After doing an extensive literature survey at the best university library i find these exploration methods. Geological survey usgs completed assessments for undiscovered resources of porphyry and sedimenthosted copper, platinumgroup elements, and potash. Each deposit type is coded type as appropriate deposit type number as listed in usgs. An additional 12% of the copper is in sedimenthosted copper deposits. The usgs assessed undiscovered copper in two deposit types that account for about 80 percent of the worlds copper supply. The great porphyry copper deposits of arizona geology for. These are large scale magmatichydrothermal systems associated with a series of porphyritic intrusions, which result in extensive alteration footprints that we map and model to target high grade copper gold mineralization.
Characteristics of porphyry aucu systems in the ordovician macquarie arc of nsw bruce mowat, goldminco, mitchell hwy, orange nsw 2800 stuart smith, oxiana ltd, 9th floor, 31 queen st, melbourne, vic 3000 key words. Prospective features encountered in exploration work include arctype volcanic rocks, copper. Gold abundances in porphyry copper deposits vary greatly, complicating efforts to define goldrich porphyry copper deposits. Porphyry ore typically forms in magmatic arcs above subduction zones.
Characteristics of porphyry aucu systems in the ordovician. Just two deposit types, porphyry copper and sedimenthosted copper, account for over 80% of all known copper. This report contains a revised descriptive model of porphyry copper deposits pcds, the worlds. The radiometric survey its important to discover the alteration k u t. Generation of porphyry copper deposits by gasbrine. Cross section of a porphyry copper deposit showing idealized alteration. Locations of all porphyry copper deposits in the porcu. Hydrothermal alteration of the rocks of the morenci porphyry copper deposit is well described in lindgren 1905a, reber 1916, bennett 1974, preece, stegen and weiskopf 1993, and walker 1995. Copper skarn deposits occur near many porphyry copper host intru. Thomson resources has two areas considered prospective for the porphyry coppergold style in the northeast part of the tenement package at warraweena and tringadee, where alteration and mineralisation have been intersected in drilling. Usgs bulletin 1857e tooker, edwin wilson, james, l. Permissive tracts for porphyry copper deposits in central america and the caribbean. Mercer2 1 department of geological sciences, 1272 university of oregon, eugene, oregon 97403.
Porphyrytype copper deposits research papers academia. 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. To order this and other usgs information products, visit any use of trade. In porphyry copper deposits, copper ore minerals are disseminated in. Now in the first exploration geology course i discussed how because our current mining technology all the metals that we use are mined from the top 4 km of the earths crust. Porphyry copper deposits, which are associated with igneous intrusions, yield about. Some authorities consider the expression porphyritic rock better usage than porphyry, since the term refers only to the texture of the rocknot its chemical, physical, or mineralogical composition or color. I also showed why with the crustal abundance or the average crustal. For an overview of usgs information products, including maps, imagery, and publications. Arcgis was used to spatially assess and rank potential porphyry copper deposits using advanced spaceborne thermal emission and reflection radiometer aster data together with geochemical and geologic datasets in order to estimate undiscovered deposits in the southern basin and range province in the southwestern united states. Ip survey can used for the sulfide mapping not for porphyry copper. Porphyry copper deposits commonly contain hundreds of millions of metric tons of.
Start this article has been rated as startclass on the projects quality scale. The sombrero butte breccia pipe system is located at the southern end of the copper creek bunker hill mining district in the laramide porphyry copper province of southwestern north america titley, 1982. Porphyry deposits are one of the most important sources of copper and molybdenum, and are also major sources of silver, gold, and tin. Geology of the tanama and helecho porphyry copper deposits and vicinity, puerto rico. Porphyry copper assessment of central america and the caribbean. Copper is usually found in nature in association with sulfur. Porphyry copper deposit model free download pdf ebook. Geology of the tanama and helecho porphyry copper deposits. Understanding the global distribution of nonfuel mineral resources. Generation of porphyry copper deposits by gasbrine reaction. For best results viewing and printing pdf documents, it is recommended that you download the documents to your computer and open them with adobe reader.
