| Archaean cratons are amongst the more mineralized provinces on Earth. The formation of large ore deposits involves large-scale fluid flow through the crust. The fluids leach the rocks and transport metals. Fluids are channelled along permeable path-way concentrating further the metals in relatively small volume of rocks.
In archaean craton foliation triple junction may have channelled large volume of fluids. This is supported by some numerical experiments that investigates their thermal history. The diagram on the right shows the evolution of temperature through time at two locations: the centre of the granites, and the centre of the triple junction.
At first the triple junction act as a sink for heat (heat flows from hotter to colder region) but rapidly becomes a source of heat as its temperature rises above that of the granites. As fluids flow down temperature foliation triple junction acts as huge pump sucking fluids when it is colder that the granite, releasing fluids when it becomes hotter.
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