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The moods of Mallacoota change with the time of day and the season of the year. The subject of many a photographer's efforts and the stuff of picture-postcards, this is why many people come to reside or holiday in Mallacoota. Sunset on the Bottom Lake, with salt marsh islands in the foreground and the Howe Range in the background. Reflections in The Narrows, a short stretch of water connecting the two lakes of the Mallacoota Inlet system. Stormy weather batters the shore platform at Bastion Point. The Howe Range rises from the misty waters. |
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Mallacoota Inlet is found in the southeastern corner of Australia. It consists of the Bottom Lake and the Top Lake, here seen from Genoa Peak. The Goodwin Sands, an area of small islands and inter-tidal sands, can be seen in the Bottom Lake. The Howe Range, the freshwater Barracoota Lake and Bass Strait are in the distance. The land surrounding the lake system is included in the Croajingolong National Park, which stretches from the Vic-NSW border to Sydenham Inlet. |
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The view from Howe Hill reveals much about the formation of Mallacoota Inlet. The lakes were formed when rising sea levels flooded the Genoa River valley and pushed up a barrier of sand across the mouth of the new embayment. Later an outer barrier developed between the Howe Range and Bastion Point. Little of the inner barrier remains, the most visible remnants are the Goodwin Sands. The outer barrier stretches towards Mallacoota Inlet in the west. Barracoota Lake, was formed when the entrance to an arm of the Bottom Lake was blocked by sand. |
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Cape Horn is on a sharp meander of the Genoa River between Gipsy Point and the Top Lake. Here erosion is occurring in Tertiary sands and gravels. Before the sea level rise and the flooding of the valley, Double Creek was a tributary of the Genoa River. The valley of Double Creek was also flooded to form the Double Creek Arm. Double Creek now follows a much shorter course before flowing into the Arm. The Top and Bottom Lakes are separated by a deep and narrow waterway called The Narrows. What was once a river gorge or narrow valley, now has a shoreline washed by estuarine waters. The Goodwin Sands are the remnant of the inner barrier. Saltmarsh, reeds, sand and mudflats sit atop a layer of dune limestone, formed when the barrier was in existence several thousand years ago. |
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Sea grass washed on to a small beach at Cemetery Bight and dried in the sun. Sea grass is an important food source for such fish as the luderick. Saltmarsh is extensive around the shore line of the inlet. Saltmarsh plants are especially adapted to survive in the salty conditions of estuaries. Close to the entrance are the sandflats and mudflats of Devlin's Inlet. These comprise part of the largest tidal delta in Victoria. This stingray has been washed up on to a shoreline of gravels, pebbles and shells, common along The Narrows and at other points around the lake system. |
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There is a considerable amount of mobile sand on the barrier and this is continually being shaped and re-shaped by the wind. The sand here is slowly moving towards Lake Barracoota. Large, mobile dunes are a sulking feature of the exposed Mallacoota Inlet-Cape Howe coastline, as well as the many wrecked ships beneath its stormy waters. |
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Change is continually occurring on the outer barrier. This situation of a dynamic, but durable system is well illustrated by reference to the entrance of Mallacoota Inlet. Top Left is the entrance in 1984,with a strip of coast wattle and other dune vegetation in the background. After a series of floods in 1985, the entrance has been dramatically re-shaped. The sands of the entrance have again been modified by the currents and waves, with new channels being created by 1987. In 1988 the entrance has again been deepened and widened by a flood. |
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Mallacoota can experience large amounts of rainfall in only a few days and the lake can rise rapidly. This flood in Easter l985 resulted after over 200 millimetres of rain fell over two days Passengers of this cruise boat had to wade through water that had covered the wharf, usually a metre above the water level. Later in the same year a higher flood occurred. Roads were also covered by the flood. Seagrass and other debris has been carried well across the road and left there with the ebbing of the waters. Two years earlier, in March 1983, the town of Mallacoota was endangered by bushfires. |
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The boulder-strewn course of the Genoa River, upstream from the small village of Genoa. Although the river appears to have a small waterflow, it can rise quickly after rains and these large granite boulders can easily be lifted and carried by the turbulent floodwaters. Warm temperate rainforest hugs the banks of the Wallagaraugh River. Forest areas have been cleared for agriculture, here on river flats. Clearing began in the catchment with the arrival of white settlers in the 1830s and 1840s. The main reason for forest clearance in the catchment nowadays is woodchipping. |
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These cliffs are carved in sedimentary sand stones, shales and slates laid down in the Ordovician, 450-500 million years ago. The coastline between Mallacoota and Little Rame Head reveals the best exposure of such rocks in Victoria. The picture on the left was taken during high seas at Bastion Point. The two on the right look in the opposite direction and shows more clearly the low profile of the shore platforms. The rounded form of the granite cliff at Sandpatch Point contrasts with that of the Ordovician cliffs at Bastion Point. |
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The layered and tilted nature of the Ordovician sediments has made it difficult for clear-cut zonation patterns to emerge in the inter-tidal zone. Neptune's necklace is seen herein the parallel pools formed along the joints in the rock. A sulking zonation pattern is clearly revealed here on a vertical face of granite. Surf barnacles and mussels. |
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Sunrise at Bastion Point. Rock pools merge at high tide, but tend to be small and scattered at low tide due to the irregular geological structure of the rocks. Cunjevoi, also known as sea squirts, at Sandpatch Point. Abalone in rock pools are a rare occurrence and only found in isolated areas where inaccessibility restricts their collection by people. |
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Tip Beach, is a steeply sloping beach stretching from the Betka River to Bastion Point. Gabo Island used to be joined to the mainland by a narrow deposit of sand, called a tombolo. It became separated at the start of the century. The island has breeding colonies of penguins and mutton birds. The small bay in which Shelly Beach has formed seems to have sufficient rocks to trap and retain large amounts of mollusc shells. The cliffs at Quarry Beach were once used as a source of road gravel. |
Copyright Mallacoota P-12 College
