Chromite stratiform and podiform and pge ore deposits world wide. Ore deposits produced by magmatic segregation, with special. The deposition of ore minerals, predominantly galena and sphalerite, occurred during the hydrothermal phase under a diminishing influence of magmatic co 2. Magmatic ore deposits in layered intrusions descriptive. The geology of ore deposits download ebook pdf, epub, tuebl. Selected bibliographies of hydrothermal and magmatic mineral deposits. 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 ore deposits are products of natural smelting. Magmatic and structural controls on the tonnage and metal. Introduction to ore forming processes download pdfepub. It is assumed that there is relation between geothermal and epithermal ore deposits hedenquist et al. Jan 10, 2017 economic geology magmatic ore deposits 2 1. We then use these data to discuss the evolution of uppercrustal magmatic hydrothermal systems and speculate on how a range of vapor evolution paths might explain the formation of porphyrystyle and epithermal ore deposits. These deposits are mined primarily for their platinum, palladium, and rhodium contents table 1.
Ore deposit geology john ridley mapping closely to how ore deposit geology is now taught, this textbook systematically describes and illustrates the major ore deposit types, linking this to their settings in the crust, and the geological factors behind their formation. Clair state university of iowa follow this and additional works at. 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. Magmatic ore deposits form through processes that are, for the most part, normal aspects of the crystallization of mafic to ultramafic magmas. All except three of the papers that were presented are published in this volume as well as some of the discussion and the summation of the symposium. These crystals may settle onto the bottom of the intrusion, concentrating ore minerals there. Multiple constraints from chospbsr isotopic compositions. The deposit can consist of massive ores in some cases, a nd disseminations of rare minerals in others. 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 sulfides within large maficultramafic intrusions, mined for platinumgroup elements. Students who gain less than 40% in the exam will be considered to have failed the course, irrespective of the semestermodule mark. They eventually create rich metallic fluids concentrated in a selected volume of rock, which become supersaturated and then precipitate ore minerals. Volcanogenic ore deposits magmatic ore formation systems 32.
Discrimination between magmatic and hydrothermal nicu. Large layered igneous complexes are the major repositories of cr, pge. Much less frequently magmatic deposits may occur in the form of flows that issue from volcanic vents for example, volcanic sulfur flows. Most granitic plutons show concentric wall inwards zonation. This monograph on magmatic ore deposits has resulted from a symposium held at stanford university on november 12 and, 1966. Magmatic deposits article about magmatic deposits by the. Mapping magmatic and hydrothermal processes from routine. Chromite stratiform and podiform and pge ore deposits worldwide. This work has been identified with a creative commons public domain mark 1. Tonys students are involved in virtually every aspect of the ni and pge industries. Rocks formed as a result of magmatic segregation are called magmatic cumulates. Exposed plutonic rocks represent the final stage of a longterm evolution punctuated by several magmatic events with different chemistry and generated under different mechanical conditions.
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. Most of the nickel mined in canada comes from magmatic deposits such as those in sudbury ontario, thompson manitoba figure 20. It is evident that nickel, copper, chromium, vanadium. Chromite and magnetite are ore minerals that form in. As early crystallizing minerals form from magma, they incorporate certain elements, some of which are metals. Ore deposits produced by magmatic segregation, with. Ore deposits form by a variety of natural processes that concentrate elements into a volume that can be economically mined. Some of these minerals are extremely rare and almost never encountered in common rocks, an example being alloys of the platinum metals. Models of environments and geometries linking mantle. These deposits are also sometimes called volcanichosted massive sulfide vhms deposits. These deposits vary in shape and occur in igneous rocks that are related to them in origin. The formation of valuable minerals in magma that is cooling is. Magmatic ore deposits are derived from accumulations of crystals of metallic oxides, or. Sulfide ore deposits occupy a spectrum from accumulated.
If you continue browsing the site, you agree to the use of cookies on this website. Magmatic ore deposits commonly occur in the following forms. Usually form from hydrothermal and magmatic processes. We dedicate this collection of papers to professor tony naldrett, whose pioneering efforts laid the groundwork for so much of our current understanding regarding the genesis of magmatic nicupge deposits. This short course has a strong focus on field observations and handson practical skills, supported by an understanding of theoretical aspects. Magmatic fluids and gases with a very high metal transport capability may then form at a late stage and may be released directly into the magmatic hydrothermal or epithermal ore forming system. The principal styles of mineral deposit which have formed by magmatic segregation are listed in. Magmatic sulfide ore deposits elements geoscienceworld.
In recent years, hydrothermal magmatic systems in modern volcanism areas have been in focus of researches as ore generating structures. Magmatic ore deposits in layered intrusionsdescriptive. They eventually create richmetallic fluids concentrated in a selected volume of rock, which become supersaturated and then precipitate ore minerals. Models of environments and geometries linking mantle plumes to magma chambers and high level intrusions are illustrated in figs. Provides an updated guide to the processes involved in the formation of mineral deposits offers an overview of magmatic, hydrothermal and sedimentary ore forming processes covers the entire range of mineral deposit types, including the fossil fuels and supergene ores relates metallogeny to global tectonics by examining the. Many of these are used in making various kinds of steels. Much more uncommon than maficultramafic magmatic ore deposits. Magmatic ore deposits magmatic ore deposits are deposits where the metal is found in the primary magma, and as. Magmatic base metals deposits chrome nickelcopper platinum group metals pgm magmatic deposits are so named because they are genetically linked with the evolution of magmas emplaced into the crust either continental or oceanic and are spatially found within rock types derived from the crystallization of such magmas. A magmatic ore deposit is an accumulation of magmatic minerals. View test prep magmatic ore deposits from geol 6960 at the university of oklahoma.
