Pdf crustal sulfur is required to form magmatic nicu. Major critical commodities found within maficultramafic orthomagmatic mineral systems include pge, chromitite and v and ti oxides. 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. 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. The chemical principle governing precipitation of an immiscible. Role of magmatic sulfides and mafic alkaline magmas in the. Pdf magmatic sulfiderich nickelcopper deposits related. Copper deposits 3platinum group metal pgm deposits. Magmatic sulfide rich nickelcopper deposits related to picrite and or tholeiitic basalt dikesill complexes. Appendix c geologic and geotechnical reports for the eagle. Introduction magmatic sulfide deposits are, with the exception of sudbury, generally considered to be the product of continental rifting naldrett, 2004. Sms deposits were first recognized during the exploration of the deep oceans and the mid ocean ridge spreading. All their host rocks, except the sudbury igneous complex, are thought to be mantle derived melts.
The role of arsenide melts as collectors of platinumgroup. This book is an enormously expanded and updated version of his original textbook on the subject. The common association of pges with sulfide minerals is a result of processes of magmatic and sulfide liquid segregation and fractionation. 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. 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 sulfide liquids. Magmatic sulfide ore deposits request pdf researchgate. Volcanogenic massive sulfide ore deposit wikipedia. On the basis of their principal metal production, magmatic sulfide deposits in mafic rocks can be divided into two major types. Sron garbh is an appinitediorite intrusion emplaced into dalradian metasediments in the tyndrum area of scotland that hosts magmatic cunipgeau sulfide mineralisation in the appinitic portion. Magmatic ore deposits in layered intrusionsdescriptive model.
The pilbara craton has one of the oldest known mineralised layered. The sudbury igneous complex is thought to be the product of complete melting of continental crust. The magmatic model for the formation of magmatic sulfide deposits carries with it concepts that have many implications for exploration some simple, qualitative, and in common use and others. With the notable exception of jinchuan, gansu province, china, the host rocks for class 1 ni sulfide deposits are gabbronorite or troctolite. These deposits are also sometimes called volcanichosted massive sulfide vhms deposits. Most magmatic nicupge sulphide deposits occur within longlived magma pathways fed by high degree partial melts of the mantle. Magmatic sulfide deposits are sulfide mineral concentrations in mafic and ultramafic rocks derived from immiscible sulfide liquids. Some of these minerals are extremely rare and almost never encountered in common rocks, an example being alloys of the platinum metals. Other large komatiitichosted magmatic ni sulfide deposits located in the yilgarn craton include the perseverance, kambalda, yakabindie and honeymoon deposits markwitz et al. Discrimination between magmatic and hydrothermal nicupge. Formation of magmatic nickel sulfide ore deposits and. Exploration for magmatic nicupge sulphide deposits.
Generally found in mafic or ultramafic igneous rocks, typically layered complexes. Gold is probably sequestered to a similar but undetectable extent hattori, 1987. Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows, mined primarily for ni and cu. The appropriate physical environment is required so that the sulfide. The term has been coined by mineral explorers to differentiate the modern deposit from the ancient. Appendix c geologic and geotechnical reports for the eagle project. The host intrusion of the huangshannan deposit is composed of a layered ultramafic sequence.
The central goal for the project has been to develop a new methodology for magmatic sulfide deposit exploration by investigating host rock compositions at a distance of hundreds of meters away from the deposits, outside of down hole geophysical. Magmatic cunipgeau sulfide mineralisation in alkaline. Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b, and 7a. Magmatic cuni sulfide mineralization of the huangshannan. In china, however, convergent plate tectonic settings are almost as important as intraplate environments for magmatic nicu sulfide deposits fig. Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b, and. They form following the segregation of an immiscible sulfide liquid from a maficultramafic magma, with chalcophile elements being concentrated in the sulfide liquid, which accumulate into economic deposits. 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. This probably explains the low magmatic sulfide abundances of slowly cooled, large porphyritic intrusions, and most im. Ripley2 1 mlr key laboratory for the study of focused magmatism and giant ore deposits of magmatic ore deposits, xian institute of geology and mineral resources, xian 710054, china. 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.
