Types of Delta

There are four main types of deltas which are classified by processes that control the buildup of silt:

Wave Dominated Deltas
Tide Dominated Deltas
Gilbert Deltas
Estuarine Deltas

Deltas are also categorized into three main groups which are named after the shape that they create.

Arcuate Delta

These three images below have been created through the use of data downloaded from the GCLF website. The layers have then been unzipped and through of the ERDAS programme they have been layer stacked. To clearly show the features of the three different shaped deltas the band combinations have been changes to RGB 453. This makes the water to land change very obvious so that the waters path can be seen therefore highlighting the shape.

This is the most common delta. It is fan shaped where the land around the river mouth arches out into the sea. The river splits many times on its way to the sea creating the fan effect.

Nile Delta, Egypt

Cuspate Delta

At this type of delta the material spreads evenly on either side of the estuary. The land around the mouth of the river juts out into the sea. It has often been described as an arrow like shape.

Ebro Delta, Spain

Birds Foot Delta

The Bird Foot delta is where the river splits various times on the way to the sea, each part of the river juts out in different directions. It is typically in the pattern of a bird's foot hence the name. This delta formation is usually associated with finer sediment.

Mississippi Delta, Louisiana, USA

(National Geographic Education)