Vms deposits associated with environments dominated by mafic volcanic rocks, but with up to 25% felsic volcanic rocks, the latter often hosting the deposits. Here we use major and trace elements, highresolution sr, nd and pb isotope analyses, experimental petrology and thermodynamic modelling to investigate bimodal magmatism at the iconic carlingford igneous centre, ireland. Some of those vms deposit are considered supergiant deposits, with more than 250 mton of. Some bimodal mafic and mafictype vms deposits are also enriched in precious metals, but.
Some bimodal mafic and mafictype vms deposits are also enriched in precious metals, but many felsicbimodal deposits also show significant au and ag enrichment. Pdf classification of volcanicassociated massive sulfide. Montagne dor is a bimodal mafic aurich vms of northern paramaca greenstone belt. They typically occur as lenses of polymetallic massive sulphide that form at or near the seafloor in submarine volcanic envi ronments. Volcanogenic massive sulphide vms deposits are also known as. The origin of bimodal mafic felsic rock suites is a fundamental question in volcanology.
Licenciate thesis hydrothermal mobilisation of au and. Volcanogenic massive cuznpb sulfide vms deposits occur primarily in subaqueous riftrelated environments e. Bimodal magmatism produced by progressively inhibited. Igneous geochemistry petrochemistry of mafic and felsic rocks associated with vms deposits is extremely useful in delineating potentially fertile ground for vms mineralization. Volcanogenic massive sulfide vms deposits are important global sources of base and precious metals. The drilling programs performed on the ore zones showed that. The three vmsdeposit types are compared to previous vmsclassification schemes in. 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. Society of america, 2002 annual meeting, abstracts with programs 34. This translates to 4,429 tonnes of gold content in the felsic deposits, 3,646 tonnes in the bimodal mafic deposits, and 481 tonnes in the mafic deposits, thus demonstrating the importance of gold in the three vms subtypes. Intraoceanic volcanic arcs and related backarc rifts bimodalmafic.
Vms deposits associated with environments dominated by mafic volcanic rocks, but with up to 25% felsic volcanic rocks, the latter often. Hamama znpbcu vms deposits are hosted along the contact of bimodal metavolcanic. Pdf there are a lot of volcanogenic massive sulfide vms deposits and. Volcanogenic massive sulphide vms deposits are also known as volcanicassociated, volcanichosted, and vol canosedimentaryhosted massive sulphide deposits. In fact, the hamama deposit is hosted in bimodal mafic sequence, but. Morb are associated with vms deposits in backarc ophiolites, and modern midocean ridges and backarc basins figs. Volcanogenic massive sulfide deposits of the world. Mineralization is often associated with the felsic strata. These groups correlate with different submarine tectonic settings, from the most primitive vms environments, represented by ophiolite settings, through oceanic rifted arc. An overview of the use of petrochemistry in regional.
Yubileynoye, sultanovskoye, yamankasy, molodezhnoye, uzelga4, valentorskoye and bimodal felsic kuroko or baymak type. The high heat flow and extensional setting extant during the initial stages of arc development were essential components for forming a vms hydrothermal system. These rocks are composed of dacites and basalts with calcalkaline composition, and reflect the features of the arc volcanism tokel 1977. Ore mineralogy of bimodalmafic vms deposits hosted in. Volcanogenic massive sulfide deposits of the worlddatabase. These vms deposits include what were formerly classified as kuroko, cyprus, and. All three deposits are classified as bimodal mafic volcanichosted massive sulphide vms type. In the ibp, there are some of the most important vms deposits worldwide. The kidd creek is classified as the bimodal mafic vms type because of the following characteristics. Vms deposits associated with siliciclastic sedimentary rock dominated settings with abundant felsic rocks and less than 10% mafic material. Chapter 11 the giant kidd creek volcanicassociated. The irf conforms to the bimodalmafic vms lithotectonic assemblage of.
Volcanogenic massive sulfide ore deposit wikipedia. Mcilvenna bay is part of the bimodalmafic subclass of vms deposits. Bimodal maficdominated vmshosting calderas include the archean noranda and the. Usually, on a good surface prospect or geophysical target, a program of. There is a very good database from previous research on these vms deposits, and this has influenced wider models for the genesis of such deposits. Cumulative frequency of copper grades of bimodalmafic volcanic massive. Genesis and evolution of the hamama volcanic massive sulphide. The vms model dmec decennial mineral exploration conference. This nomenclature considers not only the huge volumes of reserves but also its high grades in copper, tin, zinc and other nonferrous metals. Volcanogenic massive sulfide deposits lakehead university. The volcanic sequence is cut by the richards lake synvolcanic pluton and the chisel mafic intrusion.
