Along with continental drift, Plate tectonics provides the evidence that Australia was once part of an ancient super continent. The theory of continental drift suggests that as the continents drift apart magma wells up through the spreading floor and new crust is formed.
There are 7 large plates and many smaller plates that drift around the surface of the earth. When these plates rub or bang together they causes earthquakes, and this is how mountains and deep trenches are formed on earth.
An example of this, is Antarctica. Antarctica wasn't always frozen, in fact it has been habitable for most of the earth's history. Before then Antarctica used to be connected to South America, and it was possible to walk there from Australia.
The distribution of mammals, especially the marsupials provides evidence for plate tectonics and the past of Gondwana. When Australia and Antarctica separated from Africa around 150 million years ago, Australia became isolated and the marsupials evolved and diverse species grew.
The Australian plate is moving northwards at about 3 cm per year. Volcanoes and earthquakes all provide evidence for the Earth’s continually wandering continents, as they generally occur along the margins of plates
There are 3 primary types of Tectonic Plate boundaries: Divergent boundaries; Covergent boundaries; and Transform boundaries. As the giant plates move, diverging [pulling apart] or converging [coming together] along their borders, tremendous energies are unleashed resulting in tremors that transform Earth’s surface.