Richard J Goldfarb

China University of Geosciences (Beijing) · Department of Earth Science and Resources

The decrease in gold discoveries is affecting the deployment of new technology and the general society demand, demonstrating the need for new gold exploration approaches. To date, gold exploration remains primarily focused in areas near well-known large gold districts. We demonstrate the potential for new discoveries and significant resource expans...

Orogenic gold deposits are generally thought to represent one perhaps protracted event. However, recent research on orogenic gold deposits increasingly offers evidence for some deposits forming through multiple and clearly discreet hydrothermal episodes. The giant Zaozigou orogenic Au-Sb deposit in the Triassic to Cretaceous West Qinling Orogen, ce...

The San Albino deposit is an orogenic gold occurrence hosted by a low-angle thrust that is the site of a new open-pit mine in northern Nicaragua. The deposit is hosted in greenschist facies rocks of the Jurassic metasedimentary Neuvo Segovia Formation. The schist was uplifted and exposed during arc accretion and Cretaceous thin-skin deformation, fo...

The Jiangnan orogen, one of the largest gold-producing areas in China, has experienced multiple orogenic events with complex structural overprinting that is marked by multiple stages of magmatism, deformation, metamorphism, and orogenic gold mineralization. Different orogenic events have been recognized in the Neo-proterozoic, mid-Paleozoic, Triass...

Orogenic gold deposits account for more than 30 % of the global gold resources. To understand the genesis of orogenic gold deposits and ultimately target new orogenic gold deposits, it is important to determine the origin of gold. However, there has been a continuing debate surrounding gold source reservoirs. The Jiaodong gold province, comprising...

This study presents a low‐temperature thermochronological data set from the Jiaodong Peninsula in eastern China, including new zircon U‐Th/He and apatite fission‐track data from the Sulu Terrane in the eastern side of the Jiaodong Peninsula and published data from the Jiaobei Uplift to the west. These data reveal differential tectonic evolution bet...

Many workers accept a metamorphic model for orogenic gold ore formation, where a gold-bearing aqueous-carbonic fluid is an inherent product of devolatilization across the greenschist-amphibolite boundary with the majority of deposits formed within the seismogenic zone at depths of 6–12 km. Fertile oceanic rocks that source fluid and metal may be he...

Orogenic gold deposits are comprised of complex quartz vein arrays that form as a result of fluid flow along transcrustal fault zones in active orogenic belts. Mineral precipitation in these deposits occurs under variable pressure conditions, but a mechanism explaining how the pressure regimes evolve through time has not previously been proposed. H...

The Hunjiang basin in the northeastern North China block is host to a wide range of ore deposit types that are currently exploited by more than 100 past and producing mines. Extensive field and laboratory investigations were conducted to summarize the regional metallogeny, classify the different deposit types, and to place the deposits within a reg...

Eastern Cameroon hosts several gold districts. The Bétaré Oya and Colomine districts are underlain by greenstones and granitoid, respectively. Gold-bearing quartz veins occur cutting both lithologies, particularly along the Bétaré Oya Shear Zone and the Colomine Shear Zone. Deposits share similar features including structures, ore mineralogy, fluid...

The Klamath Mountains gold province is the second most important historical producer in California, having produced more than 7 Moz of gold from both lode and placer sources. Hydrothermal muscovite grains from gold-bearing veins provide the first ⁴⁰Ar/³⁹Ar age constraints indicative of a protracted period of mineralization in the Klamath Mountains....

The Bétaré Oya district has a substrate composed of the Neoproterozoic metavolcanic-metasedimentary rocks of the Lom Belt in eastern Cameroon. The district is well-known for alluvial gold mining activities, however, the primary gold mineralization has received little attention. In the current study, we newly report geological, ore mineralogy, fluid...

The Alto Guaporé gold province, southwestern Amazon craton, contains gold deposits that have been mined since the beginning of the 18th century and these deposits, together, have modern-day, pre-mining gold resources of at least 1.8 Moz. The ore is associated with quartz vein systems along the southeastern part of the Aguapei belt, a ~35 km wide an...

