Table of Contents
- Introduction
- Interior Alaska and the Geographic Limits of the Yukon–Tanana Province
- Tectonic Development of the Yukon–Tanana Terrane
- Metamorphic Rocks, Intrusive Suites, and Structural Architecture
- Gold Metallogeny of the Tintina Gold Province
- Fairbanks Mining District: Lode Systems and Placer Sources
- Goodpaster Mining District and the Pogo Gold Deposit
- Fortymile, Circle, and Eagle Placer Districts
- Richardson and Big Delta Gold Mineralization
- Livengood and the Tolovana Placer District
- Lode-Gold Deposit Models in Interior Alaska
- Placer Formation, Buried Channels, Bench Gravels, and Permafrost
- Geological Prospecting Methods and Their Limitations
- Conclusion
- Related Reading
- References
1. Introduction
Interior Alaska contains a broad and geologically varied group of placer districts, lode-gold systems, intrusive complexes, metamorphic belts, and major fault zones extending through the drainage basins of the Yukon and Tanana Rivers. Much of its historic gold production came from districts developed across the Yukon–Tanana Upland, including Fairbanks, Fortymile, Circle, Eagle, Richardson, Goodpaster, Livengood, and Tolovana. These districts share a regional tectonic setting, but they do not contain one uniform type of gold deposit. Their mineralization includes intrusion-related vein and stockwork systems, structurally controlled quartz bodies, disseminated deposits, polymetallic veins, skarn-related occurrences, and placers derived from one or several bedrock sources.
The term Yukon–Tanana Province is useful geographically, but the geological literature more commonly distinguishes the Yukon–Tanana Upland from the tectonically defined Yukon–Tanana terrane. The upland is a physiographic region, whereas the terrane consists of multiple metamorphosed sedimentary, volcanic, and intrusive assemblages assembled through a prolonged history of continental-margin development, ocean-basin formation, subduction, deformation, metamorphism, intrusion, and fault displacement. The two terms overlap spatially but are not interchangeable.
This distinction is necessary when interpreting gold distribution. A placer creek may cross several rock units and collect gold released from more than one mineralized structure. A lode deposit, by contrast, must be evaluated according to its specific host rock, mineral assemblage, alteration, structure, intrusive association, and age. Regional similarities can guide investigation, but district-specific evidence must determine geological interpretation. [1][2][3]
2. Interior Alaska and the Geographic Limits of the Yukon–Tanana Province
Interior Alaska is a geographic term applied broadly to the continental part of Alaska lying north of the Alaska Range and south of the Brooks Range. It includes the extensive valleys and uplands drained by the Yukon River, Tanana River, Koyukuk River, and their tributaries, but it crosses several distinct geological provinces. The Yukon–Tanana Upland is more restricted. It extends across east-central Alaska between the Yukon River on the north and the Tanana River lowland on the south and continues eastward toward Yukon, Canada. Rounded ridges, broad valleys, discontinuous permafrost, loess-covered slopes, and deeply weathered uplands characterize much of the region. These surficial conditions conceal bedrock over large areas and complicate direct geological mapping and mineral exploration. The underlying Yukon–Tanana terrane consists principally of metamorphosed sedimentary, volcanic, and intrusive rocks, but its mapped boundaries do not follow the physiographic limits of the upland exactly. Older reports frequently grouped broad areas of metamorphic rock under the name Birch Creek Schist. Modern mapping has divided those rocks into several assemblages based on protolith, metamorphic grade, structural position, geochemistry, and isotopic age. Historical reports remain important for mine descriptions and placer records, but their generalized stratigraphic terminology should not be transferred directly into modern geological interpretation. The principal gold districts also occupy different parts of the regional framework. Fairbanks lies in the western Yukon–Tanana Upland, Fortymile and Eagle occupy the eastern border region, Circle lies along the northern part of the upland, and Goodpaster and Richardson occur nearer its southern margin. Livengood is northwest of Fairbanks near major terrane boundaries and regional fault systems. Their inclusion within Interior Alaska does not establish identical host rocks, mineralizing ages, or deposit models. [1][2][4]
3. Tectonic Development of the Yukon–Tanana Terrane
