Geochemistry, alteration, and genesis of gold mineralization in the okote area, southern ethiopia debele j. The term mesothermal veins is really a sack term, referring simply to the depth formation. They are the most numerous of all classes of deposit. Although finding an attractive prospect in the first place is hard work, a majority of exploration budgets these days is spent on assessment. Au is regularly distributed in the weathering profile at the. Sawyerkeystone trend of auagas deposits in randolph. Varying mechanisms of mineraldeposition are apparent within multi epithermal and porphyry gold geological models by dr greg corbett figure 1. Also termed as greenstone hosted gold deposits, orogenic gold deposits, shear gold deposits, goldonly deposits intrusion related deposits deposits having spatial and genetic relationship with. Pdf epithermal gold deposits styles characteristics an.
Stage i, which is related to ductile, sinistral oblique slip fault movement and stage ii, which is related to brittleductile and brittle strikeslip fault movement. Geology and geochemistry of epithermal systems presents a synthesis of the current under standing of the processes responsible for the concentration of metals especially gold and silver in nearsurface environments, provides an overview of the systematics of the most important approaches to. Lithotectonic classification of gold deposits lode gold deposits epigenetic vein deposits of gold in metamorphic terranes kerrich, 1993. The majority of proposed mining projects involve the extraction of ore deposits such as copper, nickel, cobalt, gold, silver, lead, zinc, molybdenum, and platinum. The mine is capable of producing 325,800 tons of highgrade ore per year for 8 years.
Overview of mining and its impacts1 proposed mining projects vary according to the type of metals or materials to be extracted from the earth. Mesothermal veins are known for their large size and continuation to depth, and therefore, are a major source of the world. These deposits can be very desirable to mining and exploration companies, and its. The auas and ausb associations are common in gold deposit. The country remains underexplored to discover new deposits as well as realising full potential of known deposits. Hydrothermal mineral deposits are those in which hot water serves as a concentrating, transporting, and depositing agent. Page 1 nc geological survey publications list available at our online store click on it for link updated april, 2018 by medina. Epithermal deposits typically form above the level of porphyry cuau deposits figure 4.
Pueblo viejo highsulfidation epithermal goldsilver deposit. Pueblo viejo highsulfidation epithermal goldsilver deposit, dominican republic. There are six worldclass settings for magmatichydrothermal gold deposits. A new model of formation beneath barren limestone cover a reply richard h. A human resources strategy for mine development projects by sriram ram sampathkumar ms, computer engineering kiev international university of civil aviation, 1995 project submitted in partial fulfillment of the requirements for the degree of master of business administration in the executive mba program of. Epithermal gold for explorationists paper 200201, april 2002 5 mineralogical differences used to categorise the styles of low sulphidation epithermal gold deposit styles corbett and leach, 1998. Mineral deposit mineral deposit hydrothermal solution. They are popular with prospectors because can yield very rich deposits and they are widespread in the western us. Geology and geochemistry ofthe golden butte mine a small carlin. In the laterite of the dondo mobi gold deposit dis trict of eteke, south gabon, the evolution of au distri bution is not the same for all grainsize fractions.
Hydrothermal fluids forming epithermal gold deposits are ausaturated in most cases, whereas deposits of. Files available from the acs website may be downloaded for personal use only. Pdf geophysical exploration for epithermal gold deposits. This report titled asanko gold mine definitive feasibility study. Distinctive features typically present include key alteration mineral assemblages low sulphidation.
Box 28503, addis ababa, ethiopia 2department of geological sciences, university of vienna, althanstrasse 14, a1090 vienna, austria received december 31, 2003. Mesothermal and greenstone gold deposits aka orogenic geology formation. Boiling is the process that most favors precipitation of bisulfidecomplexed metals such as gold. More information about viewing, downloading, and printing report files can be found here. The miocene wafigolpu gold rich porphyry cuau deposit, and associated epithermal au mineralisation is located in the morobe province of png, and has a currently published resource of 28. Hydrothermal deposits are never formed from pure water, because pure water is a poor solvent of most ore minerals. This is a pdf file of an unedited manuscript that has been accepted for publication. At new celebration, gold mineralization took place in two stages. The two industries ranked together as the primary or basic industries of early civilization. Canadian au production from epithermal deposits has been minor deposits, or to other lode au deposits. Jeffrey hedenquist university of ottawa 115 publications 4,022 citations see profile noel c. This process and the concomitant rapid cooling also result in many related features, such as ganguemineral deposition of quartz with a colloform texture, adularia and bladed calcite in lowsulfidation deposits. Remaining inground gold resources in the province are estimated at 280 million ounces. The first is epithermal gold deposits associated with magmatic rocks, the second is epithermal gold deposits associated with sedimentary rocks carlintype and the third is epithermal gold.
