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and host enclaves of vein stockworks, hydrothermal quartz-pyrite-epidote
breccias and small pods of massive sulphide consisting of mostly pyrite and
traces of chalcopyrite.
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It is likely that similar styles of mineralization and other styles not
yet considered could be exposed on the seafloor in the Macquarie Ridge
Complex which remains under explored due to its remote location and
challenging sea conditions. The Hjort Trench, south of Macquarie Island is
noteworthy for being the deepest point in Australia, around 6700 m below
sea level.
6. Off Shore Extensions to Mineralized Land Terranes
Clues for off shore prospectivity and mineralization can also be gained
from examination of the distribution of mineralization on Australia's land
mass. For example, the Australian land mass hosts around 40,000 mineral
occurrences in rocks ranging in age from Achaean to Mesozoic. Figure 2
shows occurrences of base metal (excluding nickel) and a number of the
major base metal operating mines which are significant contributors to
Australia's GDP. This pattern and distribution of mineral occurrences evi-
dent in Fig. 2 essentially outlines the major exposed geological terranes in
Australia. Based on magnetics and gravity data a number of these terranes
extend into the offshore environment.
Fig. 2. Location of base metal mines and base metal occurrences (excluding nickel) in
Australia.
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