Cape York Peninsula - Geography and Geology

Geography and Geology

The west coast borders the Gulf of Carpentaria and the east coast borders the Coral Sea. The peninsula is bordered on three sides (north, east and west). There is no clear demarcation to the south, although the official boundary in the Cape York Peninsula Heritage Act 2007 of Queensland runs along approximately 16°S latitude.

At the peninsula’s widest point, it is 430 km from the Bloomfield River, in the southeast, across to the west coast (just south of the Aboriginal community of Kowanyama). It is some 660 km from the southern border of Cook Shire, to the tip of Cape York. The largest islands in the strait include Prince of Wales Island, Horn Island, Moa, and Badu Island.

At the tip of the peninsula lies Cape York, the northernmost point on the Australian continent. It was named by Lieutenant James Cook on 21 August 1770 in honor of Prince Edward, Duke of York and Albany, a brother of King George III of the United Kingdom, who had died three years earlier:

"The point of the Main, which forms one side of the Passage before mentioned, and which is the Northern Promontory of this Country, I have named York Cape, in honour of his late Royal Highness, the Duke of York."

The tropical landscapes are among the most stable in the world. Long undisturbed by tectonic activity, the peninsula is an extremely eroded, almost level low plain dominated by mighty meandering rivers and vast floodplains, with some very low hills rising to some 800 m elevation in the McIlwraith Range on the eastern side around Coen.

The backbone of Cape York Peninsula is the Peninsula Ridge, part of Australia’s Great Dividing Range. This mountain range is made up of ancient (1,500-million-year-old) Precambrian and Palaeozoic rocks. To the East and West of the Peninsula Ridge lie the Carpentaria and Laura Basins, themselves made up of ancient Mesozoic sediments. There are several outstanding landforms on the peninsula: the large expanses of undisturbed dunefields at the eastern coast around Shelburne Bay and Cape Bedford-Cape Flattery; the huge piles of black granite boulders at Black Mountain National Park and Cape Melville; and the limestone karsts around Palmerston in the Cape’s far south.