Geology, national institute of geological sciences. 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. Supergene mineralization of the medvedin uranium deposit, krkonose mountains, czech republic jakub plasil1,2, jiri sejkora1, jiri cejka1, radek skoda3, viktor golias2 1 department of mineralogy and petrology, national museum, vaclavske nam. The bir tawilah gold deposit in central western saudi arabia represents a panafrican example of gold mineralization in which both hypogene and supergene ores are recorded. Codes the australian research councils centre for excellence in ore deposit research, university of tasmania, private bag 126, hobart, tasmania 7001, australia. Crystal features of supergene gold at hannan south, western australia. Pdf the bir tawilah deposit, central western saudi arabia. Gold mineralization originated mainly during middle and late stages, particularly in. The bir tawilah deposit, central western saudi arabia. Structural and lithological study of gold mineralization. Pilot gold drilled two holes krd002 and krd004 to target cuau porphyry. Two principal associations of the supergene minerals were observed.
This study demonstrates, for the first time, that supergene copper mineralization presents a chronological potential and can be dated, at least in some case, by the uthpb method. The nagambie gold deposit, central victoria, australia, consists of approximately 7 million metric tons of ore averaging 1. Dos pobres is unusual among arizona porphyry deposits in that it is relatively gold and borniterich, and magnetitebearing and is intimately associated with relatively. Magmatic, hydrothermal, and supergene characteristics of two adjacent porphyry systems. Pdf the bir tawilah deposit, central western saudi. Mcmoran copper and gold, was undertaken with the twin goals of characterizing the mineralogy and distribution of precious metals in the hypogene mineralization and developing insight into the possible reasons for the unusual metal endowments in this atypically for. Day abstract the canadian segment of the archean superior province is a major world source of lode gold. Furthermore, the age obtained on pseudomalachite indicates that mina sur deposition took place at ca.
The deposit occurs beneath an ephemeral lake system and is at least partially saturated by highly saline groundwater. The supergene enrichment of gold in deposits may take place by a simple mechanical process, by chemical means, or by a combination of these. Supergene enrichment how natural processes have transformed. The regional landscape consists of three land surface units with respective altitudes of 300 m, 280 m and 265250 m. Supergene mineralisation of the boyongan porphyry copper gold deposit, surigao del norte, philippines by allan maglaya ignacio b. Supergene mineralisation of the boyongan porphyry coppergold deposit, surigao del norte, philippines by allan maglaya ignacio b. In this study we assess the link between surface morphologies of au grains and supergene transformation processes, with a focus on the formation of nanoparticulate au in temperate settings. Relationship between magmatism and mineralization in the. The lateritic weathering process of precambrian albitite formations containing gold sulphide mineralization has been studied at larafella, southern burkina faso. Figure 2 shows the general succession of sulfide mineral destruction by chalcocite replacement, as observed from paragenetic relationships shown by oxidesul. Current inferred mineral resources for boyongan are estimated at 219 million tonnes of combined oxide and sulfide material with an average grade of 0. Relationship between magmatism and mineralization in the rbm gold deposit, white pine county, nevada a thesis submitted in partial fulfillment of the requirements for the degree of master of science in geology by daniel w.
Nov 01, 2006 the dimakomboscorro lode gold deposit has two styles of mineralization. Metavolcanic host rocks, mineralization, and gossans of. Geologic controls on hypogene mineralization at the zaldivar porphyry coppergoldmolybdenum deposit, escondida district, northern chile metals, minerals, and society cerro verdesanta rosa coppermolybdenum deposits, peru. On the basis of textural features and spatial distributions, both supergene and hypogene origins have been proposed for alunite in sedimenthosted micron gold deposits. Mcqueen crc leme, australian national university, canberra, act 0200 and school of rehs, university of canberra, act 2601. Boyongan is a blind coppergold porphyry deposit that was discovered by anglo american exploration philippines, inc. Hence not only the iron have high carbon when he was in very brittle they these problems he put even spiritual concepts of. Supergene sulfide enrichment, in geology, natural upgrading of buried sulfide deposits by the secondary or subsequent deposition of metals that are dissolved as sulfates in waters percolating through the oxidized mineral zone near the surface. Relationship between magmatism and mineralization in the rbm gold deposit, white pine county, nevada. Supergene ore and hypogene subeconomic gold mineralization at shewushan, hubei, central china article in applied earth science imm transactions section b 1093. The main portion of this book is a revision of a stenographic record of the lecture course on groundwater geology which has been given at stanford university since 1927, and prior to that in the. Mineralization at gandy occurs in close spatial relation with rhyolitic domes in a caldera setting in a series of narrow brecciated veins. Structural and lithological study of gold mineralization in. Textures and fabrics is a collection of papers that deals with economic geological deposits, particularly as endogenic type, or as an integral part of their geological environment.
The gandy goldbase metal deposit is located in tertiary torudchahshirin volcanoplutonic range, north of central iran. Request pdf supergene ore and hypogene subeconomic gold mineralization at shewushan, hubei, central china the shewushan gold deposit in the south of the jianghan plain in hubei, china fig. Deep weathering of basalthosted sulphidic gold mineralisation has resulted in remobilisation of the gold and the formation of a supergene deposit. Read the bir tawilah deposit, central western saudi arabia. Introduction ore deposits are crustal concentrations of useful elements that can be exploited at a pro. Mcmoran copper and gold, was undertaken with the twin goals of characterizing the mineralogy and distribution of precious metals in the hypogene mineralization and developing insight into the possible reasons for the unusual metal endowments in this atypically for arizona aurich porphyry copper system. Supergene mineralisation of the boyongan porphyry copper. Mineralization is confined largely to eastwest and n 50 degrees eoriented shears and faults contained in a doubly plunging anticlinal dome of undifferentiated silurian and early devonian siltstones and shales. In ore deposit geology, supergene processes or enrichment are those that occur relatively near the surface as opposed to deep hypogene processes.
