Which depositional pattern develops when a mountain stream abruptly enters a broad, dry valley?

💡 Explanation

When a steep mountain stream enters a flat valley, a sudden decrease in stream gradient causes a loss of carrying capacity leading to sediment deposition in an alluvial fan because flow diverges and slows. Therefore, sorted alluvial deposition occurs, rather than braided channels, floodplains or deltas, which involve different topographic and fluid dynamics parameters.

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