Codes the australian research councils centre for excellence in ore deposit research, university of tasmania, private bag 126, hobart, tasmania 7001, australia. Porphyry deposits are the worlds most important source of cu and mo, and are major sources of au, ag, and sn. Porphyry deposits showing potential for hightonnage, low. Sillitoe rh 1993 gold rich porphyry copper deposits geological model and from geol 562 at university of kansas. Mineralogy and mineral chemistry of the cretaceous duolong. In porphyry copper deposits, copper ore minerals are disseminated in igneous intrusions. Role of porphyry models in explora 317 o 320 gt8 ppm cuau 035 au34 0 24co 027. Formed at relatively shallow depths in the earths crust less than 15,000 to 30,000 feet in areas characterized by high rates of. Learn how to find rich gold deposits in porphyry, we are going to be talking about that in great depth and the associated geology with porphyry, copper porp. Estimate of undiscovered copper resources of the world, 20. Gold distribution in porphyry copper deposits of kerman region. Oct 01, 2002 gold abundances in porphyry copper deposits vary greatly, complicating efforts to define goldrich porphyry copper deposits.
Porphyry copper deposits in europe are paleozoic and late cretaceous to miocene in age. Associated with late cretaceous subvolcanic bodies and porphyry dikes intruded into cambrian metamorphic rocks and carboniferous granodiorites. Sillitoe rh 1993 gold rich porphyry copper deposits. Goldrich porphyry copper deposits of cenozoic are dominantly generated in subductionrelated volcanoplutonic arcs and continental maragin arc at convergent. In general, porphyry deposits are characterized by low grades of ore mineralization, a porphyritic intrusive complex that is surrounded by a vein stockwork. These ore bodies range from around 10 million to 4,000 million tonnes of contained ore, and have a grade of between 0. Gold rich porphyry deposits worldwide conform well to a generalized descriptive model. Pdf platinumgroup element potential of porphyry deposits. Advances in geological models and exploration methods for. Porphyry cu and porphyry mo deposits are large to giant deposits ranging up to 20 and 1. Characteristics and controls of the largest porphyry copper.
Detrital gold grains as indicators of alkalic copper gold. Copper hill is an unusual porphyry copper gold deposit in that palladium is enriched over intervals of tens of metres in some drill holes. Porphyry cu systems host some of the most widely distributed mineralization types at convergent plate boundaries, including porphyry deposits centered on intrusions. Copper porphyry deposits can range from 10s of millions in metric tons mt to more than 1 billion mt of ore. Some thoughts on goldrich porphyry copper deposits springerlink.
The duobuza goldrich porphyry copper district is located in the bangongco metallogenetic belt bgcmb, fig. Kirkham and sinclair defined goldrich porphyry copper deposits as those with cuwt. Porphyry indicator minerals pims and porphyry vectoring. Iron oxide copper gold iocg deposits are considered to be metasomatic expressions of large crustalscale alteration events driven by intrusive activity. A brief discussion of the porphyry copper subtypes is in the appendix. Qtzsericitepyrite qsp is not exclusively associated with porphyry copper. Gold paragenesis and chemistry at batu hijau, indonesia. Geology and hydrothermal alteration of the duobuza gold. Deposits resulting from the oxidation, enrichment, and chemical transport of copper and zinc and mechanical transport of gold and silver during supergene weathering are also briefly highlighted. The original definition was based on the aumo ratios of porphyry copper deposits with no reference to their copper content, and resulted in the suggestion that goldrich deposits were found largely in island arc regions kesler, 1973. Porphyry copper deposits represent an important resource and the dominant source of copper that is mined today to satisfy global demand. Sep 10, 2004 gold is an important byproduct in many porphyry type deposits but the distribution and chemistry of gold in such systems remains poorly understood.
Porphyry copper deposits account for about 60 percent of the worlds copper. There are also examples of continental arc and postcollisional porphyry deposits in new guinea. Initial studies focussed on the suite of rock forming minerals e. Geologic characteristics and exploration significance of. Gold is an important byproduct in many porphyry type deposits but the distribution and chemistry of gold in such systems remains poorly understood. The au rich trend is essentially controlled by the seven largest gold deposits containing almost the 60% of the gold of porphyry cu au. Basic characteristics of goldrich porphyry copper deposits and their.
However, pbznag may be fringe to arsenical tennantite stage 4 copper veins. Pdf gold distribution in porphyry copper deposits of kerman. Porphyry indicator minerals pims and porphyry vectoring and. Pages 62 ratings 100% 1 1 out of 1 people found this document helpful. Distribution of worlds porphyry copper deposits modified from singer et.
