The Rosebery mine uses a mechanised underground mining method called open stoping to extract ore from up to 1.5 kilometres below the surface.
The underground mine consist of tunnels, called declines or ramps, that provide access from the surface to areas below.
Illustration of underground mining at Rosebery
Connected to these ramps are horizontal drives or levels from which to access the ore body.
Underground drill rigs called development jumbos are used to drill horizontal holes into the rock face. These holes are usually up to 3.5 metres in length and once drilled are charged with explosives and blasted to loosen the rock. The blasted rock is then removed by a loader. To ensure the walls and ceiling of these tunnels are stable, the development jumbos install a mixture of rock bolts and mesh, cable bolts and shotcrete to provide safe access. This cycle of drilling, blasting, excavating and stabilising is repeated to develop the tunnels.
Development jumbo at Rosebery
Production drill rigs then drill 30-40 metre long holes from one level to another which are loaded with explosives and blasted. The blasted ore is removed by loaders, leaving an empty space called a stope.
Loader at Rosebery
The ore is then loaded into 50-tonne trucks which haul the ore out of the mine to where it is crushed and processed. The trucks at Rosebery travel approximately 60,000 kilometres each year – roughly equivalent to circumnavigating the earth one and a half times each year.
The stopes are then filled with waste rock to prevent cave-ins.
For information on how the ore is processed please visit the Rosebery Processing page.