Ore deposits formed by gravity settling due to magmatic. Sources of ore forming material for pbzn deposits in the sichuanyunnanguizhou triangle area. Role of magmatic activity in the generation of ore deposits mdpi. In some occurrences, minerals can be extracted at a profit by mining. 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. Click download or read online button to get the geology of ore deposits book now. While a magma may start as a homogeneous liquid, magmatic segregation. Complexes segregated via magmatic processes and was subsequently modified by hydrothermal processes. However, ore formation in the interior of modern hydrothermal magmatic systems is. Pdf highly siderophile and strongly chalcophile elements.
Iron ore deposits iron ore deposits are known to occur in sedimentary, hydrothermal, and magmatic environments, but production today is almost entirely from three types of deposit. Insights into the compositional evolution of crustal. Ore deposits in an evolving earth download ebook pdf. Classification of magmatic ore deposits geoscienceworld. 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. Gadjah mada university, yogyakarta, indonesia odes, entre of ore deposit and earth sciences, university of tasmania tmv, ar industrial transformation research hub, university of tasmania. Mineral deposit mineral deposit magmatic cumulates. The evolution of crustal magmatic systems is incompletely understood, as most studies are limited either by their temporal or spatial resolution. Such magmas form through melting in hotterthannormal parts of the mantle, and they rise towards the crust because their density is, on. He has served as mentor to many of the authors of the chapters contained in this book, and his willingness and desire to share his vast knowledge of magmatic ore deposits is a mark of the educator and the gentleman that tony is. Copper deposits 3platinum group metal pgm deposits. Magmatic segregation is an ore forming process, in which the valuable minerals are concentrated by settling them out from cooling magma. Magmatic ore deposits in layered intrusionsdescriptive model for. The mineral system approach applied to magmatic nicupge.
Click download or read online button to get magmatic ore deposits book now. Magmatic ore deposits are derived from accumulations of crystals of metallic oxides. Kong, zhigang wu, yue liang, ting zhang, feng meng, xuyang lu, lin and yang, g. No layering due to 100 higher mew, also due to lower density differences between minerals. For example, if the average grade of a porphyry deposit is 0. Magmatic segregation can also take place as a result of the separation of sulphide and silicate liquids. Magmatic ore deposits download ebook pdf, epub, tuebl, mobi.
Liquation deposits in the strict sense of the word, where the separation of the ore melt is a natural process, taking place dur ing the cooling of the magma, as in the. The host rock for the mineralization can range from ultramafic to felsic. 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 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. Their type, character and abundance reflect the environment in which they formed and thus they preserve key evidence for the evolution of magmatic and tectonic processes, the state of the. Ore deposits produced by magmatic segregation, with special reference to the nickel ores of the sudbury district, ontario stuart st. Magmatic ore deposits chapter 2 ore deposit geology. In addition, abundant, highquality geochemical data provide insights into magmatic and hydrothermal processes that were previously difficult to recognize and that have obvious applications to mineral exploration and improved genetic models of ore deposits. The submarine tectonomagmatic framework of cuau endowment. A single deposit can contain tens of millions tons of cu, millions tons of mo, and thousands tons of au, meaning that pcds have become priority targets for modern mineral. Kodi archive and support file vintage software community software apk msdos cdrom software cdrom software library console living room software sites tucows software library software capsules compilation shareware cdroms cdrom images zx spectrum doom level cd. Primary expressions of ore deposits a well known aspect of ore deposit expression is the association of particular ore types with particular host rock assemblages, i. Through the magmatic segregation process, one or more minerals are concentrated locally during the cooling of magma. Sulphide and silicate liquids are immiscible meaning they do not mix, so droplets of iron, copper, nickel and platinum sulphides that form at high temperatures and are denser than the surrounding silicate liquid magma sink to the base of the intrusion to form a cumulate layer, where they.
The information from these logs is currently processed by slow manual. The rocks that are formed as a result of magmatic segregation are called magmatic cumulates. Magmatic ore deposits in layered intrusionsdescriptive model. Ore deposits that form in and around igneous rock units as a result of mineral precipitation from aqueous solutions or hydrothermal fluids are. In magmatic segregations, economic minerals get concentrated more or less at the place of their formation such as along bottom or margins of an igneous body.
Only students with a semestermodule mark of more than 50% and an exam mark of more than 35% will be. Ores in magmatic arcs indonesia 8 19 march 2019 prefield trip workshop. One of the most critical stages in the development of magmatic hydrothermal ore deposits is the stage at which aqueous fluids are exsolving from the crystallizing melt 1. A number of processes that occur during cooling and crystallization of magmatic bodies can lead to the separation and concentration of minerals. Magmatic ore deposits geoscienceworld books geoscienceworld. An ore deposit formed by magmatic segregation, generally in mafic rocks and layered intrusions, as crystals of metallic oxides or from an immiscible sulfide liquid. Volcanogenic massive sulfide ore deposit wikipedia. Hydrothermal mineral deposits are accumulations of valuable minerals which formed from hot waters circulating in earths crust through fractures. A magmatic deposit is one in which the metal concentration takes place primarily at the same time as the formation and emplacement of the magma. Discrimination between magmatic and hydrothermal nicupge. This site is like a library, use search box in the widget to get ebook that you want. Magmatic ore deposits magmatic ore deposits are those which are formed during crystallization of a magma, deep underground. The relationship of layered igneous intrusions and associated magmatic ore deposits to mantle plumes is discussed in the preceding chapters.
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