The Yukon–Tanana terrane is a composite tectonic assemblage rather than a single continuous formation. Its rocks preserve evidence of Paleozoic sedimentation, continental-margin and volcanic-arc magmatism, ocean-basin development, subduction, metamorphism, structural stacking, and later intrusion. Metasedimentary units include rocks derived from sandstone, shale, carbonate sediment, and related continental-margin deposits. Metavolcanic and metaigneous units record multiple episodes of felsic and mafic magmatism. These rocks were later deformed and metamorphosed under conditions ranging from lower-grade greenschist facies to amphibolite facies, with localized high-pressure assemblages documenting deep tectonic burial. Differences in metamorphic grade and protolith across short distances indicate that separate crustal packages were placed together along faults and ductile shear zones. Fault-bounded rocks assigned to the Seventymile terrane contain oceanic and ultramafic components generally interpreted as remnants of a late Paleozoic to early Mesozoic ocean basin. Their present position against Yukon–Tanana rocks records tectonic closure and structural emplacement, although the timing and geometry of individual contacts remain subjects of continuing mapping and revision. Mesozoic deformation was followed or accompanied by repeated emplacement of granitic and intermediate plutons. Later brittle faults and major strike-slip systems displaced, exposed, and locally reactivated older structures. This succession created favorable conditions for hydrothermal mineralization by producing heat sources, fractured host rocks, chemically reactive contacts, and long-lived pathways for fluid movement. It does not follow, however, that every fault or pluton is mineralized. Some gold systems formed near particular intrusive suites, while others were controlled primarily by structures that may have existed before mineralization and were reopened during later tectonic events. The available evidence supports several mineralizing episodes across the province rather than one event responsible for all Interior Alaska gold. [2][5][6]
4. Metamorphic Rocks, Intrusive Suites, and Structural Architecture
Bedrock within the Yukon–Tanana region includes quartzite, quartz-mica schist, pelitic schist, amphibolite, gneiss, marble, calc-silicate rock, metagranitic rock, and metamorphosed volcanic units. These lithologies differ in strength, fracture behavior, permeability, and chemical reactivity. Competent quartz-rich rocks may develop persistent brittle fractures, while micaceous schists may deform along foliation or preexisting shear fabrics. Carbonate-bearing rocks can react strongly with hydrothermal fluids and may develop skarn, replacement bodies, or calc-silicate alteration near suitable intrusions. Amphibolite and graphitic or sulfidic metasedimentary rocks can also influence fluid chemistry and structural localization, but their presence alone does not demonstrate gold mineralization. The region was intruded during several periods by granite, granodiorite, tonalite, diorite, monzonitic bodies, and numerous dikes. Some Cretaceous and Paleogene intrusive complexes are spatially and temporally associated with important gold deposits, including systems in the Fairbanks, Goodpaster, and Livengood districts. Other intrusions show little known gold mineralization. A genetic connection between an intrusion and a deposit requires more than geographic proximity. Crosscutting relationships must establish relative timing, and stronger interpretations may rely on radiometric ages, alteration zoning, mineral chemistry, fluid-inclusion evidence, isotopic data, and systematic metal associations. Structure is equally important. Regional thrust faults, ductile shear zones, high-angle faults, fold hinges, intrusive contacts, and later fracture networks created pathways in which hydrothermal fluids could circulate and precipitate minerals. Some structures were reactivated repeatedly, meaning that veins of different ages or compositions may occupy the same general corridor. Later movement may offset, crush, or remobilize earlier mineralization. Consequently, a mapped fault should be treated as a potential fluid pathway requiring investigation, not as evidence of an orebody. The geological significance of any structure depends on its age, orientation, displacement history, alteration, mineral content, and relationship to surrounding rock units. [3][4][7]
5. Gold Metallogeny of the Tintina Gold Province
