placer mining
短語(yǔ)詞組
- gold placer -mining 采金場(chǎng)
- placer gold mining 砂金礦開(kāi)采
- placer r mining 砂礦淘采
- beach placer mining industry 海濱砂礦開(kāi)采業(yè)
- beach placer mining 海濱砂礦開(kāi)采
- method of littoral placer mining 濱海砂礦開(kāi)采法
- hydraulic mining of placer 砂礦露天水力開(kāi)采 返回 placer mining