Australia, the world’s smallest continent and one of its largest nations, is located in the Southern Hemisphere between the Pacific and Indian oceans. Canberra, the capital of Australia, is situated between the larger and more significant economic and cultural hubs of Sydney and Melbourne in the southeast.
The Australian mainland stretches for nearly 2,500 miles (4,000 km) from west to east and for nearly 2,000 miles from Cape York Peninsula in the northeast to Wilsons Promontory in the southeast (3,200 km). Australian jurisdiction extends north to the southern shores of Papua New Guinea and south 310 miles (500 km) to the southernmost point of the island of Tasmania. The Timor and Arafura seas, the Coral Sea, and the Torres Strait separate Australia from Indonesia to the northwest, Papua New Guinea to the northeast, the Great Barrier Reef from the Coral Sea Islands Territory, the Tasman Sea from New Zealand to the southeast, and the Indian Ocean from Antarctica to the far south.
Australia has been referred to as “the Last Land,” “the Oldest Continent,” and “the Oldest Frontier.” These are typical descriptions of Australia’s fascination with the rest of the world, but they fall short in some ways. In plain physical terms, the age of much of the continent is impressive; the majority of the rocks that form the basis of Australian landforms were created between 4.6 billion and 252 million years ago. However, the cores of all continents are roughly the same age. On the other hand, whereas events and processes that took place since the end of the last Ice Age—roughly the past 25,000 years—have had a significant impact on the landscape history of large areas in Europe and North America, scientists in Australia use a longer timescale that takes into account the great antiquity of the continent’s landscape.
Australia is the last of the lands, but only in the sense that it was the last continent to be explored by Europeans, aside from Antarctica. The first Aboriginal explorers arrived from Asia at least 60,000 years before European explorers set sail for the South Pacific, and by 20,000 years ago, they had dispersed across the continent and Tasmania, the main island outlier. There may have been between 250,000 and 500,000 Aboriginal people present when Captain Arthur Phillip of the British Royal Navy and the First Fleet landed at Botany Bay in 1788, though some estimates are much higher. Contrary to common European perceptions, the Aboriginals—who were primarily nomadic hunters and gatherers—had already significantly altered the prehistoric landscape through the use of fire. They had also built strong, semipermanent settlements in advantageous locations.
the Australian flag
QUIZ ON BRITANNICA
Australian geography quick test
Australia’s length from east to west is just under 4,000 kilometres (miles). This quiz is much more condensed. See how soon you can circle Australia.
Dove Lake, Australia’s Tasmania
Dove Lake, Australia’s Tasmania
Also unsuitable is the American-style notion of a national “border” extending along a line of settlement. Instead, there were a number of expansions that came from the edges of the several colonies, which were not united as a free federated state until 1901. Frontier metaphors have been used for a long time to imply that Europe has yet another frontier, specifically one that is home to Anglo-Celtic civilization, in the far-off “antipodes.”
The vast nation’s low relief, global isolation, and aridity on much of its surface are its most striking features. Visitors from the Northern Hemisphere may initially be struck by the “vast, uninhabited land and by the grey charred bush…so phantom-like, so ghostly, with its tall, pale trees and many dead trees, like corpses,” like the English novelist D.H. Lawrence. However, they should keep in mind that to Australians, the bush—that sparsely populated Inland or Outback beyond the Great Dividing Range of mountains running along the Pacific coast and The Outback poem “Waltzing Matilda” by A.B. (“Banjo”) Paterson, which is regarded as the unofficial national anthem of Australia and is well-known around the world, still has some of the mystique that it had for the early explorers looking for inland seas and great rivers. It also still serves as a symbol of Australia’s strength and independence.
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Wonderful Barrier Reef
Wonderful Barrier Reef
The uniqueness of Australia’s plant and animal life can be partly explained by its isolation from other continents. Numerous varieties of eucalyptus trees and the platypus and echidna, the only egg-laying mammals on Earth, are among its distinctive flora and wildlife. Numerous acacias, including the national flower, Acacia pycnantha (often known as the “golden wattle”), as well as dingoes, kangaroos, koalas, and kookaburras, are other plants and animals that are related to Australia. The largest mass of coral in the world and one of the most popular tourist destinations worldwide is the Great Barrier Reef, which is located off the east coast of Queensland. The low relief of the land is a result of the long-lasting and widespread erosive activity of the wind, rain, and sun heat throughout the long geologic epochs when the continental mass was raised significantly above sea level.
Beyond the major coastal cities, isolation is a notable feature of much of the social landscape. A development resulting from immigration that is altering Australia’s strongly Anglo-Celtic orientation is the representation of a broad spectrum of cultures drawn from various lands, which is a feature of contemporary Australian society that is equally significant. Assimilation, of course, rarely happens quickly or easily, and current Australian politics have been heavily influenced by issues of multiculturalism, minority rights, and racial discrimination. These problems led to a conservative backlash in the late 1990s.
