Sydney Basin

Sydney Basin New South Wales
Map of the Sydney Basin
The interim Australian bioregions, with the Sydney Basin in red
Coordinates	33°56′53″S 150°45′36″E / 33.94806°S 150.76000°E / -33.94806; 150.76000
Population	6,300,000[1]
• Density	173.6/km2 (450/sq mi)
Area	36,295.97 km2 (14,014.0 sq mi)[2]
Mean max temp Mean min temp Annual rainfall[1]  ? ? 650−1,300 mm 598.8 in
Localities around Sydney Basin: South Eastern Highlands North Coast Tasman Sea South Eastern Highlands Sydney Basin Tasman Sea Australian Alps South Coast Tasman Sea

The Sydney Basin is an interim Australian bioregion and is both a structural entity and a depositional area, now preserved on the east coast of New South Wales, Australia and with some of its eastern side now subsided beneath the Tasman Sea. The basin is named for the city of Sydney, on which it is centred.

Around 5,000 metres (16,000 ft) thick, the Sydney Basin consists of Permian and Triassic sedimentary rocks, which stretches from Newcastle in the north to Batemans Bay in the south, and west to the Great Dividing Range. The basin is also home to the major centres of Newcastle, Gosford, and Wollongong, as well as the state capital of Sydney, and contains economically significant reserves of coal.

Sydney's famous harbour and the sculptured cliffs of the Blue Mountains are signature formations of relatively hard upper strata of sandstone. The basin contains the UNESCO World Heritage-listed Greater Blue Mountains Area.^[3]