Which process causes sorted sediment deposition on an alluvial fan during sheet flooding events?

💡 Explanation

When overland flow decelerates across an alluvial fan, flow competence decreases because sediment carrying capacity reduces as slope declines radially, leading to deposition of coarser material upstream and finer material further downslope. Therefore decreasing flow competence results, rather than incision, stabilization or weathering which involve different factors.

• Which mechanism causes increased coastal desertification when a major ocean gyre weakens?
• Which consequence results when lava's rheological properties change?
• Which process limits the formation of mature braided streams on steep alluvial fans in arid climates?
• Which mechanism causes the formation of large pluvial lakes during glacial periods?
• Which mechanism primarily leads to the formation of an oxbow lake cutoff?
• Which topographical outcome consistently follows alluvial sediment deposition?