The work of the wind - Fundamentals of the Physical Environment - page 520

more conventional, desert origin in continental-interior cooler mid-latitudes. Loess rarely
develops clearly defined dune bed forms and forms a blanket cover of the existing
topography instead over some 10 per cent of global terrestrial surfaces (see Figure 1). Silt
and clay particles, together with the cementing effect of deflated carbonate-rich parent
rocks or desert evaporites, develop stabilizing cohesion.

Figure 1 Global loess deposits. Note the focus around 40° latitude
north and south, between the subtropical high-pressure belt and
Pleistocene ice limits.
Source: After Livingstone and Warren (1996).

In North America, loess deflated from the Rocky Mountains and margins of
Laurentian ice lobes in the Great Lakes region blankets much of the high plains west of
the Missouri river and is funnelled into the Missouri-Ohio-Mississippi basin. Loess
forms an extensive apron fringing Fennoscandian Pleistocene ice limits in Europe and the
smaller, mountain icefields and frost deserts of Siberia. Southern hemisphere deposits are
limited to extensive sheets between the Andes and the river Paraná in Argentina and the
Southern Alps and east coast in New Zealand. There is no great thickness to any of these
loess sheets, which vary generally from about 0 m to 40 m, but they often provide
valuable cereal-growing soils, and the

designation brickearth in some areas indicates their local importance to brick
manufacture. British loess deposits, concentrated in south-east England, scarcely reach 2
m thick

largely because of erosion by rising sea levels along the North Sea coast as