Sydney Map and information
This map shows the Sydney area, from Botany Bay in the south to Long Reef in the north, and out to Parramatta.
Geological background
Sydney is a sandstone place. The Hawkesbury sandstone is about 200 metres thick, and almost the whole of Sydney is made from this rock. There are shale caps on a few ridges, and a few small lenses of shale in the sandstone, but for the most part, the soils are poor and barren, carrying a huge range of diverse plants, specialised in living on this poor soil. Every small variation opens up a niche for yet another group of plants, and they flower the year around. They have to, in order to take full advantage of the available resources. This explains why Banks was captivated by what he saw, with plants blooming at the start of the southern winter.The sandstone is jointed: mainly north-south, and east-west. During the last Ice Age, the sea levels fell all around Australia, but we had little glaciation. The rivers cut down into the sandstone, producing deep trenches on a fern leaf pattern. Later, when the sea levels rose again, we were left with the modern shape of Sydney Harbour. All that you see coloured blue here is tidal and navigable.
The cliffs of the headlands around the harbour also depend on the jointing -- as a cliff is undercut by wave action, so huge blocks of stone peel off and tumble into the sea, where the waves grind them down into sand once more, freeing the sand grains for the first time in 200 million years.
(Click here for more about the sandstone of Sydney.)
The beaches
Almost every inlet, every concavity, offers a beach, a sandy shore with easy access to the water. The steep sides of the harbour were once cliffs, allowing ships to anchor in several fathoms of water, within spitting distance of the shore. The tidal range is between one metre and two metres, and the bays are protected from howling winds by hills nearby. It was ideal for a maritime settlement -- it was a pity about the soil, though.You see, the sand wasn't just on the beaches, it was on the shore as well. Which is why people had to head off up to Parramatta, right over on the left-hand side of the map. There were patches of shale soil out there, where decent crops could be grown, but for the first 25 years, Sydney needed food that was imported from Norfolk Island, plus food brought from further afield.
The cliffs
Still to come
Try the links to
Botany Bayand
Long Reef
This file is http://www.ozemail.com.au/~macinnis/sydmap.htm
It was last revised on March 18, 1997
It was created by Peter Macinnis -- macinnis@ozemail.com.au
Unless otherwise indicated, all materials shown here are free of any copyright restrictions.