Page 194 - Fundamentals of Geomorphology

HILLSLOPES 177

100
a
() Initial form at start of
postglacial period
(m)
Elevation
50
0
100
b
() Form after no cliff retreat
and 10,000 years of
basal accumulation
50

0
100
c
() Form after 2,000 years of cliff
retreat and then 8,000 years
of basal accumulation
50

0
100
d
() Form after 4,000 years of cliff
retreat and then 6,000 years
of basal accumulation
50

0
100
() Form after 6,000 years of cliff
e
retreat and then 4,000 years
of basal accumulation
50

0
100
() Form after 8,000 years of cliff
f
retreat and then 2,000 years
of basal accumulation
50

0
250 200 150 100 50 0
Distance (m)
Figure 7.8 Kirkby’s modelled hillslope profiles for South Wales cliffs during the postglacial period. The model
assumed basal retreat of 20 mm/yr for the first 8,000 years and basal accumulation for the last 2,000 years.
Source: Adapted from Kirkby (1984)