短語(yǔ)詞組短語(yǔ)placer r deposit 砂積礦床placer gold deposit 砂金礦床the placer gold deposit 砂金礦體aeolian placer deposit 風(fēng)成砂礦床offshore placer deposit 近海砂礦quarternary placer deposit 第四紀(jì)砂礦床eluvial placer deposit 殘積砂礦床alluvial placer deposit 沖積砂礦床 返回 placer deposit