Mk211 is right, that website is very good to start looking, also I doubt many little cities will have a lot of jobs to do with geology but I'm sure a lot of the big cities like sydney where I'm originally from has many jobs and also places like Melbourne and Brisbane, there the cities I'm more familiar with but I'm not too sure about places like perth or Darwin, I live in the gold coast now, and it's a beautiful place as is sydney and Melbourne, but the gold coast now probably isn't the best for looking for a job, employment is pretty limited here, but places like sydney and Melbourne are very multicultural to so being from spain u Shud fit in no problems, anyway hope this helps 
