Lec 5 - Nature Of Ore-Bearing Fluids Flashcards
Ore bearing fluids
- magma/magmatic fluids
* hydrothermal fluids
High temp rock melt of liquid and crystals, it produces igneous rocks
Magma
Mafic portions of magma
Cr, Ni, Pt, P
Silic portions
Sn, Th, Zr
Oxide or sulfide dominated magma that solidify directly as ore
Ore magma
Partly crystallized magma is subjected to stress, the fluid fraction is squeezed off from the residual crystalline mush
Filter pressing
Coexistence between 2 liquids and their separation from each other
Liquid immiscibility
Aqueous, high temp fluid solution (100 - 800 C)
Hydrothermal Fluid
At critical temp (367 C) water will not boil but will steadily become less dense
Supercritical Fluid
Sources of Hydrothermal Fluids
- Connate water
- metamorphic Water
- magmatic water
- meteoric water
- sea water
Fluids and volatiles that travel upward from magma
Magmatic/Juvenile Waters
Decrease viscosity of magmas, lower freezing points of minerals, make possible devt of minerals that would form in a dry melt
Fluxes