短語(yǔ)詞組短語(yǔ)coal resource exploration 煤炭資源勘探coal seam exploration type 煤層勘探類(lèi)型coal geological exploration industry 煤田地勘單位coal field exploration 煤田勘探coal geological exploration units 煤炭地勘單位Coal Seismic Exploration 煤田地震勘探coal geological exploration unit 煤炭地質(zhì)單位coal -exploration direction 找礦方向 返回 coal exploration