High demand? Not law.
If you don't mind living in woop woop, mining engineering
edit:
to elaborate on this - resources is one of Australia's largest (if not THE largest) sectors and it's only gonna get bigger because of international interest. The Australian government foreign investment review board found that foreign investment was by far the greatest in resources ($80.9 billion in 2009-10); recent RBA research shows it's going to grow even more in the next 5-10 years. We're probably not going to run out of mining industry jobs for quite a while, and this isn't restricted to mining engineering although I think they'd probably earn more than the people operating the machines or whatever