岩石可钻性各向异性评价模型研究

地层可钻性各向异性评价在直井防斜以及定向井井眼轨迹控制中具有重要的意义。为此，文章测试了大陆科探井岩心垂直于层面和平行于层面的岩石可钻性，以该实验数据及98组不同油气田、不同岩性的岩心垂直于层面和平行于层面可钻性实验数据为基础，用数理统计方法研究分析了垂直于层面和平行于层面岩石可钻性之间的相关关系，建立了用垂直于层面岩石可钻性预测平行于层面岩石可钻性的数学模型，给出了利用该模型评价地层可钻性各向异性的方法。

Model to Evaluate Anisotropy of Rock Drill-ability

Evaluation of formation drill-ability anisotropy has important effect for preventing deviation of straight holes and planning drilling trajectories of directional wells. Rock drill-ability is measured in the directions perpendicular and parallel to layering with the core samples that are cut from the continental scientific exploration well. Based on the test data and the 98 groups of data obtained by drill-ability tests in the directions perpendicular and parallel to layering from the cores with different lithology in several oil/gas fields, the correlation of drill-ability between the directions perpendicular and parallel to the bedding plane is investigated with mathematical statistics method. A mathematical model is developed to predict the rock drill-ability in the direction parallel to the bedding plane by the drill-ability in the direction perpendicular to the bedding plane. And the method is proposed to evaluate anisotropy of formation drill-ability by the model. (Financed by the Special Project of National Science Fund for the West, No. 90410006, and the Key Project of National Science Fund, No. 50234030)