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A sinuous ridge is a thin and meandering formation that gives the appearance of a stream channel, but stays raised above the surface rather than incised into it. It is believed that these ridges were once stream channels that cut down into the surface. Flowing water can have a number of effects on a channel bed, such as sorting grains and depositing rocks, all while removing loose material. The water can also carry a number of dissolved minerals that become deposited and cement the remaining grains together. The result is a stream bed that has become "armored." Once the stream stops flowing …
