
Composition, Formation, and Occurrence of Polymetallic Nodules
... In addition to the abovementioned abyssal manganese nodules of the large oceans mentioned above, there are many other locations in the world’s oceans that host special Mn-(Fe)-nodules. The formation and composition of such nodules are controlled by local conditions such as hydrothermal (seafloor mas ...
... In addition to the abovementioned abyssal manganese nodules of the large oceans mentioned above, there are many other locations in the world’s oceans that host special Mn-(Fe)-nodules. The formation and composition of such nodules are controlled by local conditions such as hydrothermal (seafloor mas ...
an example to sepiolite formation in volcanic belts by
... township of Bolu Province, northcentral Turkey, have been investigated in detail, and new mineralogical data have been obtained. Differing from the sedimentary sepiolite deposits, mostly associated with the carbonate/evaporite sequences, Kıbrıscık sepiolite occurs in the Köroğlu (Gallatian) Volcanic ...
... township of Bolu Province, northcentral Turkey, have been investigated in detail, and new mineralogical data have been obtained. Differing from the sedimentary sepiolite deposits, mostly associated with the carbonate/evaporite sequences, Kıbrıscık sepiolite occurs in the Köroğlu (Gallatian) Volcanic ...
volcanogenic massive sulphide deposits
... also known as volcanic-associated, volcanic-hosted, and volcano-sedimentary-hosted massive sulphide deposits. They typically occur as lenses of polymetallic massive sulphide that form at or near the seafloor in submarine volcanic environments. They form from metal-enriched fluids associated with sea ...
... also known as volcanic-associated, volcanic-hosted, and volcano-sedimentary-hosted massive sulphide deposits. They typically occur as lenses of polymetallic massive sulphide that form at or near the seafloor in submarine volcanic environments. They form from metal-enriched fluids associated with sea ...
Magmatic Ore Deposits
... grade. Abundant carbonate alteration (dolomite and ankerite). Silver-rich and anomalous gold zones containing ruby silver or electrum. Black ore (in graphitic schist); white ore (in massive barite, quartz and carbonate). ...
... grade. Abundant carbonate alteration (dolomite and ankerite). Silver-rich and anomalous gold zones containing ruby silver or electrum. Black ore (in graphitic schist); white ore (in massive barite, quartz and carbonate). ...
Guide to Epithermal Gold and Silver in NL
... other metals and may in fact be the source of these metals in various types of epithermal deposits. Epithermal gold mineralization typically forms close to volcanic and geothermal hot spring activity, such as hot springs or geysers (Figure 3): these are the surface expression of hydrothermal syste ...
... other metals and may in fact be the source of these metals in various types of epithermal deposits. Epithermal gold mineralization typically forms close to volcanic and geothermal hot spring activity, such as hot springs or geysers (Figure 3): these are the surface expression of hydrothermal syste ...
Volcanogenic Massive Sulfide Deposits
... amounts of felsic and mafic volcanic rocks, the geodynamic setting is an important first-order control on the compositions of the deposits; some classification schemes have attempted to link the bulk compositions of VMS to their geodynamic environments. For example, the Cu-rich deposits found in oph ...
... amounts of felsic and mafic volcanic rocks, the geodynamic setting is an important first-order control on the compositions of the deposits; some classification schemes have attempted to link the bulk compositions of VMS to their geodynamic environments. For example, the Cu-rich deposits found in oph ...
Ore deposits related to intermediate to felsic intrusions – Formation
... Such assemblage can be of the same chemical composition as the original rock, when the alteration is isochemical, or be of a new chemical composition when the alteration is allochemical In both cases the new mineral assemblage reflects the i) original rock composition, ii) the properties and the amo ...
... Such assemblage can be of the same chemical composition as the original rock, when the alteration is isochemical, or be of a new chemical composition when the alteration is allochemical In both cases the new mineral assemblage reflects the i) original rock composition, ii) the properties and the amo ...