Effective exploration for ore deposits usually seeks distinct conditions within fundamentally prospective geological settings that might lead to enhanced ore–forming processes. Large–scale metal accumulation to form ore deposits is usually associated with specific tectonic events. Many studies have found that significant mineralization is genetical...

The origin of sediment-hosted copper-cobalt deposits (SCDs) within metamorphic terranes remains contentious, particularly in regard to the timing of mineralization relative to basin evolution. Here, we link the timing of Cu-Co mineralization in the Zhongtiao Mountains district, central China, to basin closure during development of the Trans-North C...

The Woumbou–Colomine–Kette district is located in the East Metallogenic Province of the Republic of Cameroon. Northeast- to E-striking splays of the regional Pan-African crustal-scale Sanaga Shear Zone control widespread gold mineralization. Gold occurs within local shear zones developed along granite-gneiss contacts, as well as within the margins...

Yanshanian (ca. 200–100 Ma) metallogeny of eastern Asia was dominantly controlled by oblique subduction and rollback of the Izanagi plate, and also, more locally in the north, by closure of the Mudanjiang Ocean basin and accretion of the Bureya-Jiamusi-Khanka block and the Sikhote-Alin terranes. Although exact distances are difficult to estimate du...

Porphyry-style mineralization is characterized by superposition of multiple generations of quartz growth, punc- tuated by dissolution and juxtaposed within a single vein. Such superposition inevitably obscures temporal re- lationships between quartz formation, alteration events, and fluid inclusion assemblages (FIAs), and consequently complicates t...

Epithermal, Carlin, and orogenic Au deposits form in diverse geologic settings and over a wide range of depths, where Au precipitates from hydrothermal fluids in response to various physical and chemical processes. The compositions of Au-bearing sulfidic hydrothermal solutions across all three deposit types, however, are broadly similar. In most ca...

The Jiaodong gold province, within the eastern margin of the North China block and the translated north- eastern edge of the South China block, has a stated premining gold resource exceeding 4,500 metric tons (t). It is thus one of the world’s largest gold provinces, with a present cumulative annual production estimated at 60 t Au. More than 90% of...

Muruntau in the Central Kyzylkum desert of the South Tien Shan, western Uzbekistan, with past production of ~3,000 metric tons (t) Au since 1967, present annual production of ~60 t Au, and large remaining resources, is the world’s largest epigenetic Au deposit. The host rocks are the mainly Cambrian-Ordovician siliciclastic flysch of the Besapan se...

Recent exploration has led to definition of a Middle–Late Jurassic copper belt with an extent of ~2000 km along the southeast China coast. The 171–153 Ma magmatic-hydrothermal copper systems consist of porphyry, skarn, and vein-style deposits. These systems developed along several northeast-trending transpressive fault zones formed at the margins o...

chap. H of Taylor, C.D., ed., Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II): U.S. Geological Survey Open-File Report 2013􏰀1280-H, 19 p

The Mustajärvi gold occurrence lies in the southern part of the Paleoproterozoic Central Lapland Greenstone Belt, in proximity to the first-order transcrustal Venejoki thrust fault system. The gold occurrence is structurally controlled by the second-order Mustajärvi shear zone, which is located at the contact between siliciclastic metasedimentary a...

China is a large country with a land area of approximately 9.6 million km2. It is a major producer of many commodities hosted within numerous mineral deposit types.

Understanding the relationship between mineral occurrences and host granitic rocks can be controversial. The Zaozigou Au-Sb deposit (118 t Au, 0.12 Mt Sb), hosted in metasedimentary rocks and dacitic to granodioritic sills and dikes, is one such example of a large gold deposit argued to have formed from either magmatic or metamorphic hydrothermal p...

Different types of primary or “lode” gold deposits possess unique patterns in space and time. Most such lode gold deposits formed from hydrothermal fluids in association with magmatic or metamorphic thermal events during times of continental growth. Granite-related gold deposits (porphyry, skarn, epithermal) formed in the upper 5 km of the crust fr...