Although the size of the deposit is small, containing 0. Applied earth science transactions of the institution of mining and metallurgy b 119, 193204. The model incorporates thermodynamic consideration of the oversaturation of sul. A magmatic ore deposit is an accumulation of magmatic minerals. 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 con tamination. Together, these processes remove greater than 90 percent of the original endowment of magmatic sulfides. Many important metal resources, such as ni cu, co, pge, exist in magmatic sulfide deposits, are a hot spot in geological research. Magmatic sulfide deposits models 1, 2b, 5a, 5b, 6a, 6b. The magmatic sulfides from the bingham and tintic systems sequester critical amounts of orerelated metals. Magmatic deposits deposits in which the ore minerals have crystallized directly from a magma. Ripley, editors additional copies of this publication can be obtained from society of economic geologists, inc.
Nickel deposits explained magmatic nickel sulphide deposits the bulk of nickel mined today comes from either nickel laterite deposits, in deeply weathered terrains where nickel is released from the weathering of ultramafic rocks, or from nickel sulphide deposits which is our primary focus at grasset. Magmatic sulfide rich nickel copper deposits related to picrite and or tholeiitic basalt dike sill complexes uniform series open file report geological survey u. Magmatic sulfide ore deposits are products of natural smelting. Nickelcopper sulfide ore deposits are found at the base of mafic and ultramafic bodies. In the case of mantlederived magmas, a high degree of partial melting of the mantle serves to. Volcanogenic massive sulphide deposits alan galley, mark hannington and ian jonasson geological survey of canada, 601 booth street, ottawa, on, k1a oe8 email. Geochronological, petrological, and geochemical studies of. Crustal sulfur is required to form magmatic nicu sulfide deposits. Magmatic sulfiderich nickelcopper deposits related to. Abstractmagmatic sulfide deposits typically occur in ultramaficmafic systems, however, mineralisation can occur in more intermediate and alkaline magmas.
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. In contrast, sulfide saturation may be delayed in feenriching magmatic series, allowing cu to increase as seen in island arc magmatic suites. Magmatic sulfide deposits fall into two major groups when considered on the basis of the value of their contained metals, one group in. Geochronology, geochemistry and srndpbhf isotopes of.
Classification of magmatic sulphide deposits in china and. Low temperature alteration of magmatic nicupge sulfides as. Fundamentals of magmatic sulfide deposits magmatic nicu and. Layered, ultramafic to mafic intrusions are uncommon in the geologic record, but host magmatic ore deposits containing most of the worlds economic concentrations of platinumgroup elements pge figs. Sulphide magma as a source of metals in arcrelated. A preliminary quantitative model for the formation of magmatic sul. Introduction most worldclass magmatic sulfide deposits are formed within cratons or on their margins in association with intraplate magmatism barnes and lightfoot, 2005. Magmatic sulfide deposits are likely to form by this reductioninduced sulfide saturation mechanism deep within other arcs where magma mixing is thought to be common. Magmatic sulphide deposits provides an updated summary of the state of understanding of the most important ni sulfide deposits. Magmatic sulfide deposits geology, geochemistry and. Request pdf magmatic sulfide ore deposits magmatic sulfide ore deposits are products of natural smelting.
Notes title from pdf title screen usgs, viewed oct. Magmatic sulfiderich nickelcopper deposits related to picrite and or tholeiitic basalt dikesill complexesa preliminary deposit model. The fate of magmatic sulfides during intrusion or eruption. Thus, instead of hosting magmatic sulphide deposits, magmatic arcs are host mainly to magmatic hydrothermal deposits, for example, porphyry and epithermal deposits, which.
Sulfide accumulation beneath an impactgenerated crustal melt sheet. Multiple sulfur and iron isotope composition of magmatic. Sulfidesilicate textures in magmatic nicupge sulfide. Magmatic nicupge sulfide deposits in china request pdf. Because the purpose of this deposit model is to facilitate the assessment for undiscovered, potentially economic magmatic nicupge sulfide deposits in the. Complexes segregated via magmatic processes and was subsequently modified by hydrothermal processes. Much less frequently magmatic deposits may occur in the form of flows that issue from volcanic vents for example, volcanic sulfur flows. Sulfide ore deposits occupy a spectrum from accumulated pools of matte within small igneous intrusions or lava flows. The mineral system approach applied to magmatic nicupge. Geology, genesis, and exploration for magmatic pgecu. Discrimination between magmatic and hydrothermal nicu. Sulfidesilicate textures in magmatic nicupge sulfide ore. A case of magmatic sulfide mineralization in southern europe l. Economic geology principles and practice metals, minerals, coal and hydrocarbons introduction to formation and sustainable exploitation of mineral deposits, walter l.
