Which mechanism dictates terrace formation due to cyclical base-level changes along an alluvial river?

💡 Explanation

When base level fluctuates, alternating incision and aggradation occur because lowering base level causes the river to cut down, while raising shifts deposition, forming a new floodplain at a lower level. Therefore cycles of fluvial incision/aggradation create terraces, rather than differential weathering, rebound, or faulting which involve different drivers.

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