Hydrothermal mineral deposit

Hydrothermal mineral deposits are accumulations of valuable minerals which formed from <a href="/facts/Hydrothermal_circulation/hqwwksSm">hot waters circulating</a> in Earth's <a href="/facts/Crust_(geology)/FYG1kP4F">crust</a> through fractures. They eventually produce <a href="/facts/Metal/PT8hNX6R">metallic</a>-rich fluids concentrated in a selected volume of rock, which become <a href="/facts/Supersaturation/YaTN0D1L">supersaturated</a> and then <a href="/facts/Precipitation_(chemistry)/s3BgsLLY">precipitate</a> ore minerals. In some occurrences, minerals can be extracted for a profit by mining. Discovery of mineral deposits consumes considerable time and resources and only about one in every one thousand prospects explored by companies are eventually developed into a mine. A mineral deposit is any geologically significant concentration of an economically useful rock or mineral present in a specified area. The presence of a known but unexploited mineral deposit implies a lack of evidence for profitable extraction.
Hydrothermal mineral deposits are divided into six main subcategories: <a href="/facts/Porphyry_copper_deposit/Bnt30Noj">porphyry</a>, <a href="/facts/Skarn/CAPVrImS">skarn</a>, volcanogenic massive sulfide (VMS), <a href="/facts/Sedimentary_exhalative_deposits/jdQBtAeH">sedimentary exhalative</a> (SEDEX), and epithermal and Mississippi Valley-type (MVT) deposits. Each hydrothermal mineral deposit has different distinct structures, ages, sizes, grades, geological formation, characteristics and, most importantly, value. Their names derive from their formation, geographical location or distinctive features.
Generally, porphyry-type mineral deposits form in hydrothermal fluid circulation systems developed around <a href="/facts/Felsic/0jpm1eSA">felsic</a> to intermediate <a href="/facts/Magma/hRotHju9">magma</a> chambers and/or cooling <a href="/facts/Pluton/y65IUQps">plutons</a>. However, they did not precipitate directly from the magma. While, a skarn deposit is an assemblage of ore and calc-silicate minerals, formed by <a href="/facts/Metasomatic/loQ477Ke">metasomatic</a> replacement of <a href="/facts/Carbonate_rock/pKYTxRkM">carbonate rocks</a> in the <a href="/facts/Contact_aureole/8eWHgy6K">contact aureole</a> of a pluton. Volcanogenic massive sulfide deposits form when mafic magma at depth, (perhaps a few kilometers beneath the surface), acts as a heat source, causing <a href="/facts/Convective/E8vsCPhu">convective</a> circulation of seawater through the <a href="/facts/Oceanic_crust/0lGjI7jN">oceanic crust</a>. The hydrothermal fluid leaches metals as it descends and precipitates minerals as it rises. Sedimentary exhalative deposits, also called sedex deposits, are lead-zinc sulfide deposits formed in intracratonic sedimentary basins by the submarine venting of hydrothermal fluids. These deposits are typically hosted in <a href="/facts/Shale/bsIhqY5F">shale</a>. Hydrothermal epithermal deposits consist of <a href="/facts/Geological_vein/TyETstxF">geological veins</a> or groups of closely spaced geological veins. Finally, Mississippi Valley-type (MVT) are hosted in <a href="/facts/Limestone/8ntvtFnR">limestone</a> or <a href="/facts/Dolomite_(rock)/EGXDL0zm">dolomite</a> that was deposited in a shallow marine environment in a <a href="/facts/Tectonically/jPcFacFP">tectonically</a> stable intraplate environment. As expected in such an environment, <a href="/facts/Volcanic_rock/ID3oPwtM">volcanic rocks</a>, <a href="/facts/Fold_(geology)/WWDL3kjf">folding</a> and regional <a href="/facts/Metamorphism/8eWHgy6K">metamorphism</a> are absent as a general rule. MVT deposits commonly lie in close proximity to <a href="/facts/Evaporites/vNW8fcEy">evaporites</a>.

Hydrothermal mineral deposit open-in-new

Hydrothermal mineral deposit