Sorry, I missed the part where you said you had completed your undergrad work, meaning you already have a degree? In what? In the States you can pursue a higher and lower degrees simultaneously, the lower degree being analogous to a 'minor'. I'm not familiar with Australia's higher education system, and don't know how much math and physics you have under your belt, but the question for me would be how many of the credits accumulated along the way could apply and overlap, making a shorter run at two degrees, or one Masters degree with an unusual skill set.
I am an active member of the AGU and the GSA, and have made presentations at annual meetings. But it's not my field, per se. All of my work is self-funded, as an avocation, with no real commercial interests on my part. I just never lost interest (love, really) in geology and geophysics, generally speaking. It's still a frontier, and quite exciting to me. The first four years of my adult working life were spent in mineral and oil exploration fields, but only as an electrical engineer/technical side, from resistivity and magnetometer survey equipment for mineral exploration, to "wireline logging" equipment in the oil field ("tools" with radioactive sources lowered into an open or cased hole at a drilling site). However, I have been self-employed most of my adult life, with most of my time spent serving the semiconductor industry.
I told my son years ago never to look at any field generically, or with a "masses" mindset, except to generally quantify it -- before actually taking a good, hard look. Your job isn't to simply "find a high paying job in a field", but rather to
carve out and explore your favorite niche within that field; something that excites you, fits your favorite mode of thinking, working and living, where you can excel in your chosen specialty to the point where your "competition" becomes nothing more than a handful of welcome and relatively few colleagues. And that can be in any field.
A geologist out in the sun doing field work; surveying, coring, or taking samples with a rock pick comes to the mind of most who think about geology, and while that happens it is most definitely not the whole picture. Geology was once used as the label that encompasses all the hard geosciences, but it's evolved into kind of a misnomer now, with distinctions between geology and geophysics blurred to the casual observer. Geology is more focused on the empirical and qualitative, studying the composition and history of rock on all scales, while geophysics tends to focus more on quantitative, mathematically driven physics-based models that are more qualitative, less empirical. However, both geology and geophysics have myriad branches, many of which dovetail and crossover, and many of which have virtually no emphasis on field work. It's so specialized in so many cases that the number of opportunities are practically limitless for anyone who actually goes in and studies both fields.
I don't where in Oz you are, but Oceana's IGC is having a giant meeting in a couple of months. If you have the opportunity to attend, and you can get to Brisbane, I think you would find it an enormous eye-opener -- and pay closest attention to the vendors there, as that could also be the source of niche market for you.
http://www.34igc.org/
That's just one - but you can make a lot of friends there, and get invaluable input from a lot of people. Listen especially to the grumblers - the whiners and complainers (most of whom are trapped in academia, dependent on publishing, playing politics, and seeking out the next "funding opportunity"). Then look at the obviously happy ones, and specifically why it is they're happy. There are many, many good opportunities for high paid work with normal family life in all the geosciences. Whatever you do, don't go in without a road map. Quantify it - find your favorite opportunity and specifically
target it.
