History of Tasmania
Tasmania was inhabited by an indigenous population, the Tasmanian Aborigines, and evidence indicates their presence in the territory, later to become an island, at least 35,000 years ago. At the time of the British occupation and colonisation in 1803 the indigenous population was estimated at between 3000 and 10,000. Historian Lyndall Ryan's analysis of population studies led her to conclude that there were about 7000 spread throughout the island's nine nations; Nicholas Clements, citing research by N.J.B. Plomley and Rhys Jones, settled on a figure of 3000 to 4000. The combination of the so-called Black War, internecine conflict and, from the late 1820s, the spread of infectious diseases to which they had no immunity, reduced the population to about 300 by 1833. Almost all of the indigenous population was relocated to Flinders Island by George Augustus Robinson. Until the 1970s, most people thought that the last surviving Tasmanian Aborigine was Trugernanner, who died in 1876. However this "extinction" was a myth, as documented by Lyndall Ryan in 1991.
Geology of Tasmania
The earliest geological history is recorded in rocks from over . Older rocks from western Tasmania and King Island were strongly folded and metamorphosed into rocks such as quartzite. After this there are many signs of glaciation from the Cryogenian, as well as the global warming that occurred at the start of the Ediacaran period. An orogeny folded the older Precambrian rocks. In the Cambrian time the Tyennan block forming the south west and central Tasmania, was pushed up and slightly over the land of north west Tasmania, the Tyennan Orogeny. Then there were volcanic action and sediments from the Cambrian and Ordovician. The large ore deposits were formed on the West Coast. The north east of Tasmania began to form as part of the Lachlan Orogen with turbidity flows of mud and sand on to the ocean floor. In the Devonian the Tabberabberan Orogeny caused more folding, and intrusion of granite on the west and east coasts, and probably joined the east of Tasmania to the west.