Much of Interior Alaska lies within the Tintina Gold Province, a broad metallogenic belt extending from southwestern Alaska through east-central Alaska and into Yukon. The province contains large lode deposits, numerous prospects, and major placer districts associated with regional magmatism, deformation, fault development, uplift, and erosion. The term identifies a regional concentration of gold systems; it does not define one deposit type. Important mineralizing events occurred during the Cretaceous and Paleogene, when granitic magmas and hydrothermal systems developed across large parts of the northern Cordillera. Major fault systems, including the Tintina fault, influenced crustal architecture, sedimentary-basin development, intrusive emplacement, and later displacement. Subsidiary structures also localized hydrothermal alteration and veins. Many Interior Alaska gold occurrences contain combinations of arsenopyrite, pyrite, stibnite, scheelite, bismuth-bearing minerals, tellurium-bearing minerals, and base-metal sulfides. These minerals can serve as geological or geochemical indicators, but their significance is deposit-specific. Tungsten and bismuth associations are prominent in parts of the Fairbanks district, while arsenic and antimony occur in several districts and are not unique to one deposit model. The Tintina province includes deposits interpreted as reduced intrusion-related gold systems, structurally controlled high-grade quartz systems, disseminated deposits, and polymetallic veins. Some occurrences classified historically as gold prospects contain primarily silver, lead, zinc, copper, tungsten, or antimony and should not be represented as major gold deposits without supporting production or resource data. The province’s regional endowment reflects repeated geological processes acting on a favorable crustal framework, but mineralization remains unevenly distributed. Extensive areas between known districts contain little exposed evidence because they may be barren, poorly mapped, deeply weathered, or concealed beneath loess, colluvium, alluvium, vegetation, and permafrost. Regional prospectivity therefore represents a basis for investigation, not proof of undiscovered economic mineralization. [3][8][9]
6. Fairbanks Mining District: Lode Systems and Placer Sources
The Fairbanks mining district is one of the best documented examples in Interior Alaska of a major placer field occurring downstream from multiple bedrock-gold systems. The district is underlain principally by metamorphic rocks of the western Yukon–Tanana terrane, including quartz-rich schist, mica schist, amphibolite, calc-silicate rock, marble, and higher-pressure metamorphic assemblages. These rocks are cut by granitic plutons, dikes, faults, shear zones, and quartz-vein systems. Important lode areas occur around Cleary Summit, Pedro Dome, Ester Dome, and adjoining ridges. Mineralization includes discrete quartz veins, shear-controlled veins, sheeted vein arrays, stockworks, disseminated gold, and intrusion-hosted systems. Associated minerals locally include arsenopyrite, pyrite, stibnite, scheelite, bismuth minerals, tellurides, and base-metal sulfides. The combination of Cretaceous intrusive activity, gold-bearing quartz systems, and characteristic bismuth-tungsten-antimony-tellurium associations has led many researchers to interpret substantial parts of the district as a reduced intrusion-related gold system. That interpretation is well supported for several deposits but should not be applied automatically to every vein in the district. The Fort Knox deposit is a large, relatively low-grade system hosted principally by granitic rock containing quartz and quartz-sulfide vein networks. Historic placers developed in Cleary Creek, Pedro Creek, Goldstream Creek, Ester Creek, Dome Creek, and associated tributaries. Some pay channels were buried beneath younger alluvium, colluvium, loess, and frozen organic-rich silt, requiring shafts, underground drifting, thawing, dredging, or mechanical stripping. Their gold was not distributed uniformly. Bedrock source location, stream migration, channel gradient, bench formation, sediment reworking, bedrock irregularities, and repeated mining all affected the position and preservation of pay streaks. The district proves that productive lodes and placers can occur within the same regional system, but it does not establish that every nearby drainage or quartz vein contains significant gold. [4][7][10][11]
7. Goodpaster Mining District and the Pogo Gold Deposit
