Knowra River delta River delta A landform formed as a river deposits sediment where it enters a slower-moving body of water. Its channels divide into distributaries that spread sediment across the delta.
Sediment deposition : The settling and accumulation of particles carried by water, wind, ice, or gravity. As river flow slows at its mouth, suspended sediment settles and builds delta land.
Sediment transport : The movement of mineral and organic particles by flowing water, wind, ice, or gravity. Rivers carry the material that becomes delta deposits.
Nile Delta : The broad, fan-shaped delta where the Nile River reaches the Mediterranean Sea. Its shape gave the landform its name, from the Greek letter delta.
Delta subsidence : The gradual sinking of delta land through sediment compaction, fluid extraction, or tectonic movement. Subsidence lowers delta surfaces and increases their exposure to flooding.
Alluvial fan : A fan-shaped deposit formed where a stream leaves a steep valley and spreads across flatter ground. Both landforms spread sediment, but an alluvial fan forms on land rather than in a receiving water body.
Distributary : A channel that branches away from a river's main course and flows toward its mouth. Delta growth splits river flow among these branching channels.
River mouth : The place where a river flows into another body of water. A river delta develops at this transition from river flow to receiving water.
Mississippi River Delta : A series of sedimentary lobes at the mouth of the Mississippi River in Louisiana. Its changing lobes illustrate how river channels shift and abandon coastal areas.
Relative sea-level rise : An increase in sea level relative to the land at a particular location. It combines ocean rise and sinking land to measure a delta's changing coastal water level.
River-dominated delta : A delta whose shape and sediment distribution are controlled mainly by river discharge. This subtype contrasts with deltas reshaped more strongly by waves or tides.
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