Iron oxide copper gold ore deposits iocg are important and highly valuable concentrations of copper, gold and uranium ores hosted within iron oxide dominant gangue assemblages which share a common genetic origin. Covered by 100m of clayrich transported alluvium, the marsden calcalkalic porphyry copper gold deposit was discovered in 1997 by newcrest mining ltd. Pdf distribution of gold in porphyry copper deposits. Experiments in the system aucufes were carried out at temperatures of 400 to 700c to determine how much gold could be accommodated by bornite and chalcopyrite, the two most common ore minerals in porphyry copper gold deposits. The aurich trend is essentially controlled by the seven largest gold deposits containing almost the 60% of the gold of porphyry cuau. Preliminary model of porphyry copper deposits usgs. Some au rich porphyry cu deposits have relatively high contents of. It has been particularly productive for goldrich porphyry deposits. A number of the 31 known phanerozoic deposits contain more than 1 million metric tons of contained. One feature of porphyry copper deposits in the phil. Byproducts of porphyry copper and porphyry molybdenum deposits commodity deposit type locationparagenesis higher re contents of mineralogy grade examples escondida notes references silver porphyry cu alkaline rocks mostly in central cumostly in solid solution copper porphyry discovery closely similar in genesis, host rock types, alteration and mineralization to several important british columbia mines, including the copper mountain, mt polley, mt milligan, and red chris operating mines but distinct from valley copper and gibraltar calcalkalic. This model incorporates six main facies of hydrothermal alteration and mineralization, which are zoned upward and outward with respect to composite porphyry stocks of cylindrical form atop much larger parent plutons. Committee for coordination of joint prospecting for mineral resources in asian offshore areas ccop, ccop technical publication 14, 89 p.
Gold abundances in porphyry copper deposits vary greatly, complicating efforts to define goldrich porphyry copper deposits. This report contains a revised descriptive model of porphyry copper deposits pcds, the worlds largest source about 60 percent and resource about 65 percent of copper and a major source of molybdenum, gold and silver. Characteristics and controls of the largest porphyry. The margins range from primitive, through mature island arcs to continental margins.
F the southwest pacific contains numerous porphyry copper gold deposits that formed in oceanic island arcs in the philippines, indonesia and png. Gold endowments of porphyry deposits controlled by precipitation. Granodiorite porphyry and quartz diorite porphyrite are the main ore. Curichversus aurichporphyries aurich curich goldrich copper rich chiaradia 2020 gold endowments of porphyry deposits controlled by precipitation efficiency.
Porphyry deposits represent an important resource of copper. Particular emphasis is placed on the potential for exceptionally high grade porphyry copper, porphyry gold, epithermal gold, and subvolcanic tin deposits. This high tonnage of mineralized rock and the associated long mine life that can span. Cargo porphyry cuau deposit where is the high grade core.
It has a total mineable ore reserve of 353 million tons at 0. Two main goldrich porphyry copper deposits and an received 31 august 2010. Porphyry copper assessment of europe, exclusive of the. Geochemical characteristics of intrusive rocks, southeastern. Magnetite is an important vein and alteration mineral in the highgrade core of some goldrich deposits, and can locally comprise up to 10 wt. Significant pd and pt contents in only certain porphyry copper deposits worldwideas described in the appendix to this article, certain porphyry cuau deposits have elevated pdpt contents, including copper mountain, allard stock, copper king mt milligan, galore creek, ajaxafton, skouries, elatsite, santo tomas ii and mamut table 10 1, werle. The geological characteristics, geochemical signature and.
The deposit type was first recognised by discovery and study of the supergiant olympic dam copper golduranium deposit olympic dam mine, and south american examples. Rich gold deposits in porphyry geology 101 ask jeff. Minor amounts of rhenium, tellurium, arsenic, zinc and platinum group elements are also present in elevated concentrations within these systems and are recovered at some mining operations. Chapter 7 byproducts of porphyry copper and molybdenum deposits. Gold is normally present in potassium silicate alteration, which commonly carries an unusually high magnetite content. Most intrusionrelated gold deposits are generated above zones of active subduction at convergent plate margins. Gold endowments of porphyry deposits controlled by. Pdf gold distribution in porphyry copper deposits of. Pdf analysis of 55 porphyry copper deposits demonstrates a continuum between porphyry copper gold deposits emplaced at a median depth of 1 km, with a. Future exploration for arizona porphyry copper deposits. Pbznag is not a zoning fringe of stage 3 porphyry copper plutons 4. Department of mining geology, royal school of mines, imperial college of science and. Macdonald, in handbook of gold exploration and evaluation, 2007 2.
