Large variations in the sulfur isotopic composition of orerelated pyrites in orogenic gold deposits in the eastern goldfields province are the result of different gold. Orogenic gold short course orogenic gold deposits in the superior province of manitoba orogenic gold deposits in the superior province of manitoba scott d. Parameters for the formation of orogenic gold deposits. Pdf orogenic gold deposits are the main source of gold for humanity. Teale2 1 pmdcrc, school of geosciences, monash university, vic 3800, australia. Distribution of trace elements between carbonaceous matter. Epithermal gold deposits part ii geology and gold deposits of the oatman district, northwestern arizona by ed dewitt, jon p. This deposit is a classic example of a lowsulfide turbidityhosted orogenic gold quartz deposit sulfide less than 25% located in the folds of sandstoneshale rock as a saddle reef and as discordant veins and stockwork, predominantly in the anticlinal domes. Potential for new gold deposit discoveries in the palaeozoic miogeosynclinal sedimentary sequences of the tasman geosyncline on both sides of the tasman a province known for its orogenic style turbidite. Orogenic gold deposits account for an estimated 75% of the gold extracted by humans phillips 20, including the tonnage of witwatersrand, the worlds largest district. Controls on the distribution of invisible and visible gold in.
Ftb2 volcanogenic massive sulphide and orogenic gold. Mali suffers from artisanal and smallscale mining formalization problem as other mineral rich countries in the region2. Mesothermal and greenstone gold deposits aka orogenic geology. The wasamac deposit is an example of archean greenstonehosted gold deposit located in the abitibi belt, 15 km southwest of rouynnoranda. Mesothermal and greenstone gold deposits aka orogenic. Mesothermal gold deposits form half way up through the rise of the melt from the deep crust to the surface usually at a depth of less than 10 km but greater than 1 km. These deposits form in response to major orogenic events caused by accretion or changes in subduction direction or dip. A similar deep carbonic source has also been suggested to explain the formation of cm, gold, auriferous pyrite in the sedimenthosted chinese carlintype gold deposits gu et al.
A carbonaceous sedimentary sourcerock model for carlintype. Schematic cross secti on showing the key geologic elements of the main gold systems and their crustal depths of emplacement. In the case of archean and paleoproterozoic deposits, the formation of orogenic gold deposits was one of the last events prior to cratonization. Certain statements in this document constitute forward looking statements within the meaning of section 27a of the us securities act of. Hydrothermal alteration and exploration vectors at the. Carboniferous orogenic gold deposits at pataz, eastern andean cordillera. Structural and lithological controls on bifassociated. Composition and origin of fluids associated with lode gold deposits. The characteristics, origins, and geodynamic settings of. Fluid origin and structural enhancement during mineralization. He explains how orogenic gold formed during plate tectonic collisions and especially during continental growth. The gold resources are concentrated within the 2250 to 2000 ma greenstone belts of the manleo shield, forming the southern part of the west africa craton.
Hyperspectral interpretation of selected drill cores from. Science, research published in the scientific journal neurology shows that people who spend a lot of time for mental exercise demand, like reading, have better memory later on than those who do not read. Predictive targeting in australian orogenicgold systems. Jun 20, 2010 the jinshan orogenic gold deposit is a worldclass deposit hosted by a ductile shear zone caused by a transpressional terrane collision during neoproterozoic time. Orogenic definition of orogenic by the free dictionary.
The archean orogenic new celebration gold deposit, located in the kalgoorlie terrane of the eastern goldfields province, western australia, is hosted within the western segment of the firstorder boulder lefroy fault zone blfz. The qolqoleh gold deposit is one of the most important gold deposits in this gold ore belt. The saramacca gold deposit, a new orogenic gold discovery. Gold deposits can be classified by the nature of the host rock, the genetic model and on the mineral associations related to mineralization. Orogenic gold deposits, or gold deposits in metamorphic rocks, are the spatially and temporally most widespread gold deposit type, defining important exploration targets in precambrian shields and in phanerozoic orogen ic belts. The interplay between physical and chemical processes in. Genesis of orogenic gold deposits involving metamorphic fluids is debatable.
