Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily for ni and cu, to stratiform layers of weakly. Magmatic and metallogenic framework of aucu porphyry and polymetallic carbonatehosted replacement deposits of the kassandra mining district, northern greece chris r. Northmet and dunka, and how they relate to the twin metals deposits. Magmatic sulfide deposits in the emeishan large igneous province, sw china, have variable chalcophile and siderophile metal contents and can be divided into pge, nicupge and nicu deposits. Kambalda type komatiitic nickel ore deposits are a class of magmatic ironnickelcopperplatinumgroup element ore deposit in which the physical processes of komatiite volcanology serve to deposit, concentrate and enrich a fenicupge sulfide melt within the lava flow environment of an erupting komatiite volcano. Formation of magmatic nickelsulfide ore deposits and. Magmatic sulfide deposits are sulfide mineral concentrations in mafic and ultramafic. Magmatic sulfide ore deposits are products of natural smelting. The absolute concentrations of pge in sulfides from different deposits vary over a range of five orders of magnitude, whereas those of other chalcophile elements vary by factors of only 2 to 100.
The distribution coefficients between sulfides and silicates d sulsil range. Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily. The magmatic sulfides from the bingham and tintic systems sequester critical amounts of orerelated metals. Magmatic ore deposits in layered intrusionsdescriptive. Controls on the metal compositions of magmatic sulfide. Magmatic sulfide deposits geology, geochemistry and exploration naldrett, anthony j. To model these processes, we carried out analog experiments in which dense silicone oil droplets were transported in a viscous aqueous polymer solution. Os isotopic geochronometer and tracer to four komatiite. The copper content of a magma is strongly partitioned into a magmatic sulfide phase when it is present candela, 1989. The composition of magmatic ni cu pge sulfide deposits. Sulfide saturation of a magma is not enough in itself to produce an ore deposit. Magmatic sulfide deposits containing nickel ni and copper cu, with or without platinumgroup elements pge, account for approximately 60 percent of the worlds nickel production. Holistic mineralsystem analysis for such deposits has some parallels with dominantly hydrothermal systems, but also some important differences.
Exploration for platinum deposits magmatic sulfide deposits fall into two major groups when considered on the basis of the value of their contained metals, one group in which ni, and, to a lesser extent, cu, are the most valuable products and a. A synthesis of magmatic nicupge sulfide deposits in. Although the importance of magma conduits for the formation of. Pge deposits are believed to have formed by segregation of immiscible sulfide melts andor alloys from maficultramafic magmas in dynamic magmatic systems such as lava channels, feeder dikes, and magma chambers. Most ni sulfide ore deposits occur as a cluster of deposits known as a mining camp.
Magmatic sulfide deposits fall into two major groups when considered on the basis of the value of their contained metals, one group in. It will be noticed that the authors ascribe the formation of these magmatic sulphide deposits to causes very different from those generally accepted. The appropriate physical environment is required so that the sulfide liquid mixes with. The majority of magmatic nicupge sulfide deposits are hosted within sulfidebearing country rocks e. Formation of magmatic nickel sulfide ore deposits and processses affecting their copper and platinumgroup element contents. The formation of valuable minerals in magma that is cooling is. Magmatic deposits deposits of minerals formed deep in the earths crust during the solidification and crystallization of basic or alkaline magma containing high concentrations of valuable minerals. Oct 20, 20 magmatic sulphide deposits are of course important from an exploration and mining perspective because they host economic quantities of copper, nickel, and the platinum group elements pge. Assimilation of sulfur with sedimentary signature3. Analog experimental insights into the formation of magmatic. Magmatic segregation is a general term referring to any process by which one or more minerals become locally concentrated segregated during the cooling and crystallization of a magma. Role of magmatic sulfides and mafic alkaline magmas in the.
