Sublime Point Lookout

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Looking south from Sublime Lookout toward Wollongong
Looking south from Sublime Lookout toward Wollongong
This is the spectacular view from Sublime Point looking south toward Wollongong.

The escarpment to the right rises 400 metres above the Pacific Ocean to a plateau. The steep vertical cliffs at the top of the escarpment are in Hawkesbury Sandstone, a well-cemented sheet of sand some 100 metres thick that covers the area around Sydney. The Hawkesbury Sandstone stretches for hundreds of kilometres and is easily recognized in the cliffs of the escarpment, along the coast near Sydney and in deep road cuts on the freeway north to Newcastle. This sandstone sheet, as well as the sediments beneath it, was deposited during the global Flood as the floodwaters were rising, some 4,500 years ago.

The events of Noah’s Flood easily explain the distinctive shape of the escarpment. As you look across the landscape, imagine the waters of the Flood covering the landscape to a depth of a kilometre or more. The ocean floor to the left begins to sink relative to the continent on the right. The water begins to run off the continent toward the east in wide sheets eroding the landscape flat and leaving a plateau. The sheet of water forms a long north-south waterfall as it runs into the ocean, technically a hydraulic jump. This carves the escarpment along the coast and carries the sediment far out to sea.

As the water drains away and the flow reduces, it changes from sheet flow to channel flow. Torrents of floodwater now flow in wide channels, carving the long valleys that extend back into the plateau. These extend out into the ocean. Eventually the floodwater is gone. The rivers that flow through the valleys today are tiny compared with the torrent of water that carved them.

When the ocean settled to its present level (after the Flood and after the post-Flood Ice Age) the wide valleys filled with sand, forming a scalloped coastline between rocky headlands.

When you know what to look for it is easy to see the erosive signature of Noah’s Flood in the landscape.