Why is a bird- foot delta like that of the present- day Mississippi below New Orleans likely to change naturally toward one with the shape of an equilateral triangle like the upper- case, Greek letter delta (A)?
A)Present- day distributaries have higher gradients than potential new ones.
B)Potential, new, distributary channels have higher gradients, causing downcutting of the existing channels.
C)Increased sediment loads since the mid- nineteenth century have caused the major distributaries to be filled with sand.
D)Potential, new, major distributary channels have steeper gradients than existing channels.

Question

Quizplus · Accepted Answer

Potential new major distributary channels have steeper gradients than existing channels, which can lead to the formation of new channels and a more triangular delta shape.

Why Is a Bird- Foot Delta Like That of the Present-