Petrological and geochemical observations from the ovoid ore. There are many factors which govern their size and grade, and the development of different exploration tools based on the interplay between these factors. Volcanogenic massive sulfide ore deposits, also known as vms ore deposits, are a type of metal sulfide ore deposit, mainly copperzinc which are associated with and created by volcanicassociated hydrothermal events in submarine environments. These deposits vary in shape and occur in igneous rocks that are related to them in origin. Some of these minerals are extremely rare and almost never encountered in common rocks, an example being alloys of the platinum metals. The pilbara craton has one of the oldest known mineralised layered intrusions in the world hoatson, 1998. Sulfidesilicate textures in magmatic nicupge sulfide ore deposits. Magmatic deposits article about magmatic deposits by the.
The first group of deposits, hosted by the phoenix, selkirk and tekwane intrusions occurs within and in the periphery of the tati greenstone belt fig. Regardless of the size of the sulfides, the properties remain similar. Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily for ni and cu. All the common oreforming elements are present in magmas and ordinary rocks, in amounts ranging from a few parts per billion to several thousands of parts per. Summary all of the major chinese magmatic sulfide deposits appear to be associated with major thermal events. The composition of magmatic ni cu pge sulfide deposits in. Discrimination between magmatic and hydrothermal nicu. Geology, genesis, and exploration for magmatic pgecuni. Holistic mineralsystem analysis for such deposits has some parallels with dominantly hydrothermal systems, but also some. Due to the extremely high partition coefficient between sulfide and.
Rocks formed as a result of magmatic segregation are called magmatic cumulates. Magmatic and metallogenic framework of aucu porphyry. On the basis of their principal metal production, magmatic sulfide deposits in mafic rocks can be divided into two major types. A cooling magma will sometimes precipitate droplets of a second magma that has an entirely different composition. Pge sulfide deposits include the jinbaoshan and zhubu deposits and have ores with very low sulfide contents 1 to 2 vol. Magmatic sulfide deposits are divisible into two major groups, those that are valued primarily for their ni and cu and that are mostly sulfide rich 10% sulfide, and those that are valued primarily for their pge and tend to be sulfide poor pdf. Together, these processes remove greater than 90 percent of the original endowment of magmatic sulfides. Platinumgroup elements pge are mined predominantly from deposits that have formed by the segregation of molten ironnickelcopper sulfides from silicate magmas. Much less frequently magmatic deposits may occur in the form of flows that issue from volcanic vents for example, volcanic sulfur flows. These deposits are mined primarily for their platinum, palladium, and rhodium contents table 1. Magmatic cunipge sulfide deposits often show evidence for the importance of crustal contamination processes in their genesis. In the case of mantlederived magmas, a high degree of partial melting of the mantle serves to. Klein summary of relevant geologic, geoenvironmental, and geophysical information deposit geology magmatic sulfide deposits are sulfide mineral concentrations in mafic and ultramafic rocks derived from. Variably metamorphosed middle precambrian sedimentary and volcanic rocks, including the mesabi and cuyuna iron ranges, with known reserves of iron and manganese.
Gold is probably sequestered to a similar but undetectable extent hattori, 1987. Magmatic sulfide ore deposits request pdf researchgate. The eastern botswana nicupge deposits may be subdivided into two groups. Magmatic sulfide deposits geology, geochemistry and exploration. The sizes of these sulfides vary greatly, from massive magmatic sulfide ore deposits to micrometersized blebs trapped in a silicate crystal. Pdf the mineral system approach applied to magmatic ni. This probably explains the lowmagmatic sulfide abundances of slowly cooled, large porphyritic intrusions, and most importantly, allows metals and sulfur to participate in the formation of porphyry deposits. Sulfidesilicate textures in magmatic nicupge sulfide ore. Volcanogenic massive sulfide ore deposits, also known as vms ore deposits, are a type of metal sulfide ore deposit, mainly copperzinc which are associated with and created by volcanicassociated hydrothermal events in submarine environments these deposits are also sometimes called volcanichosted massive sulfide vhms deposits.
Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b. Magmatic ore deposits are derived from accumulations of crystals of metallic oxides, or immiscible sulfide, or oxide liquids that formed during the cooling and crystallization of magma, typically with mafic to ultramafic compositions. Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b, and 7a. The fate of magmatic sulfides during intrusion or eruption. Magmatic sulfide deposits containing nickel ni and copper cu, with or without. Klein summary of relevant geologic, geoenvironmental, and geophysical information deposit geology magmatic sulfide deposits are sulfide mineral concentrations in mafic and ultramafic rocks derived from immiscible. The reos isotopic system has proven to be a very useful tracer of contamination in these types of deposits. However, some of the mineralization in some deposits e. The deposits were discovered in 1963 by sedge botswana ltd. Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily for ni and cu, to stratiform layers of weakly disseminated. Exploration for magmatic nicupge sulphide deposits. These deposits are mainly distributed in the danba, panzhihuaxichang panxi, huili, yuanmou, midu, funing and jinping regions in sw china and the ta khoa region. Request pdf magmatic sulfide ore deposits magmatic sulfide ore deposits are products of natural smelting.
Vms volcanogenic massive sulphide deposits and nicuco type magmatic massive sulphide deposits volcanicassociated massive sulphide vms deposits occur throughout the world and throughout the geological time column in virtually every tectonic domain that has submarine volcanic rocks as an important constituent. Nickelcopper sulfide ore deposits are found at the base of mafic and ultramafic bodies. Volcanogenic massive sulfide ore deposit wikipedia. Oxides oxidizing environments form hydroxyoxide minerals, very insoluble metal concentrations especially fe, mn, al hydrothermal ore deposits thermal gradients induce convection of water leaching, redox rxns, and cooling create economic mineralization massive sulfide deposits hot, briny, water leaches metals from basaltic ocean. Magmatic sulfide deposits geology, geochemistry and. Other ores nisulfide deposits, sedimenthosted uranium deposits, kupferschiefer copper deposits cannot yet be readily assigned to specific plate tectonic regimes or processes. All their host rocks, except the sudbury igneous complex, are thought to be mantle derived melts. A number of processes that occur during cooling and crystallization of magmatic bodies can lead to the separation and concentration of minerals. Magmatic fenicu platinumgroup element pge sulfide deposits form when mantlederived mafic and ultramafic magmas become saturated in sulfide and segregate immiscible sulfide liquid, commonly following interaction with crustal rocks. Other large komatiitichosted magmatic ni sulfide deposits located in the yilgarn craton include the perseverance, kambalda, yakabindie and honeymoon deposits markwitz et al. Secular variation of magmatic sulfide deposits and their. A magmatic ore deposit is an accumulation of magmatic minerals. Each individual ore deposit generally contains greater than 10,000 t ni.
Formation of magmatic nickel sulfide ore deposits and. In the united states, exploration for cobalt deposits may focus on magmatic nickelcopper deposits in the archean and. Magmatic sulphide deposits provides an updated summary of the state of understanding of the most important ni sulfide deposits. The mineral system approach applied to magmatic nicupge. Copper deposits 3platinum group metal pgm deposits. This book is an enormously expanded and updated version of his original textbook on the subject. During this process, cold seawater penetrates through cracks. Fundamentals of magmatic sulfide deposits magmatic nicu and. A different kind of magmatic segregation involves liquid immiscibility.
Geology, genesis, and exploration for magmatic pgecuni deposits c. Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b, and. A third classification that is gaining popularity in canada is. These include lowsulfide, contacttype, and reeftype pge deposits, chromite deposits, and fetiv deposits. Indicator minerals for magmatic sulfide mineralisation. Article the composition of magmatic nicupge sulfide deposits in the tati and selebiphikwe belts of eastern botswana w. Magmatic sulfide minerals concentrated in ultramafic volcanic rocks. Origin and metal content of magmatic sulfides in cuau. Magmatic nicupge sulfide deposits can occur with a number of other magmatic ore deposits. Most magmatic nicupge sulphide deposits occur within longlived magma pathways fed by high degree partial melts of the mantle. The metal content of the sulphides is governed by the concentration of the metals in the silicate host magma, the. An overview of deposit types, accompanied by a summary of. Most major magmatic cunipge sulphide deposits are thought to have formed by segregation of an immiscible sulphide melt from a silicate host magma, in response to processes such as magma mixing, rapid cooling, differentiation, and contamination. Schedule geol 5606 exploration for magmatic ore deposits.