Australia has a federal system of government, with separate state governments and a national government for the Commonwealth of Australia (those of New South Wales, Victoria, Queensland, South Australia, Western Australia, and Tasmania). Each state has a constitution, and each one’s government only has a certain amount of sovereign power. There are also two internal territories: the Australian Capital Territory (which includes the city of Canberra), which became self-governing in 1988, and the Northern Territory, which became self-governing in 1978. The Australian Antarctic Territory, a region larger than Australia itself, is claimed by the federal government and includes the external territories of Norfolk Island, the Cocos (Keeling) Islands, Christmas Island, the Ashmore and Cartier Islands, the Coral Sea Islands, and Heard Island and McDonald Islands. Formerly an Australian overseas territory, Papua New Guinea attained independence in 1975.
Australia is an independent nation that was once a part of the British Empire and is currently a member of the Commonwealth. Australians are fortunate in many ways because no other country shares their continent, which is only marginally smaller than the United States. Australians have grown more interested in the region’s huge potential markets in Asia and the fiercely competitive industrialised economies of China, Japan, South Korea, and Taiwan. Despite being extremely remote from their traditional allies and trading partners—it is approximately 12,000 miles (19,000 km) across the Pacific Ocean and the Suez Canal from Australia to Great Britain and approximately 7,000 miles (11,000 km) across the Indian Ocean to the west coast of the United States—and their traditional trading partners. Australia, the continent and the nation, may have been relatively remote at the start of the 20th century, but it entered the 21st century as a culturally diverse country full of confidence. This attitude was encouraged by the global fascination with “Down Under,” which was on display when Sydney hosted the 2000 Olympic Games.
historical geology
Detrital zircon grains found in metasedimentary rocks that were deposited between 3.7 and 3.3 billion years ago are the earliest known examples of the geologic history of the Australian continent. They are 4.4 billion years old. Based on those and other discoveries, it has been concluded that the Precambrian rocks in Australia are between 3.7 billion and 541 million years old (i.e., to the end of Precambrian time). They are followed by rocks from the Paleozoic Era, which began approximately 252 million years ago and lasted until 66 million years ago, the Mesozoic Era, which lasted until 66 million years ago, and the Cenozoic Era, which began 66 million years ago.
Australia was once a part of the supercontinent Pangaea and later its southern region, Gondwanaland, for millions of years (or Gondwana). The final link between Tasmania and Antarctica was severed, ensuring its independence, yet it has been moving toward the Southeast Asian landmass. Australia as a continent thus encompasses two extremes: on the one hand, it contains the oldest known earth material; on the other hand, it has only existed as a free continent for a short period of geologic time—about 35 million years—and is currently merging with Asia, meaning that its life span as a continent will be relatively brief. (See also Earth’s geologic history.)
common sense considerations
Tectonic structure
Australia’s Northern Territory’s MacDonnell Ranges
Australia’s Northern Territory’s MacDonnell Ranges
The distribution of the major tectonic units is depicted on the map of Australia’s structural features and the area around it. The main distinction is between the continental lithosphere, which has accumulated over the past 4 billion years, and the plates of oceanic lithosphere, which were produced within the last 160 million years by seafloor spreading along the oceanic ridges. (See plate tectonics.) The lithosphere, the planet’s outer rock shell, is made up of the crust and the uppermost layer of the mantle beneath it. The Western Shield, which makes up the western half of the continent and has been eroded to a low relief, contains the majority of the oldest rocks. The youngest rocks can be found in New Guinea near the meeting point of the Indian-Australian plate and the Eurasian and Pacific plates as well as in the expanding fold belt of the Banda arcs. A “moat” (the Timor Trough) and a large shelf separate Australia from the present fold belts (the Timor and Arafura seas). The Great Barrier Reef and the Queensland Plateau on the east and the North West Shelf and Exmouth Plateau on the west respectively complete the northern half of the Australian margin.
Australia’s Tasmania and Cradle Mountain
Australia’s Tasmania and Cradle Mountain
Precambrian rocks are found in three tectonic settings. The first is in shields, like the Western Shield’s Yilgarn and Pilbara blocks, which are encircled by more recent orogenic (mountain) belts. The second is as the basement to a newer layer of Phanerozoic sediment (deposited over the last 541 million years); for instance, Precambrian basement underlies all sedimentary basins west of the Tasman Line. The third type of orogenic belt is found as remnants in newer orogenic belts, such as the Georgetown Inlier in northern Queensland and the western half of Tasmania. Paleozoic rocks can be found in belts like the east-west trending Amadeus Transverse Zone and the north-trending Tasman Fold Belt, or in flat-lying sedimentary basins like the Canning Basin.