Porphyry copper deposits are very large mineralized. Porphyry copper deposit modelscientific investigations report 20105070b u. Part or all of this report is presented in portable document format pdf. Insights from titanium diffusion in quartz celestine n. For sale by the books and openfile reports section, description. A 1998 usgs assessment estimated 550 million tons of copper contained in identified and undiscovered resources in the united states. What investors need to know about porphyry copper deposits.
Thomson resources porphyry copper gold deposit model. The potential for porphyry coppermolybdenum deposits in the eastern united states. The copper flat porphyry copper deposit in the northern part of the hillsboro district was discovered in 1975 castellano et al. The speciation of sulfur is controlled by oxygen fugacity. The potential for porphyry coppermolybdenun1 deposits in the. Uses of copper supply, demand, production, resources. Porphyry copper potential of the united states southern. The copper hill porphyry copper gold project summary the copper hill cuau deposit contains 535,000 tonnes of copper and 1. Here lets understand the geology of porphyries and iron oxide copper gold deposits or iocg as they are known. Therefore, porphyry cu deposits are usually oxidized with oxygen fugacities.
These are somewhat the giants of the ore deposits world. Porphyry copper deposits account for about 60 percent of the worlds copper. Porphyry copper deposits, that is, copper ore associated with hydrothermal fluids rising from a magma chamber, supply 75% of the worlds copper. This model of porphyry copper deposits is part of a.
Database and grade and tonnage models, 2008 by donald a. Breccias associated with porphyry copper deposits have been a source of fascination for many researchers. If you would like to participate, you can choose to edit this article, or visit the project page for more information. The manual method to cusmap mineral assessment was used by pratt. In porphyry copper deposits, copper ore minerals are disseminated in igneous intrusions. Some porphyry copper deposits in oceanic crust environments, such as those in the philippines, indonesia, and papua new guinea, are sufficiently rich in gold that they are called coppergold porphyry deposits.
Identified resources of porphyry copper deposits in eastern australia 19. As a mining interested learner, the geology of porphyry copper deposits is vital to your education now in the first exploration geology course i discussed how because our current mining technology all the. Porphyry copper assessment of eastern australia usgs. Mar 29, 2018 porphyry copper deposit modelscientific investigations report 20105070b u. Porphyry copper deposit model, chapter b of mineral deposit.
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. Singer and others published porphyry copper deposits of the. Porphyry copper gold deposits form in a variety of volcanic environments, most commonly in continental margins and intraoceanic arcs. Byproducts of porphyry copper and molybdenum deposits. Information on porphyry copper deposits from around the world with grade and tonnage models, a general classification based on geologic setting, mineralogy, with data allowing locations of these deposits to be plotted using gis. The formation of porphyry copper deposits springerlink. Seal porphyry copper deposits result from the complex interactions and feedbacks of many.
Porphyry coppermolybdenum deposits pcds are the worlds most. A careful compilation of 1978 copperbearing mineral deposits totals 2700 million metric tons of copper including past production, which is considerably more than reported in previous studies singer, 1995, mudd et al. These usgs studies are part of a nationwide research project on evaluating and detecting concealed mineral resources. Porphyry copper deposit, large body of rock, typically a porphyry of granitic to dioritic composition, that has been fractured on a fine scale and through which chalcopyrite and other copper minerals are disseminated. This usgs publication has been superseded by openfile report 20051060. Geophysical signatures of coppergold porphyry and epithermal gold deposits, and implications for exploration thesis submitted by terence hoschke, bsc hons submitted in partial fulfilment of the requirements for the degree of master of science exploration geoscience university of tasmania june, 2010. Dunn, 1982, 1984, although alteration and mineralization in the area suggested to earlier geologists that a porphyry copper deposit should occur in the district kuelmer, 1954. Part or all of this report is presented in portable. Copper is a moderately incompatible chalcophile element. Pure copper metal is generally produced from a multistage process, beginning with the mining and concentrating of lowgrade ores containing copper sulfide minerals, and followed by smelting and electrolytic refining to produce a pure copper cathode. View porphyrytype copper deposits research papers on academia. The mines were chosen based on an operating record of more than five years.