Distribution of orogenic gold deposits in relation to fault. In mali, a less developed country, gold export has substantially increased in the 1990s 1. This includes classic lowsulfidation mesozonal orogenic narrowvein lode gold deposits, represent by mines of the gold hill district gold hilltype and. On the source of orogenic gold geology geoscienceworld. Victoria hosts one of the worlds largest orogenic gold provinces. Orogenic gold deposits are generated at midcrustal 416 km levels proximal to terrane boundaries, in transpressional subductionaccretion complexes of cordilleran style orogenic belts. Models and exploration methods for major gold deposit types. These deposits formed from the archaean to phanerozoic at crustal depths of more than 4 km. The gold resources of mauritania presently include two important deposits and a series of poorly studied prospects.
Orogenictype coppergoldarsenicbismuth mineralization. Structural geometry of orogenic gold deposits sga student. Pacton gold is a canadian exploration company with key strategic partners focused on the exploration and development of high grade conglomerate and orogenic gold properties located in the districtscale pilbara gold rush in western australia and the red lake district, ontario. A brief introduction to orogenic gold deposits gold fields. West africa, with presently an approximate 10,000metric ton t gold endowment, is one of the worlds great gold provinces and the largest paleoproterozoic gold producing region. The island gold mine is an orogenic gold deposit in the. A peculiar feature of these deposits is the association of gold with a variety of copper sulfides and the rare copper arsenides domeykite and koutekite which is atypical for orogenic type gold deposits. This paper presents evidence and arguments that carbonaceous sedimentary rocks were a source for au and as in sedimenthosted orogenic and carlintype gold deposits and develops a corresponding genetic model. Therefore, the interaction of hydrothermal fluids with metamorphosed carbonaceous matter cm could be one of the causes of the reduction of hydrothermal fluids and formation of the respective mineralization 14. Hydrothermal alteration and exploration vectors at the orogenic island gold deposit, michipicoten greenstone belt, wawa, ontario tj ciufo1, c yakymchuk1, s lin1, k jellicoe1, p mercierlangevin2 1department of earth and environmental sciences, university of waterloo, waterloo, ontario. Cassidy proterozoic lode gold and ironcopper gold deposits.
Orogenic gold deposits are gold lodes within and associated with metamorphic belts 1,7,8,9. Both deposits share the main characteristics of orogenic gold deposits. Four eagles, and can help brownfields deliver fosterville, costerfield, ararat. Developing predictive capacity through good science boosts confidence, helps overcome investment notions that victorian gold is maybe too hard. Input data for the present study are existing gold deposits, mapped and interpreted faults, and multiscale. The tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the rgueibat shield and defines a worldclass paleoproterozoic. Structural and lithological study of gold mineralization in. These deposits formed from the archaean to phanerozoic at crustal depths of more than 4. Sixteen common types of bedrock gold deposits are distinguished from one another and their main geological attributes are.
These deposits formed from the archaean to phanerozoic at crustal. Deposition of trace elements between cm3, py5a and py5b. The saramacca gold deposit, a new orogenic gold discovery in. Gold in 2000 contents gold in 2000an introduction s. Timing, nature and characteristics of orogenic gold deposits. Significantly higher densities of pathways in areas surrounding larger gold deposits are measurable within 20 and 5kilometer search radii around them. A proposed classification in the context of their crustal distribution and relationship to other gold deposit types, authordavid i. We invite contributions on all aspects of geochemistry applied to these intriguing deposits. A proposed classification in the context of their crustal distribution and relationship to other gold deposit types. Orogenic gold deposits are the main source of gold for humanity. Ore bodies at the deposit include laminated quartz veins and disseminated pyritebearing mylonite. Orogenic gold, or gold deposits in metamorphic rocks, and associated placer deposits, comprise about 6575 percent of this endowment, with lodes existing as structurallyhosted vein and or disseminated orebodies.