China produces about 450 t Au per year and has government stated in-ground reserves of approximately 12,000 t Au. Orogenic gold, or gold deposits in metamorphic rocks, and associated placer deposits compose about 65 to 75% of this endowment, with lodes existing as structurally hosted vein and/or disseminated ore- bodies. The abundance of orogenic g...

The Barika deposit is the first documented auriferous Kuroko-type volcanogenic massive sulfide (VMS) deposit in Iran. It is hosted in meta andesites of the Sanandaj-Sirjan metamorphic Zone (SSZ). The mineralization and host rocks have been metamorphosed to lower greenschist facies. The deposit has Au and Ag grades in the stratiform lens averaging 3...

Assessing the structural evolution of the large Zaozigou gold-antimony deposit in the context of the tectonic evolution of the Triassic West Qinling orogen can resolve important gaps in our understanding of the deposit formation. Porphyritic ca. 250-215 Ma dacite intrusions intruded Triassic slates along existing planar features. Reaction skarns wi...

The Um Rus tonalite-granodiorite intrusion (∼6 km2) occurs at the eastern end of the Neoproterozoic, ENE-trending Wadi Mubarak shear belt in the Central Eastern Desert of Egypt. Gold-bearing quartz veins hosted by the Um Rus intrusion were mined intermittently, and initially by the ancient Egyptians and until the early 1900s. The relationship betwe...

The Arabian-Nubian Shield (ANS) is a rapidly emerging world-class province for gold resources mainly in structurally-controlled quartz ± carbonate veins that are best classified as late Neoproterozoic orogenic gold deposits. Gold has been mined in the Eastern Desert of Egypt, in the northwestern part of the ANS, for >6000 years, that is since the t...

Barika gold (and silver)-rich volcanogenic massive sulfide deposit is located 18 km east of Sardasht in the northwestern Sanandaj– Sirjan metamorphic zone. The rocks in the vicinity of the Barika deposit predominantly consist of Cretaceous volcano-sedimentary sequences of phyllite, slate, andesite, and tuffite, metamorphosed under greenschist facie...

China has been producing gold for more than 4,000 years and has been the world’s leading gold producer since 2009 yielding about 15% of the annual global production. The country produces 450 t Au per year and has government-stated in-ground reserves of approximately 12,000 t Au. At least 29 deposits have endowments of at least 100 t Au (table 1). C...

China produces about 450 t Au per year and has government stated in-ground reserves of approximately 12,000 t Au. Orogenic gold, or gold deposits in metamorphic rocks, and associated placer deposits compose about 65 to 75% of this endowment, with lodes existing as structurally hosted vein and/or disseminated orebodies. The abundance of orogenic gol...

The Hunjiang basin in Jilin Province, China, is host to a NE-trending sequence of sedimentary rocks located along the northeastern margin of the North China block in the Paleoproterozoic Jiao-Liao-Ji belt. The North China block is the largest and oldest cratonic block in China, but unlike other Precambrian cratons, its eastern part has been decrato...

With very few exceptions, orogenic gold deposits formed in subduction-related tectonic settings in accretionary to collisional orogenic belts from Archean to Tertiary times. Their genesis, including metal and fluid source, fluid pathways, depositional mechanisms, and timing relative to regional structural and metamorphic events, continues to be con...

The Willow Creek mining district was the third-largest lode gold district in Alaska in the 20th century, having produced 19 metric tons (t) of gold from vein deposits and another 2 t of gold from associated placer deposits. The district is located in the southern Talkeetna Mountains, north of the Castle Mountain strike-slip fault system. Most gold...

West Africa, with presently an approximate 10,000-metric ton (t) gold endowment, is one of the world’s great gold provinces and the largest Paleoproterozoic gold-producing region. The gold resources are concentrated within the 2250 to 2000 Ma greenstone belts of the Man-Leo shield, forming the southern part of the West Africa craton. Most of the ma...

West Africa, with an approximate 10,000-metric ton (t) gold endowment, is one of the world’s great gold provinces and the largest Paleoproterozoic gold-producing region. The gold resources are concentrated within the 2250 to 2000 Ma greenstone belts of the Man-Leo shield, forming the southern part of the West African craton. The gold endowment of t...

President Foster, fellow SEG members, and friends: It is a great privilege to introduce Steve Kesler for the 2015 SEG Marsden Award. This recognition is long overdue for Steve and, to be honest, I don’t know how we have let him slip through the cracks all these years. He should have received this award many years ago, as Steve has been an active vo...

The Jiaodong peninsula contains the most important concentration of gold deposits in China, which can be divided into Jiaojia-type and Linglong-type deposits based on mineralization style. The former is characterized by disseminated- and stockwork-style mineralization hosted in first-order regional faults, with relatively larger tonnages and lower...

Oligocene to Miocene post-collisional porphyry Cu deposits in the Gangdese belt in southern Tibet contain total resources of >20 Mt Cu and are genetically associated with granodioritic-quartz monzogranitic porphyry intrusions with adakite-like signatures (e.g., Sr/Y >40). The adakite-like magmatic rocks in the southern sub-belt of the eastern Gangd...

China is the world’s leading rare earth element (REE) producer and hosts a variety of deposit types. Carbon- atite-related REE deposits, the most significant deposit type, include two giant deposits presently being mined in China, Bayan Obo and Maoniuping, the first and third largest deposits of this type in the world, respectively. The carbonatite...

The NWW-striking North Qilian Orogenic Belt records the Paleozoic accretion–collision processes in NW China, and hosts Paleozoic Cu–Pb–Zn mineralization that was temporally and spatially related to the closure of the Paleo Qilian-Qinling Ocean. The Wangdian Cu deposit is located in the eastern part of the North Qilian Orogenic Belt, NW China. Coppe...

The Glojeh district contains silver- and base metal-rich epithermal veins and is one of the most highly mineralized locations in the Tarom-Hashtjin metallogenic province, northwestern Iran. It consists of four major epithermal veins, which are located in the South Glojeh and North Glojeh areas. Alteration in the Glojeh district consists of propylit...

The NNE-trending Linglong Metamorphic Core Complex hosts the majority of the gold deposits in the Jiaodong Peninsula of eastern China. Many of the deposits are hosted by the 163–155 Ma Linglong granite in the footwall of the Linglong detachment fault. Argon thermochronology suggests that the granite had cooled to 400 °C by 143 ± 1.5 Ma possibly as...

China is the world’s leading rare earth element (REE) producer and hosts a variety of deposit types. Carbonatite-related REE deposits, the most significant deposit type, include two giant deposits presently being mined in China, Bayan Obo and Maoniuping, the first and third largest deposits of this type in the world, respectively. The carbonatite-r...

The remote and rugged terrain of Alaska limits our ability to rapidly map the geology and determine the mineral potential of this vast state. Therefore, the USGS is conducting a pilot study using hyperspectral remote sensing data to map the regional mineralogy of exposures related to a broad range of mineral occurrences. The use of remotely sensed...

It is quite evident that it is not anomalous metal transport, nor unique depositional conditions, nor any single factor at the deposit scale, that dictates whether a mineral deposit becomes a giant or not. A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral...

Orogenic gold deposits of all ages, from Paleoarchean to Tertiary, show consistency in chemical composition. They are the products of aqueous-carbonic fluids, with typically 5–20 mol% CO2, although unmixing during extreme pressure fluctuation can lead to entrapment of much more CO2-rich fluid inclusions in some cases. Ore fluids are typically chara...

The Grass Valley orogenic gold district in the Sierra Nevada foothills province, central California, the largest historic gold producer of the North American Cordillera, comprises both steeply dipping E-W veins located along lithologic contacts in accreted ca. 300 and 200 Ma oceanic rocks and shallowly dipping N-S veins hosted by the Grass Valley g...

The Qolqoleh orogenic gold deposit in the northern part of the Sanandaj–Sirjan metamorphic belt in northwestern Iran is hosted by a steeply dipping sequence of greenschist facies Cretaceous volcano–sedimentary rocks, including mafic to intermediate metavolcanic rocks, sericite and chlorite schist, and marble. Geochemical and petrochemical data incl...