Which outcome arises when sediment accumulates rapidly on an alluvial fan at a tectonic basin margin?

💡 Explanation

When rapid sedimentation occurs, base-level in the proximal alluvial fan rises, leading to a temporary flattening of the gradient and eventually triggering stream incision and creation of terraces as the system adjusts to the new base level. Therefore stream incision results, rather than weathering decrease, porosity increase, or prohibited lithification which require different geological conditions.

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