There is a delta at the mouth of the Mississippi River. What process caused this buildup of sediment? erosion friction mechanical weathering chemical weathering deposition

deposition

Explanation:

The correct answer would be deposition.

Generally, deltas are structures that are formed when a body of water empties its contents into another body of water, usually a larger one.

While the water goes into the larger water body, the sediments being carried by the water are deposited at the mouth of the larger water body and an over-the-time accumulation of these sediments results in a landform known as delta.

the answer to you question is   jet streams