Posted on october 20, 20 by economicgeo a colleague and i visited a university geology department in the vicinity of a project we were working to do a presentation on the geology of the project. However, there are rare magmatic sulfide occurrences that are dominated by curich sulfides e. Magmatic ore deposits in layered intrusionsdescriptive. Jan 01, 2017 magmatic sulfide deposits typically occur in ultramaficmafic systems, however, mineralisation can occur in more intermediate and alkaline magmas. Magmatic sulfiderich nickelcopper deposits related usgs.
A cooling magma will sometimes precipitate droplets of a second magma that has an entirely different composition. The ionic radius of divalent nickel is close to that of divalent iron and magnesium, allowing the three elements to substitute for one another in the crystal lattices of some silicates and oxides. The huangshannan nicu pge sulfide deposit, a new discovery from geological prospecting in eastern tianshan, is in a belt of magmatic nicu pge sulfide deposits along the southern margin of the central asian orogenic belt. Although available platinumgroupelement pge data from. How to make porphyry copper deposits sciencedirect. These deposits are mined primarily for their platinum, palladium, and rhodium contents table 1. Olivine chemistry and sulfur isotopes of the newly. Traditionally, ore genesis models emphasize crustal incorporation of sulfur as the key process that triggers sulfide liquid immiscibility in a magmatic system lesher and campbell, 1993. The formation of the magmatic sulfide deposits in magma conduit systems, such as the norilsk nicupge deposit, voiseys bay nicuco deposit, and the magmatic sulfide deposits at the bases of komatiite flow, and the pge deposits in large layered intrusions, such as the bushveld intrusion and great dyke, are closely related to mantle. Magmatic sulfide deposits are the worlds most important source of ni and platinumgroup elements pge and significant associated cu. Jan 10, 2017 economic geology magmatic ore deposits 2 1. A three year, camiro research and development project on metal dispersion near magmatic sulfide deposits has been completed.
The most important beds in magmatic deposits are those of iron, titanium, vanadium, chromium, platinum, copper, nickel, cobalt, apatite, diamonds, niobiumtantalum, zirconium, and hafnium. However, some of the mineralization in some deposits e. Such examples include jinchuan on the western margin of the north. Formation of magmatic nickelsulfide ore deposits and. Request pdf origin of noblemetal nuggets in sulfide saturated arc magmas.
Sulfide saturation of a magma is not enough in itself to produce an ore deposit. 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 second in which the pge are the most important. A number of processes that occur during cooling and crystallization of magmatic bodies can lead to the separation and concentration of minerals. Magmatic deposits article about magmatic deposits by the. 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. The role of external sulfur in the genesis of magmatic nicupge sulfide deposits has been widely debated. Origin of noblemetal nuggets in sulfidesaturated arc. Jun 01, 2006 read classification of magmatic sulphide deposits in china and mineralization of small intrusions, acta geologica sinica english edition on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. A different kind of magmatic segregation involves liquid immiscibility. Magmatic sulfide ore deposits elements geoscienceworld. Apr 22, 2012 typical magmatic sulfides are dominated by pyrrhotite and pentlandite with minor chalcopyrite, and the bulk atomic cufe ratio of these sulfides is typically less than unity.
How potassium silicate alteration suggests the formation of porphyry ore deposits begins with the nearly explosive but barren expulsion of large volumes of magmatic water. 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 sulfide. Sulfide solubility increases with feo content, thus fedepleting magmatic series should deplete in cu, consistent with the low cu contents of continental arc magmas lee et al. A number of factors such as initial pge and as content of sulfide melt, arsenide sulfide melt ratio, efficient concentration of aspge bearing mineralsmelt and timing. Magmatic nicu sulfide ore deposit in the eastern kunlunorogenic belt, qinghaitibet plateau zhang zhaowei1, li chusi2, wang yalei 1, li wenyuan1 and edward m. Moreover, the concen tration of ni in rocks consisting of 100 percent sulfides ranges from 1 to 6 percent. The copper content of a magma is strongly partitioned into a magmatic sulfide phase when it is present candela, 1989.