Question

Where do deltas form?

Multiple choice question.
a) Downstream of dams in channelized sections of a stream
b) Right below a nickpoint in a braided river system
c) Right above a nickpoint in a meandering river system
d) At the mouth of a river that empties into the ocean

Answer 1

Deltas form at the mouth of a river where it empties into an ocean or large lake, as the silt and sediment carried by the river settles due to the reduced water flow.

Step-by-step explanation:

Deltas form at the mouth of a river that empties into the ocean. When a river reaches a larger body of water like an ocean or a large lake, the water flow slows significantly, allowing the silt and sediment carried by the river to settle. An environment characteristic of deltas is one where rivers with high silt content discharge into regions with minimal ocean currents and wave action, which enables the formation of low-elevation land areas made of sand and mud. A delta is essentially a deposit of sediment that accumulates over time, often creating a triangular-shaped section of land as the river splits into many channels before it joins the larger body of water.

An example of a delta would be the Mississippi River delta, which extends from New Orleans to the Gulf of Mexico. This delta has formed where the freshwater of the Mississippi mixes with seawater, causing colloidal clay particles in the river water to precipitate, and this area is clearly visible in satellite photographs.