Key concepts

Question 1

Give examples of the following landform classifications

Morphological
Genetic

Answer 1

Morphological (size, shape, composition, location)
EG Plateau, Basin, Ridge, Terrace

Genetic (Fluvial, Glacial, Weathering, Coastal)
EG Moraine ridge, river terrace, sinkhole, glacial trough

Question 2

Whats the difference between erosional and depositional forms

Answer 2

erosional - removal of material ( frost weathering)

depositional - addition of material (Scree slope)

Question 3

Briefly describe the functional approach

Answer 3

based on the identification and explanation of process-form links

Form - interpreted from mapping, lab experiments (analysis) and computer simulations (modelling)

Distribution and intensity of process is interpreted from distribution of forms (climatic geomorphology)

Equilibrium form to be restored after a disturbance by high magnitude

Question 4

Breifly describe the historical (evolutionary) approach

Answer 4

focuses on progressive changes in landscape through time

can be used to

• reconstruct past environments
• determine effects of future changes (landscape sensitivity)

recognises that landforms are transient, a stage in an evolutionary sequence operating on a very long timescale

Question 5

Why are landscapes different ?

Resistance - Force - Time

Answer 5

Resistance - mechanical strength and chemical composition of materials. RESISTANCE to weathering and erosion across earths surface

Land forming processes vary over time. many processes related to climate which varies over space

TIME - physical changes are only observable over a long time period.
prolonged action of a process can lead to sudden and spectacular change to a land form = THRESHOLD RESPONSE

Question 6

What are formative events and give examples

Answer 6

events which change the landscape by bringing about a recognisable and persistent response (their thresholds have been reached)

E.G.

• Floods sustained rainfall = landslides, debris flow, sinkhole formation)
• Earthquakes

Question 7

define:
- Post-event readjustment
- Form constant

Answer 7

post event readjustment periods of variable length which immediately follow each formative event, in which the landscape readjusts to its new state.

Form constant - periods of variable length which follow from periods of adjustment, when no change occurs (thresholds are not exceeded)

Question 8

What are the three fundamental factors of Selby’s model of the tempo of landscape evolution

Answer 8

1. The magnitude of formative events
2. The frequency of formative events
3. The time taken for the landscape to readjust to an event