Pdf documents opened from your browser may not display or print as intended. Sedimenthosted copper deposits ssc characterized by a prominent copperrich zone in a red and grey bed sedimentary sequence. Gold in 2000 contents gold in 2000an introduction s. All these must be captured in even a small scale gold mining business proposal. Pete sainsbury l introduction the writer first began geologic studies on the seward peninsula in 1952. Definitely, location and size of the operation will determine how a miner will start a gold mine. Introduction to geology and resources of gold, and geochemistry of gold the case for gold an introduction to geology and resources of gold in the united states by daniel r. Introduction to geology and resources of gold, and. Most of the small placer gold deposits in existence today are the result of reworking this glacial debris. Like those with yellowstone in wyoming or rotorua in new zealand.
The high and low sulphidation epithermal deposits associated with blue coloured belts are late mesozoic and cenozoic in age generally nov 02, 2014 ore deposit is a natural concentration of one or more minerals within the host rock. Orogenictype coppergoldarsenicbismuth mineralization at. The geological and grade continuity of the pajingo epithermal. Scribd is the worlds largest social reading and publishing site. Here is a sample business plan for starting a gold mining company. The lower section of caroni river bajo caroni, has been a known producer of gold and diamonds for over thirty years. This photo is pamukkale, low sulfidation hot springs in turkey, with a beautiful white centre terraces. Mesothermal vein gold deposits inn investing news network. Although these deposits form in distinctly different geologic settings and by. Goldoxysulphides in copper deposits of the greywacke zone, austria. Miocene and early pliocene epithermal goldsilver deposits in.
Cassidy proterozoic lode gold and ironcoppergold deposits. Geology, ore deposits, and mineral potential of the seward peninsula, alaska by c. Mineral deposits of nevada society of economic geologists. Jasperoid is commonly brecciated, and vugsand veins indicate. Well they are a major source of gold, providing about 12% of the worlds annual gold production, in fact they are the second largest producers of gold globally after the witwatersrand deposits. Shawe geochemistry of gold in hydrothermal deposits by samuel b. Hydrothermal gold deposits epithermal, carlintype, and orogenic have accounted for 75% of lode gold production. Prices of reports released to the open files are given in the listing u. Gold behavior in weathering products of quartz vein in. Metallurgical testwork on 76 samples of all material types returned over 90% recovery. Technical report and mineral resource and reserve update. Nevada is known as the silver state, due primarily to the early pre1860 silver production from the comstock lode in the virginia city area. The deposit occurs within the pajingo epithermal system pes, 72km south of charters towers in northeast queensland, australia porter 1990.
Recreational gold panning pdf wisconsin dnr wisconsin. Characteristics of highsulfidation epithermal deposits, and their relation to magmatic fluid antonio arribas jr. Gold deposits can still be seen today forming in some active geothermal areas. Download the latest version of adobe reader, free of charge. Jul 12, 20 epithermal gold deposits are among the richest gold deposits in the world with some bonanza grade ore shoots containing more than gt gold, or in other words, a kilogram of gold for every tonne of rock mined. Mineral resources department, geological survey of japan, 1 higashi, tsukuba 305, japan introduction a consequence of the increased exploration for gold deposits during the late 1970s and early. Gold prospecting with a vlf metal detector by dave johnson, first texas 10 mar 2010 edition, 2. Geophysical exploration for epithermal gold deposits. Pueblo viejo highsulfidation epithermal goldsilver. Hydrothermal fluids forming epithermal gold deposits are ausaturated in most cases, whereas deposits of carlintype are auundersaturated. Mesothermal and greenstone gold deposits aka orogenic geology. Ore deposit is a natural concentration of one or more minerals within the host rock. Namibia, 12 2000, 169177 mineralogy of the navachab skarn deposit, namibia.
