Which mechanism causes increased sediment deposition in the cutoff area of a forming oxbow lake?

💡 Explanation

When a river cuts off a meander bend to form an oxbow, a shorter, steeper channel path develops, thus flow velocity decreases drastically in the abandoned meander because overall gradient favors the new channel. As a slower velocity will carry less sediment as per Stokes' law. Therefore, increased sedimentation occurs, rather than slope change, instability, or hydraulic enhancement, which would require external forcing like tectonic shifts, accelerated erosion and/or flooding events.

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• Which limit constrains the formation of extensive alluvial terraces in a rapidly uplifting mountain range?
• Which outcome results from the Coriolis effect on large-scale ocean currents moving away from the equator?