1·This paper analyzes the drillability, hole-making and carry of coarse grain concerning the Nubia sandstone, and concludes that it is suitable to be the crossing strata.
在可钻性、成孔性及粗颗粒可携带性等方面对努比亚砂岩进行了分析，认为将其作为穿越地层是可行的。
2·Based on the features of geomorphology and strata in the crossing area, the Nubia sandstone is selected to be the surrounding rock.
根据穿越处地貌及地层特性决定将努比亚砂岩作为定向钻穿越的围岩。