Sedimentation on the channel banks in a multi-channel river system
1991
Alam, M.M.
Deposition within the streams of a multi-channel river in Australia develop three distinct bench levels : lower (LB), middle (MB) and upper (UB), which appear unlike terraces or laterally accreting point bars. Bench development is related to some constant parameters of stream-flow and sedimentation. Rate of vertical and lateral accretion of benches depends on their elevation above stream bed and depositional site. Lower bench deposits are mainly cross-bedded sand, often mud draped. Deposits of middle and upper benches comprise interbedded sand and mud. Sand beds are parallel, wavy-, and ripple-laminated; and mud beds contain roots and desiccation cracks. Bench deposits are characteristic of modern streams and paleochannels in diverse setting. Hence, data on the development and style of bench sedimentation may be valuable in paleofluvial studies.
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