How do geological processes contribute to the formation of gold deposits and magmatic fluids?
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Geological processes play a crucial role in the formation of gold deposits and magmatic fluids. Magmatic gold deposits are formed through the involvement of magma, but the exact processes are still debated . Epithermal deposits, which are important sources of gold, are formed through the precipitation of ore minerals from hydrothermal fluids associated with magmatic activities . Metamorphic processes can also contribute to the formation of gold deposits by producing auriferous fluids through devolatilization reactions and subsequent deposition of gold . Orogenic gold systems, on the other hand, are flow-controlled thermodynamic systems that occur in mid- to upper crustal environments, where deformation, fluid flow, heat transfer, and chemical reactions are coupled . Metamorphic fluids, which can vary in composition depending on the original sedimentary environment, have been suggested as a potential source for various ore deposits, including gold deposits .
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98 Citations | The paper discusses the formation of gold deposits and mentions that while there is evidence for gold-quartz vein systems forming through purely metamorphic processes, other processes like late-orogenic magmatism also contribute to gold mineralization. The paper suggests that major deposits like Sunrise Dam may have a more complex origin involving both magmatic and metamorphic processes. However, the specific contribution of geological processes to the formation of magmatic fluids is not discussed in detail in the paper. |
| The provided paper does not directly address the formation of gold deposits and magmatic fluids. It focuses on the fluid pressure build-up below the seismic lid and the fault-valve mechanism for lode-type gold deposits. | |
| The paper explains that metamorphic processes, specifically devolatilisation of basaltic rocks and clastic metasedimentary rocks, produce auriferous fluids that carry gold. These fluids migrate and deposit gold primarily through reduction and wallrock sulfidation. | |
| The paper discusses how trans-crustal geological processes, such as oxidized source mantle, differentiation of ore-forming magmas, and structural focusing of ore-forming fluids, contribute to the formation of giant epithermal gold deposits. However, it does not specifically mention the formation of magmatic fluids. | |
| The paper discusses the controversial nature of the magmatic origin of gold deposits and the need for further investigation into magmatic processes to explain the formation of gold deposits and magmatic fluids. |
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