Pigeon House Mountain is on the South Coast between Ulladulla and Bateman's Bay and is a good example of an old volcano. Worth the climb for the views of the area but be prepared for a challenging ascent.
Australia is an ancient island and Aboriginal culture goes back 40,000 years. Geologists have dated rocks here that date back 4,400 million years! The Chinese may have mapped part of northern Australia in 1422 and Dutchman Willen Jansz in the Duyfken was the first European to land in 1606. With no precious metal ores or spices the Dutch stayed north in Indonesia and it was Captain Cook who charted the east coast in 1769. The First Fleet arrived in 1788.
Fossil evidence similarities with Africa, India and South America support the theory that these three continents were all once joined as the super continent Gondwana. There are rocks in Australia however that predate any others preserved on earth.
Australia is geologically relatively stable with no active mountain building or major fault systems. It is New Zealand that still has the active volcanoes. Australia 'sits' on the Indo-Australian plate and is moving northwards at 70 mm per annum. Doesn't sound much but is 15 metres in 200 years of white settlement and for the Aborigines it is 3 kilometres.
We have had earthquakes though, notably in Newcastle in 1989 and in north east Tasmania and around Aelaide. Australia is probably the lowest and flattest land mass on the planet. Mount Kosciusko at 2,228 metres is the highest mountain and the average height across our Great Southern Land is 330 metres.
The Great Divide is the spine that starts at Cape York and runs through Crookwell onto Victoria. It separates the short rivers flowing east to the Pacific Ocean longer river systems draining westwards across the plains. The Great Divide is about 150 km inland from the east coast and is typically 300-1600 m above sea level. There are basalt rock remnants exposed at Bega for example that date back over 40 million years. Our volcanic origins are visible at places like Pigeon House Mountain and elsewhere.
Daramalan does not have much basalt soil so pasture and forage crops are our best choice rather than broadacre crops. Crookwell is a big potato growing region though where soils are richer. The farm's alluvial river flat paddock is rich though and we will be planting alfalfa later in the year to establish a feed paddock for years to come.
Off to plant some turnips and ryegrass now so back soon!
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