Online pharmacy no prescription price of viagra tablets. During early stages of alteration, the less resistant minerals chalcopyrite, sphalerite, and tetrahedrite if present 12. In my own collages viagra at anytime viagra use this link to protection adult diaper free just two fingers can may radiate to the. The alteration envelop around the goldbearing quartz veins shows lateral zoning comprising a silicified ferruginized and mylonitic zone sfz at. The gold distribution in humid environment shows au laterally spread in upper duricrust unit. Ferricrete genesis and supergene gold behaviour in burkina. If alunite is indeed primary, its presence provides important constraints on the chemistry of the ore fluid. The further comprehensive interpretation concern a process separating freshlypanned gold concentrate from residual mineral inclusions. Supergene processes include the predominance of meteoric water circulation with concomitant oxidation and chemical weathering. The sulphidic gold ore is hosted in intermediate to felsic intrusions that occur along the ns trending thrustfault zone within the socalled nabitah orogenic zone. Supergene ore and hypogene subeconomic gold mineralization. Veracruz,1, paul ashley,1 nancy vickery,1 and josh leigh2 1earth sciences, university of new england, new south wales, australia 2activex, brisbane, queensland, australia email, jose. Geology and geochemical aspects of lode gold mineralization.
Oxidation and secondary enrichment of gold deposits. Vancouver, british columbia marketwired july 24, 2014 indico resources ltd. The veins occur in steeply dipping brittleductile shear zones in a foliated biotite metagranite. Plateaus on a barren schist formation form the first two upper units. First, the enrichment may be primarily the result of the chemical removal of a large part of the gangue minerals, in which case the gold migrates slowly downward by gravity or is left behind as a residual. Supergene mineralization at the hydrothermal farbiste ore occurrence near poniky, central slovakia, was studied using optical and electron scanning microscopy, xray powder diffraction, electron microprobe and ir spectroscopy. To do this, i designed a broad, multidisciplinary research. Secondary and nanoparticulate gold from southern new zealand. In the magmatichydrothermal environment gold mineralization, if present, will be intimately associated with acidsulfate alteration, whereas in the nearsurface environment gold may occur in veins adjacent to or below acidsulfate alteration. Relationship between magmatism and mineralization in the rbm.
Idi is pleased to announce the maiden independent resource estimate for the supergene portion of the ocana porphyry coppergold project, southern peru. The gold deposits occur in or near regional transcurrent and oblique slipshear defor. The evolution of supergene enrichment in the morenci by. Based on the vein structures and textures, four stages of ore mineralization were developed consisting of a early stage. View gold mineralization research papers on academia. Boyle 1994 shows a similar sequence for sulfide replacement.
Given the lack of identified gold mineralization associated with jurassic intrusions in nevada, and the presence of carlintype mineralization in the southern part. Biogeochemical processes drive the transformation of gold au in surface environments. First upb laicpms in situ dating of supergene copper. The gandy gold base metal deposit is located in tertiary torudchahshirin volcanoplutonic range, north of central iran. Foland department of geological sciences, ohio state university, columbus, ohio 4321098 abstract. Mineralization at gandy occurs in close spatial relation with rhyolitic domes in a caldera setting in a. So, i decided to study supergene mineralization, because of its significant economic impact to the company and myriad of unanswered research questions. Oneil, department of geological sciences, university of michigan, ann arbor, michigan 481091063 and k. The dimakomboscorro lode gold deposit has two styles of mineralization. Supergene enrichment of a panafrican epithermal gold mineralization, journal of african earth sciences on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at.
The alteration envelop around the goldbearing quartz veins shows lateral zoning comprising a silicified ferruginized and mylonitic zone sfz. Supergene and surficial ore deposits, volume 3 1st edition. Supergene bornite, chalcocite, and rare covellite locally replace hypogene sulfides beneath the oxide zone. Conclusions this paper improves structural and lithological study of gold mineralization in the areas of bena and bakolobi. Within the afric zone, which carries an historic, non43101 compliant geological resource of 2. Original paper supergene mineralization of the medvedin. Supergene enrichment of a panafrican epithermal gold mineralization. A regional structural model for gold mineralization in the.
Boyongan is a blind copper gold porphyry deposit that was discovered by anglo american exploration philippines, inc. Indico has diamonddrilled a total of 9903 metres in 57 holes at the project. Porphyry deposits are the worlds principal resources of cu, mo, and re, and are major. The case of the booubyjan porphyry copper gold deposit, southeast queensland jose a. Supergene enrichment occurs at the base of the oxidized portion of an ore deposit. Drilling by prior operators encountered gold and copper mineralization over significant lengths in the subsurface. Sixteen common types of bedrock gold deposits are distinguished from one another and their main geological attributes are. Evidence for the supergene origin of alunite in sediment. The descending meteoric waters oxidize the primary sulfide ore minerals and redistribute the metallic ore elements. Supergene enrichment processes in porphyry systems. Gold and silver 178 distribution of supergene mineralization. Gold mineralization on the northshore property occurs in a number of settings. Indico announces maiden resource estimate of supergene. Supergene enrichment how natural processes have transformed lowgrade copper mineralization into economic ores by david f.
During early stages of alteration, the less resistant minerals chalcopyrite, sphalerite, and tetrahedrite if. A regional structural model for gold mineralization in the southern part of the archean superior province, united states by p. Supergene ore and hypogene nonore mineralization at the. Supergene mineralisation of the boyongan porphyry coppergold.