Which feature is formed by the coalescing of several alluvial fans into a broader depositional apron?

Which feature is formed by the coalescing of several alluvial fans into a broader depositional apron?

• A. Pediment
• B. Bajada
• C. Mesa
• D. Alluvial fan

Answer: (B)

When several sediment-filled fans along a mountain front grow and their deposited sediments meet, they merge into one broad, continuous apron at the base of the range. This merging of multiple fans creates a wide, sloping deposit known as a bajada, or fan apron, formed as streams periodically flood from canyons and spread out, losing energy and depositing material along the base with each event. A pediment, by contrast, is a gently sloping bedrock surface carved and worn smooth at the base of mountains, not built up from fan deposits. A mesa is a flat-topped, elevated landform carved by erosion from a surrounding tableland. An alluvial fan is a single fan-shaped deposit at a canyon mouth, not the merged, broad apron that results from multiple fans coalescing.

When several sediment-filled fans along a mountain front grow and their deposited sediments meet, they merge into one broad, continuous apron at the base of the range. This merging of multiple fans creates a wide, sloping deposit known as a bajada, or fan apron, formed as streams periodically flood from canyons and spread out, losing energy and depositing material along the base with each event. A pediment, by contrast, is a gently sloping bedrock surface carved and worn smooth at the base of mountains, not built up from fan deposits. A mesa is a flat-topped, elevated landform carved by erosion from a surrounding tableland. An alluvial fan is a single fan-shaped deposit at a canyon mouth, not the merged, broad apron that results from multiple fans coalescing.