Introduction - Geotechnics of Organic Soils and Peat - page 3

Figure 1.3 Laterite and saprolite profile: A represents soil; B represents laterite, a regolith; C rep-
resents saprolite, a less-weathered regolith; and D represents bedrock ( Source : http://en
.wikipedia.org/wiki/Laterite).
Saprolite, sometimes called 'rotten rocks', is a general term for residual soils that
are not extensively weathered and still retain much of the structure of the parent rock.
Laterite is a residual soil found in tropical regions. This type of soil is cemented
with iron oxides, which gives it a high dry strength (Figure 1.3).
The engineering properties of residual soils range from poor to good, and generally
improve with depth.
1.2.2 Glacial soils
Much of the Earth's land area was once covered with huge masses of ice in the form
of glaciers. These had a dramatic effect on the landscape and created a category of
soil called glacial soils. Glacier ice is not stationary but moves along the ground, often
grinding down some areas and filling in others. Glaciers grind down soils and rocks
and transport these materials over long distances, up to hundreds of kilometres. The
resulting deposit often contains materials from various sources. These deposits can