diluvial placer洪: I big; vast; grand积: amass; store up; accumulate砂矿床: placer洪积砂矿: proluvial placer残积砂矿床: eluvial placer deposit下载手机词典可随时随地查词查翻译关注微信公众号:chachacidian,回复:洪积砂矿床,即可在微信中查询翻译