Epithermal gold and silver in newfoundland and labrador. Magmatichydrothermal origin of mercury in carlinstyle and. This is a pdf file of an unedited manuscript that has been accepted. Diagnostic features of epithermal gold deposits geological, mineralogical, and geochemical features of epithermal au deposits are listed for each of three deposit subtypes in table 2. Epithermal deposits form in the ground at shallow depths. Styles, characteristics, and exploration book march 1996 citations 9 reads 40 4 authors, including. Geochemistry, alteration, and genesis of gold mineralization. Also termed as greenstone hosted gold deposits, orogenic gold deposits, shear gold deposits, goldonly deposits intrusion related deposits deposits having spatial and genetic relationship with igneous intrusions. Other articles where epithermal deposit is discussed. Read on for a brief overview of epithermal gold deposits, from how they form to what the different types are. Epithermal gold deposits styles characteristics an.
Wau quartz veins located around the mine granite small granitic plug. It has subsequently been refined withfluid inclusion data to indicate that epithermal ores form over the temperature range of 150 o c to 300 o c, from the surface to as deep as 1 to 2 km. This compilation on mineral deposits from society of economic. Gold mining operations range from tiny to gigantic.
Crowe a comparison of australian and global examples phanerozoic orogenic lode gold deposits f. White university of tasmania 58 publications 1,080 citations. Geology is a science of general tendencies with frequent exceptions, not one of hard and fast rules that are always true and never vary. Left click on the picture to obtain a more readable pdf file of the gold fields and gold occurrences map of wa that you can print how do you find goldfields and old gold mines in western australia. Smith2 abstract mines in the oatman mineralized district, near oatman in northwestern arizona, have produced more than 1.
Epithermal veins tend not to have great vertical continuity, but many are exceedingly rich and deserving of the term bonanza. This conclusion was initially based on geologic reconstructions, ore mineralogy and related textures lindgren, 1933. Geological survey openfile reports, updated month ly, which is for sale in microfiche. Its important to know not only where the goldfields and old gold mines are in wa but also what sort of mining is or was undertaken there for example was the historical gold mining. Unfortunately, the tonnage of ore in epithermal veins is typically small compared with other types of lower grade gold deposits. Recognising sinters in epithermal gold deposits surficial deposits of siliceous sinter are a com mon feature of presentday hot springs in areas of active volcanism, but they are rarely recognised in older, eroded volcanic ter ranes because of their low preservation poten tial, and their limited vertical and lateral.
Sedimenthosted gold deposits of the worlddatabase and grade. Conceptual model illustrating the styles of pacific rim porphyry to epithermal cu. Gold deposits in polydeformed metasedimentary rocks. Gold mineralization is found in all alteration types, but jasperoid is the most important host for ore. Abdel latifs close ties to the security services and. 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. A fascinating group and characteristic of epithermal gold deposits is that you can virtually see them forming today, simply by visiting hot springs. As a service to our customers we are providing this early. Epithermal gold deposits part ii geology and gold deposits of the oatman district, northwestern arizona by ed dewitt, jon p.
Epithermal gold and silver deposits icmjs prospecting. More than 90% of gold deposits in zimbabwe are associated with greenstone belts which are some of the richest and comparable to those. Although, the mineralization at sabodala has drawn the attention of some workers sylla and ngom 11, gueye et al. What are the characteristic textures of epithermal gold deposits.
Just starting out with the hobby of amateur gold prospecting and want to know where to find gold deposits. The aim of this project was to define the geological and grade continuity of the vera south gold deposit, and to use this knowledge to apply geostatistical resource estimation techniques to the deposit. One of the largest undeveloped gold projects in the world. Mesothermal and greenstone gold deposits aka orogenic. Before you get out into the field to try your hand at gold panning or metal detecting, its worth taking a moment to learn about the different types of gold deposits. The shallow origin of epithermal au deposits makes them more susceptible to erosion, and, accordingly, epithermal au deposits have represented a highgrade, readily mineable. Gold tends to be concentrated in the vapor phase of fluids at high temperatures and pressures. Epithermal gold deposits are among the richest gold deposits in the world with some bonanza grade ore shoots containing more than gt gold, or in other words, a kilogram of gold for every tonne of rock mined. Mining laws and regulations, changes and revisions circular 104, august, 2003, revised july, 2014 rev. Sillitoe, 27 west hill park, highgate village, london n6 6nd, england david j. A feasibility study on the production of gold at a fictitious mine moapa mine in elko county, nevada is to be performed. Technical report and mineral resource and reserve update for the nzema gold mine, ghana, west africa page iii nzema mine april 2, 20 at aliva and the mineralization in other deposits in this area are nonrefractory. Mich geological survey, open file report, prepared in cooperation with michigan college of mining and.