4. River Morphology

Charlton 2008, Fundamentals of Fluvial Geomorphology

Bedrock Channels

incising into bedrock

bedrock channel landforms:

• steep Zone 1 channels

• canyons/gorges

• waterfalls

• incised meanders

Alluvial Channels

flow through their own deposits (alluvium)

Charlton 2008, Fundamentals of Fluvial Geomorphology

classify alluvial channels by sediment load:

• bed load: steep slope; wide and shallow cross-section; step-pool or braided pattern

• mixed load: intermediate slope and cross-section; wandering or meandering pattern

• suspended load: gentle slope; narrow and deep cross-section; low-sinuosity, meandering or anastomosing pattern

Charlton 2008, Fundamentals of Fluvial Geomorphology

1 km

5 km

Charlton 2008, Fundamentals of Fluvial Geomorphology

1 km

10 km

50 km

1 km

1963

1954

Charlton 2008, Fundamentals of Fluvial Geomorphology

10 km

Para

guay

Rive

rParana River

Bermejo River

1 km

Alluvial-Bedrock Channels

10 km

Zone 3: Alluvial Fans and Deltas

alluvial fan: a fan-shaped mass of sediment

• deposition: sediment from a river and/or debris flows

• debris flow: moving mass of loose mud, sand, soil, rock, water and air that travels down a slope under the influence of gravity.

1 km

delta: deposit of sediment formed as a river enters standing water

LillooetFraser

WilliamMekong

30 km

1 km

10 km

10 km

50 km