The Goodpaster mining district contains the Pogo gold deposit, a high-grade lode system hosted by metamorphic rocks of the Yukon–Tanana terrane near the Goodpaster batholith. The principal ore zones include tabular to gently dipping quartz bodies historically identified as the Liese zones, together with additional mineralized structures defined during exploration and mine development. Gold occurs in quartz veins and replacement-style bodies containing relatively small quantities of arsenopyrite, pyrite, pyrrhotite, and bismuth-bearing minerals. Alteration includes variable combinations of biotite, sericite, carbonate, albite, and quartz. Geological evidence supports a Cretaceous hydrothermal event associated spatially and temporally with regional magmatism, but the deposit’s genetic classification has remained debated. Pogo has characteristics of structurally controlled orogenic gold deposits, including high-grade quartz bodies localized by deformation, while its intrusive association and metal assemblage support comparison with intrusion-related gold systems. The most defensible interpretation is therefore based on its observed structural, mineralogical, and chronological features rather than forcing it into a single idealized model. Pogo also demonstrates that major Interior Alaska lodes may possess limited surface exposure beneath vegetation, soil, colluvium, and discontinuous permafrost. Geochemical studies detected natural variations in metals and other elements around mineralized ground, but no single soil, stream-sediment, water, or vegetation anomaly reliably identifies an orebody. Meaningful exploration requires agreement among mapped structures, host rocks, alteration, geochemistry, geophysics, and drilling. The discovery of Pogo establishes that concealed high-grade mineralization occurs in the Goodpaster district; it does not establish that every arsenic or gold anomaly in the district represents a deposit of comparable size or grade. [9][12][13]
8. Fortymile, Circle, and Eagle Placer Districts
The Fortymile, Circle, and Eagle districts contain some of Interior Alaska’s oldest and most extensively worked placer fields. Gold was discovered in the Fortymile region in 1886, and the USGS estimated approximately 500,000 troy ounces of recorded regional placer production through the period evaluated in its 1996 study. That historical estimate is not a statement of present reserves or recoverable gold. Fortymile placers occur in active channels, tributaries, abandoned channels, high terraces, and bench gravels produced by repeated stream incision and landscape change. Gold may have been eroded from numerous small veins, altered intrusive rocks, shear zones, or mineralized contacts rather than from one large exposed lode. Older auriferous gravels were locally dissected and their gold reconcentrated in younger channels. The Circle district, including streams such as Mastodon Creek and Deadwood Creek, and the Eagle-area placers developed within related regional bedrock but possess distinct drainage histories and source relationships. Their geological similarity does not justify treating the three districts as one deposit. Some productive gravels were concealed beneath frozen silt, younger alluvium, colluvium, or terrace deposits and were worked historically through shafts and underground drifts. A gravel bench above a present stream is not inherently gold-bearing; it must represent a former channel that received auriferous sediment and preserved a hydraulically concentrated layer. Likewise, placer gold in a modern creek may have been reworked through several older deposits before reaching its present position. Prospecting interpretation must therefore distinguish present stream sediment from buried paleochannels, terrace remnants, colluvial material, and previously mined or redistributed gravel. [14][15][16]
9. Richardson and Big Delta Gold Mineralization
The Richardson mining district and adjoining Big Delta region contain placer deposits and lode prospects within metasedimentary and metaigneous rocks intruded by several generations of plutons and dikes. Gold mineralization occurs in quartz veins, breccias, stockworks, altered intrusive rocks, and fault-controlled zones. Early work emphasized the Richardson lineament as a possible regional control, but modern mapping recognizes a more complicated network of faults, shear zones, folds, and reactivated structural corridors. The Black Mountain tectonic zone east of Richardson contains northeast-trending faults, intrusions, brecciation, alteration, and numerous mineral occurrences. These observations support the conclusion that long-lived structures provided pathways for hydrothermal fluids, although they do not prove that all mineralization within the corridor formed during one event. Mineral occurrences contain variable combinations of gold, silver, arsenic, antimony, bismuth, tungsten, copper, lead, and zinc. Where base metals or silver dominate, the occurrence should not be represented as a major gold deposit. Placer mining developed in Tenderfoot Creek and nearby drainages, but the sources of all placer concentrations have not been tied conclusively to individual exposed lodes. Thick loess, alluvium, vegetation, weathered bedrock, and permafrost restrict exposure, allowing mineralized structures to remain concealed while also making surface anomalies difficult to interpret. DGGS mapping and analytical programs have therefore concentrated on bedrock correlations, intrusive ages, fault relationships, geochemistry, and geophysics. The evidence supports further geological investigation of covered structural targets, but it does not support assuming that every fault below a placer drainage contains economic mineralization. [17][18][19][20]