The lithological units range from mafic to felsic compositions, which is consistent with bimodal volcanism. A coeval activity of two submarine volcanic centers at a water depth. Primitive bimodal mafic volcanicdominated oceanic rifted arc and bimodal felsicdominated siliciclastic continental backarc terranes contain some of the worlds most economically important vms districts. Volcanogenic massive sulfide ore deposit wikimili, the. Goldrich volcanogenic massive sulphide deposits au vms are a subtype of both volcanogenic massive sulphide vms and lode gold deposits poulsen and. The noranda, flin flonsnow lake and kidd creek camps would be classic districts of this group. The setting, style, and role of magmatism in the formation. Volcanic and intrusive rocks hosting the mineralization yielded upb zircon ages of 2152to2 ma and a crosscutting porphyry intrusion constrains the minimum age of the vms at 2117. In this paper, 867 deposits were used to construct revised grade and tonnage models. It is important to classify vms deposits based on these types, allowing for comparison between similar deposits based on tectonic. Vms deposits proexmin prospecting exploration minerals. Examples include the noranda, flin flonsnow lake and kidd creek camps canada. 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. World map showing the distribution of volcanogenic massive sulfide deposit subtypes 26 tables 1.
Ghalerigi and siahmadan bimodalmafictype deposits in the sssz. The montagne dor deposit is a bimodalmafic type vms deposit hosted by a southfacing highlystrained volcanic sequence of the paramaca greenstone belt. Golden share announces the acquisition of sandridge project. The subsequent phase 2 9991 ma volcanic sequence comprises more evolved mafic rocks and similar, but more depleted, felsic rocks erupted in a relatively shallow marine setting.
Deeprock minerals commences drilling on the ralleau vms. Deposits are classified based on host rock compositions. Most znenriched deposits are hosted in phanerozoic sequences, but there are a numerous of znrich, zinciferous, and znanomalous deposits in archean and. Throughout earths history, all volcanogenic massive sulfide vms hosting environments are associated with specific assemblages of mafic and felsic rocks with distinct petrochemistry petrochemical assemblages indicative of formation at anomalously high temperatures within extensional geodynamic environments. Following the lithological classification, the vms deposits are divided in five groups, i. The data was recently used for mineraldeposit density models mosier and others, 2007. The upper cretaceous rocks host the volcanogenic massive sulphide vms deposits in. These vmsdeposit types were adopted on the basis of simplicity of use, greater relevance to map units, and our grade and tonnage models. Chimneys in paleozoic massive sulfide mounds of the urals. Among the three vms subtypes, average silver grades range up to 500 gt sierrecilla, spain in felsic deposits, 603 gt suriana, mexico in bimodal mafic deposits, and 785 gt samatosum, british columbia in.
Pdf metallogeny of volcanogenic massive sulfide vms deposits. Our new models are based on a reclassification of deposits based on host lithologies. In the late cretaceous, early mafic rocks were followed by felsic rock series, and then by upper mafic rocks. Vms deposits can also be effectively classified by their host lithologies. Stratigraphic setting and timing of the montagne dor. These settings are often shalerich siliciclasticfelsic or bimodal siliciclastic. Most, but not all, significant vms mining districts are defined by deposit clusters formed within rifts or calderas. The average silver grade in the felsic vms subtype is significantly higher than that in the bimodal mafic or mafic subtypes table 2. Genetic model of ore deposits mining engineering science. In the urals, a wide range of wellpreserved chimneys are found in vms deposits, which are associated with ultramafic atlantic type.
An overview of petrochemistry in the regional exploration. In developing grade and tonnage models for 1,090 vms deposits, mosier and others 2009 found no significant differ ences between grade and tonnage curves for deposits hosted by pelite mafic and backarc mafic rocks and for deposits hosted by felsicsiliciclastic and bimodal felsic rocks, result ing in their threefold classification of. Felsic, bimodal mafic, and mafic volcanogenic massive sulfide deposits. Vms volcanogenic massive sulphide deposits and nicuco type magmatic. The clast sizes range from large breccia rocks to tuffsize clast.
Zincrich, bimodal felsictype vms deposits are located. Vms deposits have been generated from the archean to the present day, with vms deposits being currently formed on the seafloor. Geochemical investigation of the origin of the back forty. Most zincenriched deposits are vms subtypes that are associated with felsic volcanic andor sedimentary rocks i. Vms lithological classification note the shapes and sizes of sulphide deposits compared to alteration footprint barrie and hannington,1999. Bimodal maficdominated vmshosting calderas include the archean noranda and the paleoproterozoic flin flon mining camps gibson and watkinson, 1990. Volcanogenic massive sulfide occurrence model usgs. Past production at the pick lake mine was 172,956 tons at 9.
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