SCALE PROCESSES

SCALE PROCESSES

LARGE SCALE

MEDIUM SCALE

SMALL SCALE

Hydrological

Biogeographical

Geomorphological

Process of building up the land. Operates to work produce geological foundations to be eroded by water. (Waitakere Ranges.)

Processes related to the water cycle. These operate/work to produce and move water, the main agent of fluvial erosion, fluvial transportation and fluvial deposition in the PRDB.

Processes influencing plant life & growth. Operate to produce vegetation influencing the level of fluvial processes outside and within the river channel of the PRDB (Glen Esk Stream, Piha River.)

Fluvial Deposition

Uplifting

Fluvial Transportation

Faulting

Fluvial Erosion

Volcanism

The wearing away of the land through the action of water; rivers and streams. Can occur inside and outside of the stream channel. (1400-2000mm Rainfall, Piha River & Glen Esk Stream.

1) Water hits soil & rock over time.
2) Force dislodges soil/rock, particles become looser.
3) Particles fall away = changed surface/rock.

Eroded sediment is moved, through the action of water & rivers. Moves material into the stream channels & eroded sediment is then transported to the PRDB stream channels to be deposited.

1) Soil and rock eroded enters stream channel.
2) Soil and rock collected by water flow.
3) Soil and rock moved within the stream channel, by small scale processes.

Eroded material is put down/deposited through rivers and streams (Piha River, Glen Esk Stream.) Operates to put sediment on the stream bed and to build the Piha River Floodplan.

1) Soil and rock transported in the stream channel.
2) Velocity of water reduces therefore soil and rock sediment cannot be carried.
3) Soil and rock sediment is deposited to build up point bars, floodplains & sediment on the stream bed.

All operate together to produce the geological foundations of the PRDB, that are eroded by the fluvial erosion processes operating outside, and within the stream channels of the Piha River and Glen Esk Stream.

Fluvial Erosion:

Fluvial Transportation:

Fluvial Deposition:

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