Porphyry ore deposits are the source of much of the copper, molybdenum, gold and silver used by humans. These deposits include worldclass copper porphyry and skarn deposits as well as a continuum of similar skarn, porphyry, vein, and replacement deposits that contain variable quantities of molybdenum, zinc. Ray mine, arizona, one of the largest porphyry copper deposits in the united states. Porphyry copper deposit is part of wikiproject geology, an attempt at creating a standardized, informative, comprehensive and easytouse geology resource. The us geological survey has classed the chorolque and catavi tin deposits in bolivia as porphyry tin deposits. Pakistan geological survey mineral information series 9, 21 p. Oct 17, 2019 the lowell and guilbert model of porphyry copper deposits based on arizona examples these deposits have been scientifically studied since the 1900s by the usgs and this in depth study over a long period of time has made this region the type area for the description of porphyry copper deposits. Porphyry copper potential of the united states southern basin and range using aster data integrated with geochemical and geologic datasets to assess potential nearsurface deposits in wellexplored permissive tracts. In addition, porphyry deposits may host valuable by. Geological survey, 520 north park avenue, tucson, arizona 85719, usa. For best results viewing and printing pdf documents, it is recommended that you download the documents to your computer. Because some porphyry mo deposits contain significant w, the few papers that document mow and w porphyry deposits are also provided in this subsection. Porphyry copper deposits of the american cordillera. The porphyry copper deposits of the region have been not only sites of recovery of significant mineral wealth but also sites of detailed and extensive studies of process geology and develop ment of mining and beneficiation technology.
Mar 15, 2017 porphyry deposits, our main source of copper and of significant amounts of mo, re and au, form at convergent margins in association with intermediatefelsic magmas. Byproducts of porphyry copper and molybdenum deposits rare. The copper hill porphyry coppergold project summary the copper hill cuau deposit contains 535,000 tonnes of copper and 1. Porphyry deposits are the worlds principal resources of cu, mo, and re, and are major resources of au and ag. Based on statistics in the united states geological survey usgs database of worldwide porphyry copper deposits, the 2008 median grade of 422 porphyry copper deposits was 0. Porphyry copper potential of the united states southern basin. Porphyrystockwork deposits of copper, molybdenum, and tungsten.
As a mining interested learner, the geology of porphyry copper deposits is vital to your education. Geological studies of mining districts of the southwest reported mostly by geologists. What the best geophysical survey method for exploring and discovering a porphyry copper deposit. Usgs mineral resources program coppera metal for the ages. Geological survey usgs report estimated that 550 million tons of copper were contained in identified and undiscovered resources in the united states. The 14 mines represent 87% 14 out of 16 of currently operating copper porphyry mines, and 89% of u. Descriptions of the tertiary volcanic and sedimentary rocks are primarily derived from recent mapping by ferguson and enders this report. 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.
Critical metal particles in copper sulfides from the. Preliminary model of porphyry copper deposits usgs. In addition, porphyry deposits may host valuable byproducts. Porphyry copper deposit exploration and resource assessment objectives.
Porphyry cu and porphyry mo deposits are large to giant deposits ranging up to 20 and 1. Since 1905, more than 700 articles concerning porphyry deposits have been published by the society of economic geologists in its various publications economic geology. Porphyry coppergold deposits form in a variety of volcanic environments, most commonly in continental margins and intraoceanic arcs. In response to the growing demand for information on the global mineralresource base, the u. The usgs assessed undiscovered copper in two deposit types that account. Information on porphyry copper deposits from around the world with grade and tonnage models, a general classification based on geologic setting, mineralogy, with data allowing locations of. 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.
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