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From time to time GSAV is given short presentations about some aspect or other of Victorian geology. Here we have given links to them. Contact the authors directly for more advice or information about the topics.
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| If you are a geologist who would like to add a presentation, field guide, or other material of use to lay people or other geologists, please contact the webweaver. |
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Why is Melbourne where it is?
As very old members will remember Kenneth Williams saying, "I think the answer lies in the soil". See how to read the clues that are left. |
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Victorian Wine Regions and their geology.
Bernie Joyce talks about "terroir", and the explicit influences from the underlying geology that can be observed on wine, winegrowing, and wine appreciation. |
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Apostolic Succession
The collapse of one of the iconic "Twelve Apostles" rockstacks in winter, 2005, was an event remarked around the world. Read some background - and predictions, about the Shipwreck Coast and its geology. |
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Victoria's Volcanoes
There are hundreds of volcanic vents in Victoria - some seen to erupt by families living in the region, thousands of years ago. Some questions about these landforms are answered on a CD-ROM put together by Ken Grimes. Look here, on the Kanawinka Geopark site, for more information. |
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Murray Basin Evolution (PDF file - 20 Mb)
A recent paper by Bowler, Kotsonis, and Lawrence:
BOWLER, J.M., KOTSONIS, A. & LAWRENCE, C.R., 2006. Environmental evolution of the Mallee region,
Western Murray Basin. Proceedings of the Royal Society of Victoria 118 (2): 161-210. ISSN 0035-
9211.
Abstract
The Mallee region preserves legacies of past environmental changes, an understanding of which illuminates
our understanding of the present and constrains some options for the future. An amazing record of
sea level changes spanning the last 6 million years provides a template against which later developments of
lacustrine and aeolian changes are defined in spatial and temporal contexts. The preserved shorelines of
Plio-Pleistocene Parilla Sand provide a virtual contour map of Plio-Pleistocene landscapes clearly displaying
effects of later tectonics. Development of acidic lateritic soil profiles of the Karoonda Surface progressed
synchronously with tectonic interruption of drainage to form the large freshwater lake, Lake
Bungunnia about 3.5 million years ago. Lake Bungunnia cut a southern overflow channel to the sea excavating
the Douglas Depression until uplift on the Padthaway Ridge reached near 60 m AHD. Overflow
ceased, the lake temporarily became a closed system with development of alkaline facies in the west, the
Bungunnia Limestone. Climates throughout this time remained wet and relatively warmer than today. A
later outlet in the south-west drained the lake about 5-700,000 years ago. Major environmental changes are
recorded in the transition from low energy, siliceous Parilla Sand to high energy Bridgewater calcarenites
near 1.3 ma (millions of years). Pliocene 20-40 ka (thousands of years) cyclic sea level oscillations were
followed by 100 ka full glacial cycles near 1 million years ago. Later expansions of aridity in dune fields
and associated calcretes are superimposed on a previously humid controlled landscape. High discharge
Murray River incision on the dry lake floor preserves a pattern of high amplitude variability (big wet to big
dry) far exceeding anything in younger sequences. Dune fields of the Big Desert, Sunset and Little Desert
expanded to the east. Wet and dry events of the last glacial cycle (last 120,000 years) preceded maximum
aridity of the glacial maximum near 20 ka. The arrival of people near 60-50 ka introduced an entirely new
agent of change into the already fragile Mallee landscapes. The scene was set for the much later arrival of
Europeans, the impact of which is now superimposed on 6 million years of natural environmental change.
The lessons from one are essential to a better understanding of the other. |
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