G'Day there The Beans
That question would literally take years to answer. It is almost worth considering where gold is NOT found. There are some particular rock types that are unlikely or rarely contain gold or gold deposits of economic size (and what is economic also changes with time and technology). For example a rock type like the Sydney sandstone has not produced any gold depoisits and much of the flat lying Cretaceous cover shales covering large parts of central and eastern Australia also have no known gold occurrences. You are unlikely to find gold in oil bearing sands and clays or undeformed or un-metamorphosed limestones and so on. Everthing else is generally up for grabs. new deposits are now being found in areas and rock types previously thought not worth searching in Australia and around the world. One particular story can serve to demonstrate. A few decades ago a geologist was travelling along a highway in Canada going to a new job. he needed to stop for a call of nature rather fast as a result of the previous night's celebrations - as it were. He rushed up a bank in a cutting to seek some privacy, let loose and in doing so washed off sand and soil from a particular rock face - he recongnised a gold bearing alteration system - this "discovery" resulted in the the huge Hemlo field.
In Australia I worked with a bloke who found Olympic Dam. He told the drillers to not drill below a certain interval while he was away - they were looking for a particular rock boundary. He also told the drillers to not stop drilling until he got back, thinking he had plenty of time. He however was convinced to stay another night in town by his girlfriend and when he got back the drillers had gone through the boundary unexpectedly early, staight into the top of the ore body. The result - one of the largest mines in world history in a rock type not only never thought to contain gold but never before seen.
Araluen
