Mineral Resouces of the Adelaide Geosyncline

Description

The Flinders and Mount Lofty Ranges of South Australia consist of rocks once deposited as sediments in an elongated basin. This basin known as the Adelaide Geosyncline, stretches from Kangaroo Island to at least as far as Oodnadatta and across to Broken Hill. The rocks of this world-famous geological province provide a record of changing environments and life forms spanning a period from 1100 to 500 million years before present.

The work of South Australia’s widely travelled pioneer geologists revealed that the eastern highland region of the State, encompassing the Mount Lofty and Flinders Ranges and Olary area, contains a thick and varied accumulation of sediments which were considered to be entirely of Palaeozoic age. The first Government Geologist, H.Y.L. Brown, delineated the extent of outcrop of the Adelaide Geosyncline. Later, Professor Waiter Howchin established the stratigraphic succession in the Mount Lofty Ranges near Adelaide and recognised the glacial origin of the Sturt Tillite.

Professor Sir Douglas Mawson applied the experience of his Antarctic exploration to interpretation of the widespread glacial deposits of the Flinders Ranges and measured sections which became the foundation for all subsequent investigations.

Today, the Flinders and Mount Lofty Ranges are recognised as a classic area for late Proterozoic and Cambrian stratigraphy. Points of special interest include the Ediacara assemblage of metazoan fossils, evidence for late Proterozoic glaciations, unusual carbonate-depositing environments, intrusive carbonate breccias, fossil submarine canyons, and well preserved stromatolites and stromatolite-building micro- organisms.

The Adelaide Geosyncline hosts many former copper mines, of which Kapunda and Burra have been the most important, and numerous small deposits of gold, silver, lead and zinc. Deposits at Oraparinna are Australia’s most important source