A number of sedimentary structures have been recorded in a channel island in the Barakar River. In order of abundance these are as follows: cross-stratification, horizontal stratification, sand wave. ripple-drift laminae. deformational structures, current crescent, and ripple-mark. A vertical variation has also been noted in the occurrence and abundance of these structures. The island is thought to have originated as a point bar which was later converted to a channel bar and finally to a channel island.