Part 7 of an 11 part series introducing ore deposit geology to nontechnical people. Sedimentary exhalative deposits sedex deposits are ore deposits which are interpreted to have been formed by release of orebearing hydrothermal fluids into a water reservoir usually the ocean, resulting in the precipitation of stratiform ore. Ore bodies structure is generally difficult to observe and its relationships to the regional structural framework is often lacking. Sedex deposits account for more than 50 percent of the worlds zinc zn and lead. Mcqueen crc leme, australian national university, canberra, act 0200 and school of rehs, university of canberra, act 2601. Some of the workers files contained original documentation. Sulphur isotopic data from pyrite and chalcopyrite indicate a biogenic and magmatic origin, at least for part of the cuban sulphides. Mssissippi valleytype mvt and sedimentaryexhalative sedex zinclead deposits represent about half to threequarters of the worlds production and reserves of lead and zinc. Base metal deposits in western cuba belong to the sedex type, as defined by carne and cathro 1982.
Sedimentaryexhalative sedex type deposits syngenetic stratiform, bedded znpb deposits hosted by finegrained clastic sedimentary rocks. Although the specifics of this deposit type are complex goodfellow et al. Guidance for registering on sedex and linking to kingfisher. The spatial distribution and most significant geological attributes of the worlds largest sedimentary exhalative sedex leadzinc metallic mineral deposits and mineral districts are depicted in this data set. This one covers volcanogenic massive sulfide vms and sedimentary exhalative. This report draws on previous syntheses and basic research studies of sedimentary exhalative sedex deposits to arrive at the defining criteria, both descriptive and genetic, for sedextype deposits. Notable examples of this class include the deposits of the bathurst camp, new brunswick, canada e. You remember that nature concentrates the metals by a process of partially melting crustal rocks at depth, letting the metal rise through the crust and cool, dumping the valueless material such as feldspar and amphibole on the way and concentrating the really useful. There is no constrained reinforced or involuntary jail work and people are free to leave their manager after sensible notice. Sedex, or sedimentary exhalative deposits, are ore deposits formed when hydrothermal fluids enter a water reservoir, such as an ocean, and precipitate minerals. Sedimentary exhalative sedex znpbsulfide mineralization first occurred on a large scale during the late paleoproterozoic. The irishtype deposits are stratabound, structurally controlled, carbonatehosted, pbzn deposits that have sedimentary exhalative sedex andor mvt characteristics. In others, alteration is less extensive and or carbonaterich large, 1981. Structural control on the formation of pbzn deposits.
Laborers reserve the option to shape or join workers guilds at their own. To form sedex deposits, you require the deep sedimentary basins so distribution is more limited than that of vms deposits, however they are still found on all continents and there are about 125 sedex deposits on note, and these are marked in red on the map. Minerals free fulltext structural control on the formation of pb. If the site is already registered on sedex, it is very. Sedex deposits represent the result of paleohydrothermal fluid flow similar to modern sedimentary brines circulation in largescale hydrothermal systems.
There is a subclass of vms deposits, the volcanic and sedimenthosted massive sulfide vshms deposits, that do share characteristics that are hybrid between the vms and sedex deposits. Sedex, the supplier ethical data exchange, is a notforprofit organisation based in london, uk, open for membership to any company anywhere in the world. The central irish ore field may be considered as the type setting of carbonatehosted sedex deposits. Proterozoic sedimentary exhalative sedex deposits 171 sulfate. 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. World distribution of sedimentary exhalative sedex pbzn deposits abstract the spatial distribution and most significant geological attributes of the worlds largest sedimentary exhalative sedex leadzinc metallic mineral deposits and mineral districts are depicted in this data set. As sedex deposits comprise over 50% of the worlds zn and pb reserves. Linking sedex and kurokotype massive sulfides explanatory notes a slide presentation and explanatory notes version 1, november 2007. A nmge of orefortl1ing processes in a vmiety of geologic and tectonic environments created these.
