Australia: The Land Where Time Began

A biography of the Australian continent 

The Darwin Crater formed abut 820,000 years ago when a meteorite impacted western Tasmania, creating the silica glass called Darwin Glass. It has been estimated that the patchy distribution of the ejecta covered an area of about 400 m². At present, lake sediments of Pleistocene age overlie 230 m of breccia in the crater. The zone of about 2 km wide around the crater has the highest concentration of Darwin Glass, and in the 50 km² area around the crater there is estimated to be about 20,000 tonnes of this material. Darwin Glass has been used for tools and personal decoration by the Aboriginal people of Tasmania since the early days of their presence on the island, and it was widely traded in Tasmania. Darwin glass can be white, black, and light to dark green, and takes many forms such as twisted masses, fragments or formless chunks, and can be up to 10 cm long. In the interior of the chunks the texture can be flowing, defined by lines of gas bubbles.

The pollen cores from Darwin Crater contained pollen indicating the presence of cool temperate rainforests, especially Nothofagus, in wetter times during interglacial phases (Colhoun & Van der Geer, 1988). During the glacials the forests were replaced by open sclerophyll woodland and treeless herbfields and grasslands.

• The Moist Tropics
• Southeastern Australia
• The Arid Zone
• The Carpentaria Plain - New Lands
• The Bassian Plain

Australian Pollen Record

Sources & Further reading

1. Mary E. White, The Greening of Gondwana, the 400 Million Year story of Australian Plants, Reed, 1994
2. Chris Johnson, Australia's Mammal Extinctions, a 50,000 year history, Cambridge University Press, 2006
3. The Tasmanians: Part 8b: Archaeology and the Oldest Tasmanians