alluvion
名词 alluvion:
gradual formation of new land, by recession of the sea or deposit of sediment
the rising of a body of water and its overflowing onto normally dry land
同义词:flood, inundation, deluge
clay or silt or gravel carried by rushing streams and deposited where the stream slows down
同义词:alluvial sediment, alluvial deposit, alluvium