The Grange 
Geology
Geological History of The Grange
The Grange and the Ice Age
The Grange is located in the part of the south eastern suburbs of
Melbourne, often referred to as the sand belt region. This is so
called because of the sandy nature of the soil. The
soil
profile has been shaped over thousands of years.
During the last Ice
Age, approximately 20,000 years ago, the expanding polar ice-caps
locked up large quantities of water, which lowered the sea level. The
receding water levels drained Port Phillip Bay. Cold, dry winds swept
across the exposed sea bed to form sand dunes on the higher ground
which is now located on the eastern side of the Bay, including the
area in and around The Grange. When the Ice Age ended, about 9,000
years ago, the sand in these dunes began to change into the soils
they are today.
Soils of Ancient Sand Dunes
The sandy soil is now open and free draining, with water moving
through from crests
to swales.
The water takes the organic matter with it, which then concentrates in
the low-lying areas. This means that the crests are kept poor in nutrients
whilst the swales become relatively rich.
Organic matter allows soil to
increase the amount of water it holds, so the swales are relatively moist.