||Relief is defined as the difference in elevation between the high and low points of
a land surface. Its estimation will be made easier by visualising two surfaces of
accordance that are planar or gently curved, one touching the major crests of a landform
pattern, and the other passing through the major depressions. The average vertical
separation of the two surfaces is a measure of the relief. Make this estimation at
a field site, either visually or by using a map, and express it in metres.
Relief is the definitive characteristic for the terms mountains, hills, low hills,
rises and plains when used as types of erosional landform pattern (Table 5). The class
boundaries, shown in Tables 5 and 6, are set at 300 m, 90 m, 30 m and 9 m. These class
limits and the class names are similar to those used by Löffler (1974), and are broadly
compatible with those of Löffler and Ruxton (1969).
Table 6 lists types of landform pattern defined in the glossary according to their
typical relief class. Those types for which the relief class is definitive are in