The Laterite Capping

Our Rocky Foundation - The End of the Geosyncline - The Long Slow Decline - The Laterite Capping
Creating our present landscape - The Sandy Border - Mining in the Yankalilla District - Geology Map

The Laterite Capping

Widespread in the high areas of the Mt Lofty Ranges is a layer of red ironstone called laterite, It is well-developed in the southern Fleurieu and on Kangaroo Island, where it is often used as a road metal, sometimes to the detriment of unwary drivers. Its age is hard to determine, but it is probably Triassic, roughly 200 million years old, and 100 million after the Permian ice age. Laterite is formed by weathering in iron-rich soils, and so it represents the remains of an ancient land surface, a landscape which had been eroded to one of low relief, sometimes called a peneplain ('almost a plain'}. Much of our high country still has an undulating feel, with shallow valleys between low hills all of a similar height.

Widespread laterite formation, remnants of an ancient land surface, now often spotted in road cuttings

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