Geology and hydrothermal alteration of the duobuza goldrich. Analysis of 55 porphyry copper deposits demonstrates a continuum between porphyry copper gold deposits emplaced at a median depth of 1 km, with a median size of 160 million metric tons of copper. Porphyry deposits are the worlds principal resources of cu, mo, and re, and are major. Associated deposit types a variety of deposit types are spatially, if not genetically, related to porphyry copper mineralization, including skarns, polymetallic veins and replacements, and epithermal veins. In contrast, porphyry copper and goldrich copper porphyry deposits are associated with a wider range of intrusive compositions, from diorite or quartz diorite to quartz monzonite sillitoe, 2000. Gold paragenesis and chemistry at batu hijau, indoneisa. Geology and hydrothermal alteration of the duobuza. Sedimenthosted stratabound copper deposits, in which copper is concentrated in layers in. Some thoughts on goldrich porphyry copper deposits. Geological survey usgs collaborated with european geologists to assess resources in porphyry copper deposits in europe, exclusive of scandinavia sweden, denmark, norway, and finland and russia. Porphyry copper deposits result from the complex interactions and feedbacks of. Jan 14, 2020 porphyry copper gold deposits are large volume, lowgrade disseminations formed by precipitation of copper and gold plus molybdenum from fluids of magmatic origin 1.
Porphyry copper deposits are also important sources for other metals, including molybdenum, gold and silver. Kirkham and sinclair defined gold rich porphyry copper deposits as those with cuwt. The christmas copper deposit, located in southern gila county, arizona, is part of the major porphyry copper province of southwestern north america. The hat project lisle zone is an alkalictype gold copper porphyry discovery closely similar in genesis, host rock types, alteration and mineralization to several important british columbia mines, including the copper mountain, mt polley, mt milligan, and red chris operating mines but distinct from valley copper and gibraltar calcalkalic. Calderas are not related to porphyry copper deposits 3. Sillitoe 27 west hill park, highgate village, london n6 6nd, england abstract porphyry cu systems host some of the most widely distributed mineralization types at convergent plate boundaries, including porphyry deposits centered on intrusions. Few porphyry copper deposits are greater than 340 million years old. Chapter 7 byproducts of porphyry copper and molybdenum. New prosperity gold copper porphyry deposit model 15 emerson 50 km2 and goathorn 17. Copper skarn deposits occur near many porphyry copper host intru. It refers to large, relatively low grade, epigenetic, intrusionrelated deposits. Gold contents of the kerman porphyry copper deposits are generally low, ranging from 0. Some thoughts on goldrich porphyry copper deposits nasaads.
The copper ores exhibit cuau atomic ratios much greater than 40000, and aumo ratios below 30, which signifies them as goldpoor porphyry copper deposits. The major products from porphyry copper deposits are copper and molybdenum or copper and gold. The term porphyry copper now includes engineering as well as geological considerations. Geological survey, denver federal center, ms 973, box 25046, denver, colorado 80225. Sillitoe, 1979, being arbitrary defined by sillitoe 1979 as those porphyry copper deposits that contain over 0. Sillitoe, 1979, being arbitrary defined by sillitoe 1979 as those porphyry copper deposits. Byproducts of porphyry copper and molybdenum deposits. The application of indicator methods to exploration for concealed porphyry deposits has become increasingly sophisticated in recent years. Gold rich porphyry copper deposits of cenozoic are dominantly generated in subductionrelated volcanoplutonic arcs and continental maragin arc at convergent. Based on the available data from many porphyry copper deposits, kesleret al.
It is currently being explored and managed by benguet corporation. Geology and porphyry coppertype alterationmineralization of. Pdf distribution of gold in porphyry copper deposits researchgate. Controls on the formation of porphyry copper and gold deposits. Although christmas is known for skarn deposits in paleozoic carbonate rocks, oregrade porphyry type copper mineralization also occurs in a composite granodioritic intrusive complex and adjacent mafic volcanic country rocks. The systems commonly define linear belts, some many.
Goldrich porphyry deposits worldwide conform well to a generalized descriptive model. The goldpoor signature of the kerman deposits complies with features such as higher contents of chalcopyrite and pyrite over bornite. These deposits form from hydrothermal systems that affect 10s to 100 km3 of the upper crust and result in enormous mass redistribution and potential. Pdf analysis of 55 porphyry copper deposits demonstrates a continuum between porphyry coppergold deposits emplaced at a median depth of 1 km, with a. Gold distribution in porphyry copper deposits of kerman. Here we report the results of petrographic, electron microprobe, laser ablation inductively coupled plasma mass spectrometry laicpms, and flotation test studies of gold and associated copper sulfides within a paragenetic framework from the.
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