Genesis of magmatic sulfide deposits curtis d williams. Tectonic settings of magmatic sulfide deposits in china. Classification of mafic and ultramafic rocks and related magamatic sulfide deposits 3. Sulfur sources and magmatic sulfide mineralization in the. Magmatic fenicu platinumgroup element pge sulfide deposits form when mantle.
Magmatic sulfiderich nickelcopper deposits related to. This probably explains the low magmatic sulfide abundances of slowly cooled, large porphyritic intrusions, and most im. Geology, genesis, and exploration for magmatic pgecu. Magmatic sulfide ore deposits elements geoscienceworld. This probably explains the low magmatic sulfide abundances of slowly cooled, large porphyritic intrusions, and most importantly, allows metals and sulfur to participate in the formation of porphyry deposits. Multiple sulfur and iron isotope composition of magmatic ni. Magmatic nicu sulfide deposits form as the result of segregation and concentration of droplets of liquid sulfide from mafic or ultramafic magma, and the partitioning of chalcophile elements into these from the silicate melt. Pdf on nov 1, 2012, xieyan song and others published magmatic nicu and pge deposits. Thompson, tim baker,2 richard friedman,3 pavlos tsitsanis,4 sally russell, 4 scott randall, and jim mortensen3. Many intrusionhosted nicu magmatic sulfide deposits, such as voiseys bay labrador, canada and jinchuan china, show evidence for latestage mobilization of highdensity, lowviscosity sulfiderich melts, which range from sulfiderich silicate magma pulses to coherent pulses of pure sulfide liquid. The chemical principle governing precipitation of an immiscible. General description of the duluth complex magmatic pge deposits.
Overall, magmatic sulfide deposits is strongly recommended to. Curich magmatic nicupge deposits top magmatic deposit producers 20072008 simexmin 2014 symposium may 14, 2014 deposit location operators cu pa tonnes cu grade norilsk taimyr peninsula, russia norisk nickel 364,400 2. Most of the remainder of the ni production is derived from lateritic deposits, which form by weathering of ultramafic rocks in humid tropical conditions. In addition, secondary processes can produce associated asbestos, soapstone, and native copper deposits. The sudbury igneous complex is thought to be the product of complete melting of continental crust. Hydrothermal deposits associated with ultramafic rocks, typified by the bouazzerdistrict of morocco, represent another type of primary cobalt deposit. Abstract magmatic nicupge sulfide deposits in the ca. Jan 10, 2017 other ores ni sulfide deposits, sedimenthosted uranium deposits, kupferschiefer copper deposits cannot yet be readily assigned to specific plate tectonic regimes or processes.
Cobaltstyles of deposits and the search for primary deposits. The most important beds in magmatic deposits are those of iron, titanium, vanadium, chromium, platinum, copper, nickel, cobalt, apatite, diamonds, niobiumtantalum, zirconium, and hafnium. Magmatic nicu sulfide deposits form as the result of the segregation and concentration of droplets of liquid sulfide from mafic or ultramafic magma and the partitioning of chalcophile elements. Twentyone samples of five different mineralization styles were selected from the ovoid ore body covering the range in mineralogy and textures disseminated sulfide, breccia sulfide, matrix sulfide and massive sulfides ferich and curich. Magmatic sulfide deposits result from transport and settling of dense sulfide liquid droplets in basic magma.
The gaojiachun and lengshuiji nicupge sulfide deposits are hosted by layered mafic intrusions possibly representing part of the neoproterozoic arc along the western margin of the yangtze block fig. The origin of most major sulfide nicu deposits is attributed to the segregation of immiscible sulfide liquids from intraplate silicate melts, in response to assimilation of siliceous or sulfurbearing rocks. The duluth complex consists of 12 mafic subintrusions emplaced into the older rocks during continental rifting over a 10 to 12 millionyear period about 1. Kambalda type komatiitic nickel ore deposits wikipedia. Mineral deposit mineral deposit magmatic cumulates. Magmatic sulfide deposits form via sulfide segregation from mantlederived maficultramafic magmas naldrett, 2004. Discrimination between magmatic and hydrothermal nicupge. When there is a silicate melt present, the sulfide, which is either a. Magmatic sulfiderich nickelcopper deposits related usgs.
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