A rational geological classification of the commonly recognized lode gold deposits is feasible if it is based on the geological settings of the deposits, host rocks, nature of mineralization and geoche mical signature. Deposits can range from single small quartz veins to large and commonly highgrade, faultshear controlled systems containing in excess of 25 million ounces of gold. Gold deposition is accompanied by carbonation, sulphidation and muscovitebiotite alteration where the host rock is of suitable bulk composition. The term mesothermal veins is really a sack term, referring simply to the depth formation. Distribution of orogenic gold deposits in relation to. These were first filtered to remove duplicates and non gold occurrences. Gold deposits in polydeformed metasedimentary rocks. Open file report 201816 november 9, 2018 suggested citation.
Orogenic gold deposits of china society of economic. These are dominated by orogenic gold deposits that were put in place during the major orogenies. Phillips and powell 2011 either as the erosion of primary gold deposits or from hydrothermal. The late timing of orogenic gold deposits within the structural evolution of the host orogen implies that any earlier structures may be mineralized and that the current structural geometry of the gold deposits is equivalent to that at the time of their formation provided that there has been no signi. Diamond drill cores from seven orogenic gold deposits in central victoria were scanned using the csirodeveloped hyloggingtm system to obtain visible to near infrared vnir, swir and thermalinfrared tir hyperspectral data in 2007 as. The saramacca gold deposit, a new orogenic gold discovery in the guiana shield amec round up 2018, vancouver l tsx. And not only that, we also have to read high for our children. The deposit is hosted by a secondorder ductile shear zone of the cadillaclarder lake fault zone cllfz. Detailed material for this globally important deposit type will be provided on tectonic and structural controls. Anderson mineral deposits geologist manitoba geological survey scott d.
The main orogenic gold deposits are strongly associated with deformed metamorphic terranes, and gold is commonly related to greenschist facies rocks groves et al. Phillips and powell either as the erosion of primary gold deposits or from hydrothermal accumulation. Traceelement geochemistry of pyrite and arsenopyrite. Vein, stockwork and disseminated gold deposits are very common within orogenic belts, providing a large percentage of total historical world and australian gold production. A series of gold deposits such as qolqoleh, kervian and qabaqloujeh are distributed in this ductilebrittle shear zone, and form a nesw. Feb 26, 2019 orogenic gold deposits are the main source of gold for humanity. These deposits formed from the archaean to phanerozoic at crustal depths of. With very few exceptions, orogenic gold deposits formed in subductionrelated tectonic settings in accretionary to collisional orogenic belts from archean to. Six orogenic gold deposits constitute the yangshan gold belt in the west qinling orogen. The key to a unified model for orogenic gold deposits. Some of the properties are available for option from prospectors or as joint ventures with junior mining companies. These gold deposits, combined with gold panning and artisanal mining, underscore the highly m pro ising character of the area. This remarkable association is clearest in circumpacific mesozoic to cenozoic deposits but is also apparent innorth american, australian and soviet paleozoic deposits within the orogenic belts. Gold has historically been a key strategic commodity, and the study of gold deposit formation has long been investigated.
The correlation of major gold deposits with rock type, even when the gold is primarily in veins, argues for rock. The laramide caborca orogenic gold belt of northwestern. Orogenic gold short course manitoba mining and minerals convention 2008. Banded iron formation bifassociated gold deposits, a subtype of orogenic lode gold deposits, are structurally controlled at all scales, ranging from the distribution of deposits along major structures to the internal textures and structures of the ore. Nov 10, 20 dr richard goldfarb is a world expert on orogenic gold deposits.
