alluvial deposit英 [əˈluːviəl dɪˈpɒzɪt]美 [əˈluːviəl dɪˈpɑːzɪt]冲积矿床机械英英释义nounclay or silt or gravel carried by rushing streams and deposited where the stream slows downSynonym:alluvial sedimentalluviumalluvion双语例句