10. Livengood and the Tolovana Placer District
The Livengood–Tolovana district, northwest of Fairbanks, contains historic placer deposits and a large disseminated bedrock-gold system within a structurally complex assemblage of sedimentary, volcanic, ultramafic, intrusive, and altered rocks. Placer mining developed in Livengood Creek, Ruth Creek, Amy Creek, and related drainages after the 1914 discovery. Earlier USGS studies documented small lode occurrences in siliceous sedimentary rocks, altered breccias, and silica-carbonate rocks near monzonitic stocks and dikes. Those occurrences demonstrated plausible local bedrock sources but did not explain every part of the placer field. Later exploration identified broad gold mineralization associated with faults, brecciation, dikes, and hydrothermal alteration. Arsenopyrite and stibnite are important locally, but neither mineral alone defines ore. The deposit has commonly been interpreted as intrusion-related or intrusion-influenced, although structural preparation played a major role in controlling fluid movement and mineral distribution. The historic placers and the recognized bedrock system occur within the same district, but it has not been demonstrated that all placer particles came exclusively from the presently defined deposit. Several mineralized structures may have contributed gold, and older auriferous sediment could have been eroded and reconcentrated repeatedly. Livengood illustrates that a large source can be disseminated and partly concealed rather than expressed as one prominent quartz vein. It also illustrates the limits of placer evidence: a rich downstream concentration confirms an auriferous sediment source but does not establish the grade, tonnage, geometry, or exact position of a lode. Those properties require bedrock sampling and drilling. [21][22][23]
11. Lode-Gold Deposit Models in Interior Alaska
Interior Alaska lodes are commonly evaluated using reduced intrusion-related, orogenic, disseminated, skarn, and polymetallic vein models. Reduced intrusion-related systems occur near felsic to intermediate plutons and may include sheeted quartz veins, stockworks, disseminated mineralization, intrusion-hosted veins, skarns, and more distant polymetallic veins. Associated elements can include bismuth, tungsten, arsenic, antimony, and tellurium, although their proportions vary among districts. Orogenic deposits are controlled principally by faults and shear zones formed or reactivated during regional deformation and commonly contain quartz-carbonate veins deposited by fluids moving through stressed crust. Actual deposits may combine features of both models. Fort Knox has a strong intrusive-hosted character, while Pogo combines high-grade structurally controlled quartz bodies with evidence of a magmatic association. Some Interior Alaska prospects instead contain base-metal veins, skarn mineralization, or other hydrothermal systems in which gold is secondary. Deposit models organize observations; they do not replace them. A vein beside granite is not necessarily intrusion-related, and a vein occupying a fault is not necessarily orogenic. Establishing origin requires evidence from crosscutting relationships, mineral paragenesis, alteration, metal associations, fluid inclusions, and radiometric ages. Several hydrothermal events may use the same structure, and later movement may offset or recrystallize earlier mineralization. Reports should therefore state the observed host rock, mineral assemblage, structure, and age evidence before assigning a genetic classification. Where observations support more than one model, the uncertainty should be retained rather than removed for simplicity. [3][8][9][24]
12. Placer Formation, Buried Channels, Bench Gravels, and Permafrost
