alluvialadj.冲积的；淤积的n.冲积土；淤积土alluvial community冲积带群落Alluvial fan facies冲积扇相alluvial brown soil棕色冲积土alluvial paddy soil冲积性水稻土alluvial plain area十积平原alluvial exploration砂金勘探alluvial sand bodies冲积砂体alluvial fan deposit冲积扇沉积,冲积扇层Alluvial Tin deposit砂锡矿床alluvial meadow soil冲积性草甸土