low coal seam meaning in Chinese

薄煤层

Hydrogeological condition for coal mining of lower coal seam group in nantun coal mine
南屯煤矿下组煤开采水文地质条件
Analysis on water isolation layer conditions of taiayuan group lower coal seam mining of hebi coal mine
鹤壁矿区开采太原群下组煤的隔水层条件分析
Assesment of hydrogeological conditions and prediction of water gush for mining the lowest coal seam in xingtai coal mine
台煤矿下组煤开采水文地质条件评价及突水危险性预测
Analysis on the principle of making complete sets of equipment on the working faces of the coal planer and its practicability in the low coal seams
刨煤机工作面设备配套原则及在薄煤层的实用性浅析