Dating bathurst nsw
In the later Tertiary the Basin began to subside, resulting in the internal (endogenetic) drainage system that drains much of inland Australia.
Depositional plains are also a prominent feature of inland Australia (Twidale & Campbell, Source 5).
By the time the water table gets close to the surface it has passed through these salt layers and so causes salinisation in the root zone and eventually at the surface, which makes the land useless for agriculture.
Landforms The geologic history and its climatic contrasts are reflected in the landforms.
It is the driest, flattest, oldest, it has the most erratic climate of any continent, and much of it experiences great extremes of rainfall both during a year and from year to year.
As a result of this, poor soil, arid and unpredictable climate over most of the continent, the plants, and therefore the animals that depend on them, have evolved into a unique flora and fauna.
There are not many areas above about 1700 m, and even at Mt Kosciusko, the highest point on the continent, it is less then 3000 m above sea level.
Not high compared with the mountains in other parts of the world. There have been many episodes of warping and faulting, that were widespread but minor, since the orogenesis that produced the Eastern Highlands.
So added to this impoverished state of the soils there are vast areas where there are salt deposits beneath the surface which means when land is cleared for agriculture the removal of deep-rooted trees and shrubs mean the water table rises.It is only in very wet years that the water reaches all the way to Lake Eyre, especially as a lot of the water is absorbed into the dry channel beds and evaporates in the hot dry air of the interior long before it reaches Nearly all of the area inland of the peripheral drainage systems generates less the about 3 cm per year of run-off.As aridity has increased any rivers that had existed on the low gradient sandy surfaces of the shield areas have disintegrated or disappeared entirely.During this time period Australia had After being recycled many times over much of the history of the Earth, with no new rock added by volcanism, the soils of arid Australia have been weathered and leached more than any others making them the most nutrient-deficient soils in the world.And most of Australia spent many millions of years covered by seas.