FIFO- Fly in Fly out. Probably like Canada most of the mines are remote from the cities so the workers will fly in for say 2 weeks then fly out back to a capital city for two weeks. Contracts vary but that would be one type.
The mines are like most companies looking for the cheapest option and the very old Fokkers are much cheaper compared to a 737. Most strips now for the bigger mines are pretty good for being in the middle of nowhere and are bitumen and satellites make things easier.
My rough guide. There are probably people here who do it for a living so will have better info.