Interior Alaska placers formed when weathering and erosion released gold from bedrock and streams sorted it according to particle size, shape, density, flow energy, and channel geometry. Gold commonly becomes concentrated near the base of gravel, within bedrock fractures, behind resistant projections, or above compact clay-rich and weathered layers functioning as false bedrock. These positions are tendencies rather than universal rules. Flood magnitude, stream gradient, sediment supply, ice action, channel migration, and bed roughness alter where particles settle or are remobilized. During Pleistocene cold periods, windblown loess and organic-rich silt accumulated across many valleys while permafrost restricted drainage and preserved buried surfaces. Streams migrated and incised at different times, leaving paleochannels and bench gravels above or beside modern channels. Later deposits may conceal older pay gravel beneath alluvium, colluvium, peat, frozen muck, or barren gravel. Historical miners in Fairbanks, Circle, Fortymile, Livengood, and Tolovana sometimes sank shafts through frozen overburden and drifted along auriferous layers near bedrock. A modern surface sample cannot determine the grade of a deeply buried channel, and a productive crevice does not establish the average grade of an entire gravel deposit. Historical use of the word “bedrock” also requires care because miners sometimes applied it to true consolidated rock, decomposed rock, clay, or another compact layer that stopped downward gold migration. Proper placer interpretation requires reconstruction of channel age, elevation, sediment sequence, bedrock profile, source direction, and previous mining disturbance rather than reliance on black sand or isolated pan results. [11][14][15][25]
13. Geological Prospecting Methods and Their Limitations
Prospecting in Interior Alaska is most defensible when several independent observations identify the same target. For lode systems, relevant evidence includes mineralized bedrock, mapped structures, alteration, intrusive contacts, consistent geochemical anomalies, geophysical responses, and mineralogical confirmation. For placers, the critical evidence includes upstream source geology, channel history, gravel stratigraphy, bedrock configuration, gold-particle distribution, and repeatable sample results. Quartz, iron oxides, pyrite, arsenopyrite, stibnite, scheelite, and black sand can be useful clues, but none proves the presence of recoverable gold. Stream-sediment and soil anomalies may be displaced, diluted, enriched by weathering, or obscured by transported cover and permafrost. A single anomalous result must be checked by repeated sampling along a controlled pattern and evaluated against local geology. Historic production confirms that a district contained workable gold under past conditions; it does not establish that accessible, unclaimed, economically recoverable ground remains. Modern recreational prospecting must also be separated from mineral-resource assessment. Much of Interior Alaska consists of State land, federal land, Native corporation land, private property, active claims, patented holdings, parks, withdrawals, and other restricted areas. Claim status, land ownership, access, fish-habitat rules, water use, and equipment restrictions must be confirmed before disturbance. Regional deposit models can guide this work, but district-specific evidence remains controlling. Pogo geology should not be projected automatically onto Fortymile, and Livengood should not be used as a universal model for every placer field. Interior Alaska contains many established gold systems, but its faults, quartz veins, schists, and granitic intrusions are not uniformly mineralized. [13][20][24][26]
14. Conclusion
Gold mineralization in Interior Alaska and the Yukon–Tanana Province reflects several tectonic, magmatic, hydrothermal, erosional, and sedimentary processes rather than one regional event. Metamorphic assemblages were structurally combined, intruded by several generations of magma, and cut by faults that were locally reopened during mineralization. These conditions produced intrusion-related systems, structurally controlled quartz deposits, disseminated mineralization, polymetallic occurrences, and extensive placer fields.
The Fairbanks, Goodpaster, Fortymile, Circle, Eagle, Richardson, Big Delta, Livengood, and Tolovana districts each preserve different relationships among bedrock sources, structures, intrusive rocks, and placer deposits. Their shared regional setting is geologically useful, but evidence from one district cannot be transferred to another without verification.
Historic placer production demonstrates substantial erosion and concentration of gold, while deposits such as Fort Knox, Pogo, and Livengood demonstrate that important lode systems can differ greatly in geometry and mineralogy. Accurate evaluation requires separation of observation from interpretation, lode geology from placer geology, and historic production from present access or recoverability.