Some of the figures of the pdf file of this article are of poor quality. Aspects of resource geology in archaean orogenic gold deposits. Timing, nature and characteristics of orogenic gold. Glennie lake mapping and general comments on orogenic gold in. Prospectivity analysis of orogenic gold deposits in saqez. Smith2 abstract mines in the oatman mineralized district, near oatman in northwestern arizona, have produced more than 1.
There are six worldclass settings for magmatichydrothermal gold deposits. This setting contrasts with the majority of orogenic lode gold deposits worldwide, which are. Good science, good exploration, can find new deposits eg. In the above orogens, isotopegeochronological estimates suggest that the ore deposits were formed late in the orogenic history or even after orogeny had demonstrably ended 3,4,10,11. Detailed textural and traceelement analysis of sulfides in terms of a newlyerected paragenetic sequence for these deposits, together with previously. Orogenic gold mineralization in the qolqoleh deposit. He explains how orogenic gold formed during plate tectonic collisions and. Glendon and robbins aes alignments in the carolina terrane. Neighbouring orogenic gold deposits may be the products of.
Gold history and genesis of deposits convert bundle as. Because of this, the depth zones for these orogenic subclasses do not correspond to those in lindgrens epithermal, mesothermal, and hypothermal regimes. Pyrite compositions from vhms and orogenic au deposits in. Carlintype gold deposits in nevada, usa, although characterized by aqueouscarbonic. Orogenic gold deposits represent by far the most economically important primary gold mineralisation in victoria, accounting for almost all primary gold production more than 1100 tonnes and include most of the known and potential resources.
Gold is mostly invisible in solid solution or in the sulfide lattice, with minor visible gold associated with stibnite and in quartzcalcite veins. Such an assumption is valid because this deposit type is, by far, the most dominant gold deposit type in the studied craton. The main objective of this report is to present the sample locations, 40ar39ar experimental methodology, and ar39ar isotopic data tables 14. Orogenic gold deposits in the superior province of manitoba.
The abundance of orogenic gold deposits reflects paleozoic to triassic. Controls on the distribution of invisible and visible gold. Brief overview of the geology of the sw reindeer zone results of 2017 mapping. Introduction to orogenic gold deposits investing news network november 23rd, 2014 orogenic deposits are the source of much of the worlds gold. Gold deposits can still be seen today forming in some active geothermal areas. Volcanogenic massive sulphide and orogenic gold deposits in northern southeast alaska. It is critical to note that this terminology has been defined solely as a subdivision for orogenic gold deposits based on many modern geothermobarometric studies. Models and exploration methods for major gold deposit types robert, f. Gold in the orogenic gold deposits of the yangshan.
Prospectivity analysis of orogenic gold deposits in saqezsardasht goldfield, zagros orogen, iran by a. Sawyerkeystone trend of auagas deposits in randolph county. Porphyry deposits occur in two main settings within the orogenic belts. Debate on the genesis of socalled orogenic gold deposits 75% of gold recovered through history.
Glennie lake geology and structure general comments on orogenic gold deposits and some suggestions on. This study presents data on the geological setting and ore mineralogy of these deposits. Pdf from intrusionrelated to orogenic mineralization. Dr richard goldfarb is a world expert on orogenic gold deposits. Structural and lithological study of gold mineralization. Subducted oceanic slab with overlying sulfiderich sedimentary package, or mantle. Mineral potential tracts for orogenic, carlinlike, and. The distribution of au and associated trace elements in pyrite and arsenopyrite from late archean hutti and hirabuddini orogenic gold deposits, eastern dharwar craton, southern india was investigated by laser ablationinductively coupled plasmamass spectrometry. Predictive targeting in australian orogenic gold systems at the deposit to district scale using numerical modelling w. Bsc hons university of wales, cardiff msc university of wales, cardiff in december 2005. Macraes orogenic gold deposit new zealand origin and development of a world class gold mine caption. Diversity of gold deposits, geodynamics and conditions of. Crowe a comparison of australian and global examples. Pdf parameters for the formation of orogenic gold deposits.
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