sheetwash
noun1
A thin layer of unchanneled water that flows over land, for example during a storm when the ground is too saturated to absorb any more water; if it lasts long enough, such flow forms rills and then larger channels.
- […] there is no indication that the side "stream" that covered Blue Babe with silt continued in its bed over a long period becayse the hill shows neither gullying nor markedly irregular relief. Instead, one sees evidence along the section of sheetwash events of silt removal from upslope […]2013, R. Dale Guthrie, Frozen Fauna of the Mammoth Steppe: The Story of Blue Babe: