Geology and lodegold deposits of the nuka bay area, kenai peninsula, alaska by donald h. Lode gold occurs within the solid rock in which it was deposited. Most of the mines along the mother lode were hard rock gold mines, which means that the rock had to be crushed in order for the gold to be extracted. Hotz the klamath mountains geologic province, in northwestern california and southwestern oregon, is divisible into four northtrending concentric arcuate lithologic belts which are convex to the west. Research the geological properties of a particular goldbearing area of interest. He explains how orogenic gold formed during plate tectonic collisions and. Lode gold is known at several localities, but only two, barola reefs mine and. Archaean lode gold deposits in the coolgardie goldfield, western australia, occur in mafic and ultramafic rocks which have been metamorphosed to the amphibolite facies. The deposit type in this issue alone is referred to as synorogenic, turbiditehosted, mesothermal and archaean lodegold. Gold deposits are found in different types of rocks and geologic formations, falling into two mining categories.
Geology of the jamestown mine, mother lode gold district, ca. The faulting, folding and shearing that occurred in the mother lode belt has created zones of structurally weak rocks or contacts between different types of rock, which has been. In todays video i returned to the previous location to better examine the bed rock where i found a small amount of possible flour gold. The object of the survey was to map in detail the geology of an area covering the gold occurrences in the kainantu district, here called the kainantu goldfields, and to assess. Geology and structural controls of lodegold mineralization around the navachab gold mine in the panafrican damara belt of namibia. Gold geology and the natural indicators that can help you find gold. The current meaning ore vein dates from the 17th century, being an expansion of an earlier sense of a channel, watercourse in late middle english, which in turn is from the 11thcentury meaning of. Archean orogenic lode gold deposits are the result of large, complex mineralizing systems that have developed within many archean terrains. Crowe a comparison of australian and global examples. Dr richard goldfarb is a world expert on orogenic gold deposits.
Gold has historically been a key strategic commodity, and the study of gold deposit formation has long been investigated. During this trip, youll visit several famous mining towns of the mother lodecoloma, placerville. Feb 05, 2018 in todays video i returned to the previous location to better examine the bed rock where i found a small amount of possible flour gold. The explorer should be familiar in theory at least with the locality where he may expect to find valuable minerals. The alaskajuneau lode system for many years was one of the world s leading goldproducing areas. Geology and lodegold deposits of the nuka bay area, kenai peninsula, alaska professional paper 625 b by. Mesothermal lode gold deposit central belt peninsular. We have over 50 different gold books and gold maps that show where gold has been found in the past and provide instruction on gold prospecting methods.
In geology, a lode is a deposit of metalliferous ore that fills or is embedded in a fissure or crack in a rock formation or a vein of ore that is deposited or embedded between layers of rock. Several different structural styles are represented by the deposits of the coolgardie. The alaskajuneau lode system for many years was one of the world s leading gold producing areas. Lode deposits are contained within surrounding rock whereas placer deposits are dust particles contained in streams and. Geological surveys heavy metals program, describes the geology and lode. Gold in 2000 contents gold in 2000an introduction s. Gold deposits and their geological classification 911 metallurgist. Pdf geology and structural controls of lodegold mineralization.
A relatively rare element, gold is a precious metal that has been used for coinage, jewelry, and other arts throughout recorded history. The mother lode belt is an orogenic belt including a series of gold and mineral veins. The approximate total production of each lodegold mining centre, exclusive of byproduct gold, is also indicated on the map. Pdf the source of the ore fluid and hence of the gold in orogenic lode gold deposits remains unresolved. Economic geology unit, department of geology, university of buea, buea, south. I believe that most placers are fed by numerous small lode gold deposits that feed into. Like the gold deposits in nevada and colorado, epithermal mineralization in the canadian cordillera formed from the shallow circulation of meteoric water in subaerial, intermediate to felsic volcanic complexes. Most of the lodegold deposits in the tanami region are associated with d5 shear zones and fault systems.
The alteration envelop around the goldbearing quartz veins shows lateral zoning comprising a silicified ferruginized and mylonitic zone sfz. Conceptual mineral deposit model, archean lode gold deposits, greenstone belt. The faulting, folding and shearing that occurred in the mother lode belt has created zones of structurally weak rocks or contacts between different types of rock, which has been favorable for the deposition of gold bearing ores. Also, study the mineralization process of gold in general to determine which segment of a particular area may yield gold. The alteration envelop around the goldbearing quartz veins shows lateral zoning comprising a silicified ferruginized and mylonitic zone sfz at. Pdf documents opened from your browser may not display or print as intended. He explains how orogenic gold formed during plate tectonic collisions and especially during continental growth. Pdf numerous quartzvein hosted gold prospects in the karibib district in central namibia testify to the presence of a large hydrothermal. Gold is actually a relatively scarce element on the crust of the earth, but it occurs in trace quantities spread throughout many different kinds of rocks and in many different geological environments. Several different structural styles are represented by the deposits of the coolgardie goldfield. Guard introduction location and accessibility the sultan basin, as referred to in this report, is the part of. Like the gold deposits in nevada and colorado, epithermal mineralization in the canadian cordillera formed from the shallow circulation of meteoric water in. Groves key centre for strategic mineral deposits, department of geology and geophysics, the unit,ersity of western australia, nedlands, wa 6907, australia received 11 may 1995. Geology of the sepon copper and gold deposits, laos.
Natural gold indicators part 1 gold geology lesson. Mesoarchaean lode gold deposits despite contrasting fluidrock interaction histories. Total production from the years 1893 to 1946 has amounted to about 94 million dollars, with principal values in contained gold but with some silver and lead values. Geology and resources of gold in the united states 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. Geology of lode gold districts in the klamath mountains, california and oregon by preston e. Geology of lode gold districts in the klamath mountains. Lodegold mineralization in the tanami region, northern australia david l. Geology and ore deposits of the sultan basin, snohomish county, washington by w ard carithers and a. Gold also dissolves in alkaline solutions of cyanide, which are used in mining and electroplating. There are still places that contain gold that have never been worked, despite the fact that miners have been searching for gold for hundreds of years now. Sixteen common types of bedrock gold deposits are distinguished from one another and their main geological attributes are. Nov 10, 20 dr richard goldfarb is a world expert on orogenic gold deposits. Geology and ore deposits of the sultan basin, snohomish. Lode gold barola reefs mine mount victor gold prospect mount ubank prospect.
Learn about the geology of gold, equipment, techniques, basic prospecting and working a promising area. Geology of the sepon copper and gold deposits, laos bounoum bouttathep mmg limited, sepon district, savannakhet province, lao pdr. The mother lode belt is an orogenic belt including a series of gold and mineral veins found around its region. In bicentennial gold 88, extended abstracts oral programme. Introduction to geology and resources of gold, and. Not all gold deposits out there have been found and mined. Lode gold deposits are one of the most characteristic features of archaean greenstone belts within granitoidgreenstone terranes. 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. Lode gold geology of canadian mineral deposit types.
Debate on the genesis of socalled orogenic gold deposits 75% of gold recovered through history. Alluvial gold has been shed by the nasananka conglomerate, but far the greater proportion of the alluvial gold originated in the elendora porphyry. The dimakomboscorro lode gold deposit has two styles of mineral. One of largest silver lodes was the comstock lode in nevada, although it is overshadowed by the more recently discovered cannington lode in queensland, australia. Phillips, 20, continues largely because it is difficult to reliably identify the source of gold. The extractive metallurgy of gold gold deposits types. 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. Geological surveys heavy metals program, describes the geology and lode gold deposits of the area and attempts to evaluate its. The principal mine is the alaskajuneau mine, from which the lode system takes its name.
Geological and geographical characteristics of gold mines. Pdf fluid chemistry of lodegold deposits, and implications for. Prospecting for lode deposits begins with a search for mineralized outcrops, the key to the existence of which may often be found in mineralized float pieces of rock from the lode that have been loosened by weathering and washed downhill. Crowe a comparison of australian and global examples phanerozoic orogenic lode gold deposits f. The prospectors geology of lode gold and silver deposits, part 1. Shawe abstract gold has long been a store of wealth, whether held by governments or in private hoards. Geological features indicative of archean lode gold potential were extracted from the geoexploration datasets for use as inputs in the predictive model, based on the conceptual model for archean lode gold deposits. Lode gold deposits are present in all of the major tectonic subdivisions of the canadian landmass but occur dominantly in terranes with an abundance of volcanic and clastic sedimentary rocks of low to. Composition and origin of fluids associated with lode gold deposits. The largest gold lode in the united states was the homestake lode. Geology and origin of epigenetic lode gold deposits, tintina gold province, alaska and yukon. For instance, should he be searching for some heavy, detached substance that is usually found in placer deposits. Though scarce, gold is concentrated by geologic processes to form commercial deposits of two principal types. During this trip, youll visit several famous mining towns of the mother lodecoloma, placerville, jackson, angels camp, columbia, and.
Gold is relatively scarce in the earth, but it occurs in many different kinds of rocks and in many different geological environments. Geology and lodegold deposits of the nuka bay area, kenai. Lodegold mineralization in the tanami region, northern. The kennedy mine extracted gold from rock, usually quartz rock. Australia, brazil, canada, india, south africa, zimbabwe. Geology of the jamestown mine, mother lode gold district. On the source of orogenic gold geology geoscienceworld. May 05, 2017 77 gold prospecting tips how to find gold like a pro.
Geology and geochemical aspects of lode gold mineralization. An introduction to finding gold in stream and dry deposits. Lode gold deposits are one of the most characteristic features of archaean greenstone belts within granitoidgreenstone terranes, with major deposits situated in most major cratonic areas e. Data driven predictive modelling for archean lode gold. Mother lode fault california structural geology of. Dual origins of lode gold deposits in the canadian cordillera. Mineralisation was broadly synchronous with peak metamorphism, the main phase of granitoid emplacement, and regional deformation. Geology and structural controls of lode gold mineralization around the navachab gold mine in the panafrican damara belt of namibia thesis pdf available december 2011 with 528 reads how we. Research the geological properties of a particular gold bearing area of interest. The bed rock contains many quartz veins, along with small. Geologists now generally agree that most valuable mineral deposits have a magmatic origin and, therefore, that the most promising areas to prospect are in. Aof 158 source of lode and placer gold deposits of the.
Mesothermal lode gold deposit central belt peninsular malaysia 317 table 1 gives the malaysia s production of raw gold between 2006 and 2009, indicated over 90% of gold production is originated from pahang penjom gold mine since 1996, avocet mining plc, and recently from selinsing gold mine monument mining limited, and. These properties include the rock formations, structure, fault lines and the primary mineral content of the area. Geology and origin of epigenetic lode gold deposits, tintina gold. Rock and formations of the mother lode gold belt october. This report, a result of investigations under the u. Geology and lodegold deposits of the nuka bay area, kenai peninsula, alaska. Pdf geology and origin of epigenetic lode gold deposits. Lode gold deposits are one of the most characteristic features of archaean greenstone belts within granitoidgreenstone terranes, with major deposits situated in.
Mother lode gold belt of california internet archive. The dimakomboscorro lode gold deposit has two styles of mineralization. Mesothermal lode gold deposit central belt peninsular malaysia. Nov 01, 2006 the dimakomboscorro lode gold deposit has two styles of mineralization. The veins occur in steeply dipping brittleductile shear zones in a foliated biotite metagranite. Most of the economic gold deposits derive from porphyry gold deposited in the lake sediments and reworked by recent streams. Bayesian probability, weights of evidence, spatial association, mineral.
Download full paper as pdf for free until april 24, 2015. Regional geology premesozoic crystalline, sedimentary and volcanic rocks crop out in the maya mountains, a. Mineralizing systems are defined to include all geologic factors that control the generation and preservation of mineral deposits and emphasize the processes responsible for deposit formation at a variety of scales. Also available are gold pans in a variety of sizes and gold panning kits which include everything that you will need. A geological belt, or orogenic belt, forms when continental plates collide and crumple upwards to form mountains. Cassidy proterozoic lode gold and ironcoppergold deposits. The effort to understand the geology of gold was perhaps mans first serious effort at understanding the earths rocks and minerals. The remainder occurs in gold only deposits which comprise placers 5% and bedrock sources 60%, termed lode gold deposits e. When you understand the geology of the places where gold has already been found, you are more likely to spot the places where it might occur. Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction.
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