Metal sulfi des in most proterozoic deposits have yielded broad. These deposits are hosted by marine sedimentary rocks. The sample payroll direct deposit forms has space for the user to add the name, email address, social security number, signature and other information of the employee. Distribution of contained lead and zinc metal in known sedex deposits through time. You can register as a buyersuppliers ab members or a supplier b members, depending on your requirements. Pdf proterozoic sedimentary exhalative sedex deposits. Geology of basemetal deposits encyclopedia of life. Studies of the tectonic, sedimentary, and fluid evolution of modern and ancient sedimentary basins have also been used to select defining criteria. Sedex deposits encompass over 50 percent of global pb and zn reserves goodfellow et al. Sedex audits sedex, the supplier ethical data exchange, is a notforprofit organisation based in london, uk, open for membership to any company anywhere in the world. Pdf proterozoic sedimentary exhalative sedex deposits and. Sangster df 2002 the role of dense brines in the formation of ventdistal sedimentaryexhalative sedex leadzinc deposits. World distribution of sedimentary exhalative sedex pbzn deposits. Scribd is the worlds largest social reading and publishing site.
Sedimentary exhalative deposits sedex deposits are ore deposits which are interpreted to. Whether your supply chain includes 100s or s of suppliers, sedex advance scales to meet your needs. Instead, sedex deposits are products of high pressure and temperature events that cause dewatering and metamorphism of thick piles of accumulated sediments in intracratonic and epicratonic basins leach et al. Sedimentary exhalative deposits abbreviated as sedex from sedimentary exhalative are ore deposits which are interpreted to have been formed by release of orebearing hydrothermal fluids into a water reservoir usually the ocean, resulting in the precipitation of stratiform ore.
In the pyrenean axial zone paz, the main pbzn mineralizations are commonly considered as ordovician sedex deposits. To achieve sedex deposits, the basin needs to accumulate several kilometres or tens. Sedex deposits are generally formed in faultbounded sedimentary basins on continental crust withinplate locations rather than in volcanic piles on oceanic crust. Pbzn deposits and specifically sedimentaryexhalative sedex deposits are frequently found in deformed andor metamorphosed geological terranes. Sedimentary exhalative deposits sedex deposits are ore deposits that are interpreted to have been formed by release of orebearing hydrothermal fluids into a water reservoir usually the ocean, resulting in the precipitation of stratiform ore gu et al. Copper ore from the sedimentary exhalative deposit at rammelsberg, germany. They are grouped together in the santa luciamatahambre metallogenic district fig.
A hypothesized brine reflux flow system responsible for transporting ore fluids is also shown. The host rocks of the deposits are gritstones, sandstones and black shales, with no igneous rocks involved. Sedex deposits are well known for the large amounts of sulfur they contain, which is present in proterozoic examples almost exclusively as pyrite, base metal sul. These three types may be considered as a spectrum of basemetal ore deposits which form in sedimentary rocks at some time during the evolution of a sedimentary basin. Evidence for lateral fluid flow in ventdistal sedex znpb. This report draws on previous syntheses and basic research studies of sedimentary exhalative sedex deposits to arrive at the defining criteria, both descriptive and genetic, for sedex type deposits. Jan 10, 2017 sedex deposits are generally formed in faultbounded sedimentary basins on continental crust withinplate locations rather than in volcanic piles on oceanic crust. Sedex sedimentary exhalative deposits are one of several types of sedimenthosted leadzinc deposits. Heavy isotopic signatures are often ascribed to fractionation within closed or partly closed local. Sedimentary exhalative sedex zincleadsilver deposit model by poul emsbo, robert r. Sedimentary exhalative sedex deposits account for more than 50 percent of the worlds zinc zn and lead pb reserves tikkanen, 1986 and furnish more than 25 percent of the worlds current production of these two metals and a significant amount of silver ag goodfellow and lydon, 2007.
Testing the potential role of brine reflux in the formation. Sedex deposits are the most important source of lead, zinc and barite, a major contributor of. Proterozoic sedimentary exhalative sedex deposits and. Linking sedex and kurokotype massive sulfides explanatory notes a slide presentation and explanatory notes version 1, november 2007 by andreas g.
Sedimentary exhalative sedex ore deposits are the worlds largest znpb. However, recent work in nevada has demonstrated that the host rocks of midtertiary carlintype gold deposits also contain devonian sedex mineralization, which is significant because these deposits will be mined for gold and not znpb or barite emsbo et al. The current trend toward recovery of lead is certain. Proterozoic sedimentary exhalative sedex deposits 171 sulfate sul. The vast majority of sedex lead and zinc deposits are proterozoic in age, although there are significant jurassic examples in canada and alaska. Sedimentary exhalative sedex deposits are sulfidedominated pbzn ore bodies with sphalerite and galena as the principal ore minerals. Download sedex deposits we are a sharing community.