15. Related Reading
The Complete Guide to Gold Prospecting Clues: Minerals, Alteration, Veins, and Host Rocks
https://bigrivergold.com/gold-associated-with-stibnite-and-antimony-minerals/
Gold in the United States: State-by-State Geology and Prospecting Guide
https://bigrivergold.com/gold-in-the-united-states-prospecting-guide/
Why Gold Forms, Moves, and Concentrates
https://bigrivergold.com/why-gold-forms-moves-and-concentrates/
How to Read Streams, Benches, Dry Creeks, Desert Washes, Marine Terraces, Dredge Tailings, and Old Placer Ground
https://bigrivergold.com/how-to-read-the-land-for-gold-deposits/
Alaska Gold Prospecting: Statewide Geology, Mining Districts, and Where Gold Occurs
https://bigrivergold.com/alaska-statewide-prospecting/
Gold by US State
https://bigrivergold.com/category/gold-field-by-state/
16. References
[1] Dusel-Bacon, C., 1998. Yukon–Tanana Upland of East-Central Alaska and Yukon: Geological Framework. U.S. Geological Survey Open-File Report 98-340.
https://pubs.usgs.gov/of/1998/0340/
[2] Foster, H.L., Keith, T.E.C., and Menzie, W.D., 1994. Geology of the Yukon–Tanana Area of East-Central Alaska. In: The Geology of Alaska. Geological Society of America.
[3] Hart, C.J.R., Goldfarb, R.J., Lewis, L.L., and Mair, J.L., 2004. The Northern Cordilleran Mid-Cretaceous Plutonic Province: Ilmenite-Magnetite Series Granitoids and Intrusion-Related Mineralization. Resource Geology, volume 54.
[4] Newberry, R.J., Bundtzen, T.K., Clautice, K.H., and others, 1996. Preliminary Geologic Map of the Fairbanks Mining District, Alaska. Alaska Division of Geological & Geophysical Surveys Public Data File 96-16.
https://dggs.alaska.gov/pubs/id/1740
[5] Dusel-Bacon, C., and others, 2002. Studies by the U.S. Geological Survey in Alaska, 2001: Yukon–Tanana Terrane and Related Rocks. U.S. Geological Survey Professional Paper 1678.
https://dggs.alaska.gov/webpubs/usgs/p/text/p1678.pdf
[6] Dusel-Bacon, C., and others, 2024. New U-Pb Geochronology and Geochemistry of Paleozoic Metaigneous Rocks from Western Yukon and Eastern Alaska, Cross-Border Synthesis, and Implications for Tectonic Models. U.S. Geological Survey Professional Paper 1888.
https://pubs.usgs.gov/pp/1888/
[7] Newberry, R.J., and Solie, D.N., 1995. Data for Plutonic Rocks and Associated Gold Deposits in Interior Alaska. Alaska Division of Geological & Geophysical Surveys Public Data File 95-25.
https://dggs.alaska.gov/pubs/id/1704
[8] Goldfarb, R.J., and others, 2007. Geology and Origin of Epigenetic Lode Gold Deposits, Tintina Gold Province, Alaska and Yukon. U.S. Geological Survey Scientific Investigations Report 2007-5289-A.
https://pubs.usgs.gov/sir/2007/5289/SIR2007-5289-A.pdf
[9] U.S. Geological Survey, 2007. Recent U.S. Geological Survey Studies in the Tintina Gold Province, Alaska, United States, and Yukon, Canada—Results of a Five-Year Project. Scientific Investigations Report 2007-5289.
https://pubs.usgs.gov/sir/2007/5289/
[10] McCoy, D.T., and others, 1997. Metallogeny of the Fairbanks Mining District, Alaska. Mineral Industry Research Laboratory, University of Alaska Fairbanks.
[11] Prindle, L.M., 1908. The Fairbanks Gold-Placer Region. U.S. Geological Survey Bulletin 379-E.
https://pubs.usgs.gov/bul/0379e/
[12] Smith, M.T., Thompson, J.F.H., Moore, K.H., and others, 2000. The Liese Zone, Pogo Property—A New High-Grade Gold Deposit in Alaska. In: The Tintina Gold Belt—Concepts, Exploration, and Discoveries.
