The Victorian Alps, closely associated with the Monaro Plateau, include about 8000 square miles of moist mountain land above the 2000-foot contour. General elevations are similar to those of the Monaro Plateau.
The extensive coastal lowlands of Victoria lie on the south side of the Monaro Plateau and its western upland continuation. The Victoria lowland stretches for more than 150 miles to the east of Melbourne as the Gippsland district, and as far to the west in the form of a basalt-covered plain. A convenient gap at Kilmore in the east-west segment of the highland enables Melbourne to tap the Murray basin. Port Phillip Bay represents the drowned middle portion of the Victorian lowland, and at its head is situated the city of Melbourne.
Tasmanian Land Forms
Tasmania, although separated from the mainland by Bass Strait (about 150 miles in width), is essentially an outlier of the Eastern Highlands. The dominant feature of the island is the western plateau, which attains a general height of about 3500 feet. About 4000 square miles lie above the 2000-foot contour. Several peaks rise from its western and southern margins to heights of nearly 5000 feet, and Mt. Cradle attains a maximum of 5069 feet. Although the margins of the plateau are deeply dissected, the central portion consists of an old undulating surface. Several large natural lakes occur on the upland, among them Lake Sorell and Great Lake, that are the source of the island's hydroelectric power.
The plateau descends on the east by a series of step faults ("tiers") to a central lowland. Launceston is situated near the north end of this lowland, and Hobart, on the Derwent River estuary, is at the southern end. The eastern margin of the island is occupied by ranges of mountains, which in the northeast corner exceed 5000 feet in height. The eastern highland merges with the western plateau at Oatlands in a range of hills that separates the drainage of the Derwent River from that of the Tamar River.
Coastline in Eastern Australia
The coastline associated with the Eastern Highlands and Tasmania consists of alternating rocky headlands and sandy beaches or embayments. In many places narrow coastal plains lie between the surf and the uplands, and numerous rivers have been drowned in their lower courses. Islands are numerous in the shallow Bass Strait and also along the Queensland coast, where coral reefs help to preserve them.
The Great Barrier Reef of Queensland is the most notable shoreline feature of Australia. The reef and associated islands extend for 1250 miles from a point off Rockhampton to Torres Strait. The reef lies more than 100 miles offshore at the southern end, but it approaches within a few miles of the mainland along much of its northern portion.