Introduction ore deposits are crustal concentrations of useful elements that can be exploited at a pro. Sedex deposits are the most important source of lead, zinc and barite, a major. A new genetic model for sedimentary exhalative ore deposits sedimentaryexhalative sedex deposits are one of the most important types of metal ore deposits. The two deposittypes have traditionally been regarded as separate entities in terms of genesis largely because they possess very different morphologies, resulting from the epigenetic nature of mvt deposits and the. Rich accumulations of lead, zinc and silver are found in the ore minerals sphalerite zinc sulfide and galena lead sulfide deposited between thin layers of marine sand, silt and mud in sedimentary basins. If the parent company name of the site has a different name from either the site or the supplier please state the name here. Yyyycczaaxxxxxxxx sedex members ethical trade audit report version 6. Large 1983 describes more subtle types of alteration near some deposits, including increased.
A new genetic model for sedimentary exhalative ore deposits sedimentaryexhalative sedex deposits are one of the most important types of. In some deposits, silicification is the dominant or only alteration meggen, germany and red dog, alaska. Syngenetic stratiform, bedded znpb deposits hosted by. The rammelsberg shalehosted cuznpb sulfide and barite deposit, germany. May 02, 2014 sedex sedimentary exhalative deposits are one of several types of sedimenthosted leadzinc deposits. These payments occur until the 3rd day of the next month. Necessities of sedex audits depend on eti standards and include. So it supports you at each stage of your supply chain programme now and in the future. Gold in sedex deposits gold in 2000 geoscienceworld books. Sedimentary exhalative sedex zincleadsilver deposit model.
Sedex deposits 1 sedex deposits sedimentary exhalative 2 sedex ore 3 znpb reserves and production by deposit type 4 grade and tonnage of all sedex deposits 5 grade and tonnage of some sedex deposits 6 sedex deposits of the selwyn basin 7 tom sedex deposit, yukon 15. Metal sulfides in most proterozoic deposits have yielded broad ranges of predominantly positive. Sedimentary exhalative sedex usgs publications warehouse. Companies join sedex in order to use the sedex webbased system, participate in sedex governance. World distribution of sedimentary exhalative sedex. Shah purpose the objective of this report is to develop a model for sedex deposits based on processes critical to their formation. Sedimenthosted pbzn deposits contain the worlds greatest lead and zinc resources and dominate world production of these metals. The framework for the model development is a mineral systems. Evidence for, and implications of,a genetic relationship. The worldclass howards pass sedex znpb district, selwyn. Proterozoic sedimentary exhalative sedex deposits and links.
Formation of a stratiform znpbag sedex deposit numerical. H istorically, gold has been considered unimportant in sedimentary exhalative sedex znpb and barite deposits. Essential geologic, chemical, physical, and mass balance constraints on sedex ore formation that must be accounted for in any. The rammelsberg shalehosted cuznpb sulfide and barite. Volcanogenic massive sulfide ore deposit wikipedia. Employment is freely chosen click here to return to nctable eti 1. Sedex deposits are closely associated with underlying hyrdrothermal feeder zone hydrothermal alteration not well documented or mapped extends for hundreds of meters into the pre and postore sedimentary sequence and up to several kilometers laterally from the deposit. They are a chverse group of ore deposits hosted by a wide variety of carbonate and siliciclastic roch that have no obviolls genetic association with igneous activity. Ppt sedex deposits powerpoint presentation free to. What are the differences between sedex and vms deposits and how the vms and sedex deposits fit into the overall scheme of things.
It is constantly evolving in line with the latest risks and our members feedback. Pbzn sedex deposits and their copper stockwork roots. Additionally, there is also space for the user to add the bank details of the transferee. Sedex is a membership organisation for businesses committed to continuous improvement of the ethical performance of their supply chains. The mvt sedex relationship save that a continuum does appear to exist between the two major deposittypes. Gold in sedex deposits gold in 2000 geoscienceworld. This is a fictitious report designed to show a good. To achieve sedex deposits, the basin needs to accumulate several kilometres or tens of kilometres of oxygen lacking sediment, usually shales. Sedex paper 2016 the relationship of sedex deposits to.
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