Nature and origin of Lofdal Carbonatite associated REE Deposit
... Since China, the greatest rare earth elements (REE) producer, has decided to stockpile its resources therefore creating artificial shortage in the world, intensive exploration for REE, comprising La-Lu+Y, Sc (Lottermoser, 1992), has increased. Lofdal intrusive complex, located in northwestern Namibi ...
... Since China, the greatest rare earth elements (REE) producer, has decided to stockpile its resources therefore creating artificial shortage in the world, intensive exploration for REE, comprising La-Lu+Y, Sc (Lottermoser, 1992), has increased. Lofdal intrusive complex, located in northwestern Namibi ...
From Source to Sinks in Auriferous Magmatic
... Porphyry-type systems are spatially and genetically associated with porphyritic intrusions. The stocks are of calcalkaline to alkaline composition and oxidized. The stocks are characterized by hydrous phenocryst phases, such as amphibole and biotite, whose stability requires at least 4 wt% H 2O in ...
... Porphyry-type systems are spatially and genetically associated with porphyritic intrusions. The stocks are of calcalkaline to alkaline composition and oxidized. The stocks are characterized by hydrous phenocryst phases, such as amphibole and biotite, whose stability requires at least 4 wt% H 2O in ...
From Source to Sinks in Auriferous Magmatic
... Porphyry-type systems are spatially and genetically associated with porphyritic intrusions. The stocks are of calcalkaline to alkaline composition and oxidized. The stocks are characterized by hydrous phenocryst phases, such as amphibole and biotite, whose stability requires at least 4 wt% H 2O in ...
... Porphyry-type systems are spatially and genetically associated with porphyritic intrusions. The stocks are of calcalkaline to alkaline composition and oxidized. The stocks are characterized by hydrous phenocryst phases, such as amphibole and biotite, whose stability requires at least 4 wt% H 2O in ...
the basic mineralogic, paragenetic and genetic
... The author's field observations and ore-microscopic examinations of numerous sulphide deposits located in the region have shown that the volcanic-sedimentary type of deposits are more developed here, although these deposits are characterized, as a rule, by the presence of later hydrothermal sulphide ...
... The author's field observations and ore-microscopic examinations of numerous sulphide deposits located in the region have shown that the volcanic-sedimentary type of deposits are more developed here, although these deposits are characterized, as a rule, by the presence of later hydrothermal sulphide ...
Volcano Menu
... • Volcanic Hazards of Quiet Eruptions – Quiet Eruptions: • Lava flows- set fire and bury everything in ...
... • Volcanic Hazards of Quiet Eruptions – Quiet Eruptions: • Lava flows- set fire and bury everything in ...
Host rock composition and hydrothermal alteration as tools for
... this contact the MV-Qtz developed from Au, As, Ag, Sb, Bi and W-enriched fluids. Although the Nalunaq deposit is orogenic, the close spatial association with calcalkaline and porphyritic granites is intriguing. Elements such as Sb, Bi and W are often associated with felsic igneous rocks and also ind ...
... this contact the MV-Qtz developed from Au, As, Ag, Sb, Bi and W-enriched fluids. Although the Nalunaq deposit is orogenic, the close spatial association with calcalkaline and porphyritic granites is intriguing. Elements such as Sb, Bi and W are often associated with felsic igneous rocks and also ind ...
Hydrothermal vent Activities At the Gjallar Ridge In the
... synthetized were identified by Apps and van de Kamp (1993) as follows: (1) Degassing and / or cooling of mafic magma at spreading centres. The most abundant gases are carbon dioxide and hydrogen sulphide, the presence of methane is also notable. These gases are amongst the fluids emitted by hydrothe ...
... synthetized were identified by Apps and van de Kamp (1993) as follows: (1) Degassing and / or cooling of mafic magma at spreading centres. The most abundant gases are carbon dioxide and hydrogen sulphide, the presence of methane is also notable. These gases are amongst the fluids emitted by hydrothe ...
232186_232186
... There is a further point of significance to the elevated F in the Olympic Dam hydrothermal system. The hydrothermal breccia that hosts Olympic Dam contains abundant angular and splinter-shaped clasts that are readily explained by conventional hydrothermal fragmentation processes such as brittle frac ...
