COAL STRUCTURE
镜质体
煤结构
煤组成结构
煤体结构
煤田构造
结构
煤焦结构
煤层构造形态
Large surface coal mine
weak structure coal and rock
Complex Near-surface Structure
complicated surface structure
EBG high-impedance surface structure
fine investigation of near surface structure
functional surface structure
investigation of near-surface structure
investigation on near surface structure
modularization of the mould’s surface structure
moving down the structure surface