Atherton Plateau
The Atherton Plateau has an area of about 13,000 square miles above the 2000-foot contour line, and the highest point reaches 5438 feet in Mt. Bartle Frere. The elevation of the Atherton Plateau makes its climate much more attractive than that of the adjacent lowlands. The plateau rises precipitously from the narrow coastal plain, and deep gorges have been cut into its eastern margin by the Barron, Mulgrave, and Russell rivers.
New England Plateau
The New England Plateau has an area of about 23,000 square miles above the 2000-foot contour, and Ben Lomond and several other knobs approach 5000 feet in elevation. The Darling Downs in Queensland include about 5000 square miles above the 2000-foot contour just across the state boundary. The highest margin of the New England Plateau faces the sea, and its margin has also been deeply carved by the Macleay, Manning, and Bellinger rivers. The narrow coastal plain is crossed by those streams in their quick descent to sea level. The New England Plateau, like the Atherton Plateau, is comprised principally of granites, but volcanic materials have been ejected in numerous places. A narrow coastal plain lies along the eastern margin of the New England Plateau.
Blue Mountain Plateau
The Blue Mountain Plateau rises to a height of 3000 to 4000 feet, and it has about 15,000 square miles above the 2000-foot contour. Although the plateau makes direct contact with the interior somewhat difficult, residents of Sydney make full use of the upland for resort purposes. The Grose and Cox rivers have cut spectacular bottleneck valleys into the steeply rising eastern flank of the upland. Vertical sandstone cliffs 1000 to 2500 feet in height make these broad, flat-floored valleys useless as approaches to the plateau surface.
The coastal belt to the north and the south of Sydney has been uplifted in places as much as 500 to 1000 feet, and streams have carved gorges with intricate patterns. Subsequent drowning has made the lower courses of these rivers useful for harbors, as at Sydney and Jervis Bay. The Illawarra coastal plain, 50 miles south of Sydney, provides a suitable lowland for agricultural development and for industrial sites.
Although the Blue Mountain Plateau lies athwart Sydney's direct route into the interior, suitable gaps at the north and south ends of the plateau are available. The Hunter River valley provides an easy route to the west from Newcastle, and near Goulburn the railroad passes around the southern end of the Blue Mountains.
Monaro Plateau
The Monaro Plateau is on the New South Wales-Victoria border. About 13,000 square miles lie above the 2000-foot contour line. It is the highest upland region in Australia, and several peaks rise above 6000 feet with Mt. Kosciusko reaching 7328 feet. Several thousand square miles of the Monaro Plateau lie above the 5000-foot elevation and provide a readily accessible tract of snow-covered country for winter sports during the months of June to September. The most important rivers of the continent rise in this high southeastern plateau region. The Commonwealth Federal Territory is situated on the northern margin of this upland at an elevation of about 2000 feet.
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