[13] Wanty, R.B., Wang, B., Day, W.C., Vohden, J., Crock, J.G., and Gough, L.P., 2007. Landscape Geochemistry Near Mineralized Areas of the Goodpaster River Watershed, Alaska. U.S. Geological Survey Scientific Investigations Report 2007-5289-H.
https://pubs.usgs.gov/sir/2007/5289/SIR2007-5289-H.pdf
[14] Yeend, W.E., 1996. Gold Placers of the Historical Fortymile River Region, Alaska. U.S. Geological Survey Bulletin 2125.
https://pubs.usgs.gov/publication/b2125
[15] Mertie, J.B., Jr., 1938. Gold Placers of the Fortymile, Eagle, and Circle Districts, Alaska. U.S. Geological Survey Bulletin 897-C.
https://dggs.alaska.gov/pubs/id/3507
[16] Cathrall, J.B., Albanese, M.D., VanTrump, G., Mosier, E., and Lueck, L., 1989. Geochemical and Mineralogical Data from the Fortymile Mining District. U.S. Geological Survey Open-File Report 89-451.
[17] Bundtzen, T.K., and Reger, R.D., 1977. The Richardson Lineament—A Structural Control for Gold Deposits in the Richardson Mining District, Interior Alaska. Alaska Division of Geological & Geophysical Surveys Geologic Report 55.
[18] Graham, G.E., and Jozwik, D., 2007. Data Tables Related to Geology and Gold Mineralization in the Richardson District, East-Central Alaska. Alaska Division of Geological & Geophysical Surveys Raw Data File 2007-2.
https://dggs.alaska.gov/pubs/id/15819
[19] Twelker, E., Wildland, A.D., Werdon, M.B., and others, 2021. Preliminary Bedrock Geologic Map Database, Northeastern Richardson Mining District, Alaska. Alaska Division of Geological & Geophysical Surveys Raw Data File 2021-9.
https://dggs.alaska.gov/pubs/id/30676
[20] Mueller, S.H., and others, 2007. The Black Mountain Tectonic Zone—A Reactivated Northeast-Trending Crustal Structure in the Yukon–Tanana Terrane of East-Central Alaska. U.S. Geological Survey Scientific Investigations Report 2007-5289-D.
[21] Foster, R.L., 1968. Potential for Lode Deposits in the Livengood Gold Placer District, East-Central Alaska. U.S. Geological Survey Circular 590.
https://dggs.alaska.gov/pubs/id/13515
[22] Twelker, E., and others, 2016. Geologic Map of Portions of the Livengood B-3, B-4, C-3, and C-4 Quadrangles, Alaska. Alaska Division of Geological & Geophysical Surveys Report of Investigation 2016-5.
https://dggs.alaska.gov/webpubs/dggs/ri/text/ri2016_005.pdf
[23] Mertie, J.B., Jr., 1918. The Gold Placers of the Tolovana District. U.S. Geological Survey Bulletin 662-D.
https://pubs.usgs.gov/bul/0662d/
[24] Karl, S.M., and others, 2021. GIS-Based Identification of Areas Having Resource Potential for Critical Minerals in Six Selected Groups of Deposit Types in Alaska. U.S. Geological Survey Open-File Report 2021-1041.
https://pubs.usgs.gov/of/2021/1041/
[25] Ellsworth, C.E., and Parker, G.L., 1911. Placer Mining in the Yukon–Tanana Region. U.S. Geological Survey Bulletin 480-G.
https://pubs.usgs.gov/bul/0480g/
[26] Gough, L.P., Crock, J.G., Day, W.C., and others, 2001. Regional Geochemical Results from the Fortymile and Goodpaster River Watersheds, Alaska. U.S. Geological Survey Bulletin 2191, Chapter 4.
https://pubs.usgs.gov/bul/b2191/b2191_chapter_4.pdf