids system which was suitable to Mahu Sag and the components of this system. At the end, the good compatibility between drilling fluid and formation could be realized, and serving to drilling operation.