Diluvium<span> was a term in </span>geology<span> for superficial deposits formed by </span>flood<span>-like operations of water, and so contrasted with </span>alluvium<span> or </span>alluvial<span> deposits formed by slow and steady </span>aqueous<span> agencies. The term was formerly given to the </span>boulder clay<span> deposits, supposed to have been caused by the </span>Noachian<span> deluge</span>
