Carnarvon Gorge is a spectacular natural wonder in the semi-arid heart of Central Queensland, 600 kilometres northwest of Brisbane. At its mouth the Gorge sits 600 metres below a basalt plateau. The boulder-strewn Carnarvon Creek winds through its 22 kilometre1 length. The Gorge sits at the junction of two major geological basins (See Figure 3 of Geological history of Carnarvon Gorge).

The towering walls of the Gorge expose sediments from the Surat Basin, which hosts abundant gas and oil reserves in other parts of the state. The most prominent feature in the Gorge is its brilliant, white cliffs of Precipice Sandstone—the lowermost member of the Surat Basin. Like a blanket, these sediments cover a large part of eastern Australia (See Sedimentary blankets). They were deposited towards the middle of Noah’s Flood as the waters were rising on the earth and nearing their peak (See Carnarvon Gorge geological history).

Sediments from the uppermost member of the Bowen Basin form the floor of the Gorge. Because the Moolayember Formation is relatively impermeable water from the springs of the Gorge remains close to the surface, making the Gorge an oasis in the arid country. The Bowen Basin extends to the north and east, and has rich coal deposits. This basin was also deposited during Noah’s Flood, earlier than the Surat Basin (See Carnarvon Gorge geological history).

Basalt caps, up to 300 metres thick, sit high above the gorge on either side. These are part of the Buckland Volcanic Province and form the Consuelo Tableland, atop the north wall, and the Great Dividing Range, to the south. Boulders eroded from the basalt dominate the waterways of the gorge. The hot basalt lava flowed across the sandstone plateau after the floodwaters had reached their peak and just started to recede from the continents. It was subsequently disected by the receding water. (See Carnarvon Gorge geological history)….

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