... There is a further point of significance to the elevated F in the Olympic Dam hydrothermal system. The hydrothermal breccia that hosts Olympic Dam contains abundant angular and splinter-shaped clasts that are readily explained by conventional hydrothermal fragmentation processes such as brittle frac ...
Document
... suiTounded by Precambrian gneiss (Fig. 2). Although a direct contact between magmatic rocks and the mineralisation has not been found the mineralisation is considered as a product of the Tertiary magmatic activity. The volcanic rocks in the area are mostly quartz latite and andesite with K/Ar ages b ...
... suiTounded by Precambrian gneiss (Fig. 2). Although a direct contact between magmatic rocks and the mineralisation has not been found the mineralisation is considered as a product of the Tertiary magmatic activity. The volcanic rocks in the area are mostly quartz latite and andesite with K/Ar ages b ...
Regional alteration systems associated with Snow Lake VMS
... syngenetic alteration that occurs as discordant, and broad, semi-conformable zones that are often associated with sulphide mineralization. Several major hydrothermal events occurred within the primitive and mature volcanic arc succession of the Snow Lake area: (1) Semi-concordant and discordant amph ...
... syngenetic alteration that occurs as discordant, and broad, semi-conformable zones that are often associated with sulphide mineralization. Several major hydrothermal events occurred within the primitive and mature volcanic arc succession of the Snow Lake area: (1) Semi-concordant and discordant amph ...
Epithermal antimony, mercury, and gold deposits in the continental
... CO2, SO2, H2S, and HCl from the magma reach the geothermal water reservoir as ascending gas phases where an equilibrium between altered rocks, gas components, and fluids are performed. The ascending fluids contain CO2, H2S, and HCl particularly. The sulfur isotope of ore minerals suggest that the su ...
... CO2, SO2, H2S, and HCl from the magma reach the geothermal water reservoir as ascending gas phases where an equilibrium between altered rocks, gas components, and fluids are performed. The ascending fluids contain CO2, H2S, and HCl particularly. The sulfur isotope of ore minerals suggest that the su ...
Niches of the pre-photosynthetic biosphere and geologic
... deplete hydrogen to values of ∼13 nM. Air at habitable temperature in equilibrium with this water contains ∼20 ppm by volume of H2. ...
... deplete hydrogen to values of ∼13 nM. Air at habitable temperature in equilibrium with this water contains ∼20 ppm by volume of H2. ...
Chapter 29: Formation of Rocks
... Volcanoes also form when an oceanic plate slides under another oceanic plate. ...
... Volcanoes also form when an oceanic plate slides under another oceanic plate. ...
Investigating a Mid-Ocean Ridge Hydrothermal System on Land: the
... Steam turbines in geothermal plants generate electricity by condensing the steam separated from the two phase system which, depending upon the enthalpy and pressure at which steam separation occurs, is often only 20-30% of the total mass flow. The concept behind the Iceland Deep Drilling Program is ...
... Steam turbines in geothermal plants generate electricity by condensing the steam separated from the two phase system which, depending upon the enthalpy and pressure at which steam separation occurs, is often only 20-30% of the total mass flow. The concept behind the Iceland Deep Drilling Program is ...
How Minerals Form
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
How Minerals Form
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
How Minerals Form - Mrs. Pickering`s Accelerated Science
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
How Minerals Form - Mr. Stewart's Science Classes
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
... Slow cooling leads to the formation of minerals with large crystals. If the crystals remain undisturbed while cooling deep below the surface, they grow according to a ...
Hydrothermal vent

A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Hydrothermal vents exist because the earth is both geologically active and has large amounts of water on its surface and within its crust. Common land types include hot springs, fumaroles and geysers. Under the sea, hydrothermal vents may form features called black smokers. Relative to the majority of the deep sea, the areas around submarine hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fluids. Chemosynthetic bacteria and archaea form the base of the food chain, supporting diverse organisms, including giant tube worms, clams, limpets and shrimp. Active hydrothermal vents are believed to exist on Jupiter's moon Europa, and Saturn's moon Enceladus, and ancient hydrothermal vents have been speculated to exist on Mars.