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This location is part of the Arizona Mineral Industry Location System (AzMILS), an inventory of mineral occurences, prospects and mine locations in Arizona. LaPaz43 is located in T7N R13W Sec 11 SE in the Salome - 15 Min quad. This collection consists of various reports, maps, records and related materials acquired by the Arizona Department of Mines and Mineral Resources regarding mining properties in Arizona. Information was obtained by various means, including the property owners, exploration companies, consultants, verbal interviews, field visits, newspapers and publications. Some sections may be redacted for copyright. Please see the access statement.
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Water column redox conditions, degree of restriction of the depositional basin, and other paleoenvironmental parameters have been determined for the Mississippian Kuna Formation of northwestern Alaska from stratigraphic profiles of Mo, Fe/Al, and S isotopes in pyrite, C isotopes in organic matter, and N isotopes in bulk rock. This unit is important because it hosts the Red Dog and Anarraaq Zn-Pb-Ag ± barite deposits, which together constitute one of the largest zinc resources in the world. The isotopic and chemical proxies record a deep basin environment that became isolated from the open ocean, became increasingly reducing, and ultimately became euxinic. The basin was ventilated briefly and then became isolated...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Sulfate is known to be an active oxidizing agent at high temperatures; however, both experimental and geologic evidence indicate that as a hydrothermal solution cools (to about 200 degrees C, depending on pH) kinetic factors slow the rate at which sulfate enters into redox reactions. This retardation of sulfate reduction diminishes the effectiveness of sulfate as an oxidizing agent. Consequently, as cooling proceeds, the reducing effect of H2S (and other reduced species) is not balanced with the oxidizing effect of SO (super -2) 4 to the same extent as at higher temperatures. The result is a progressively more reducing solution, which is precisely what is needed to precipitate reduced uranium minerals and to generate...
Categories: Publication; Types: Citation; Tags: Economic Geology
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This is a point coverage that contains data for coal and otherstratigraphic horizons in the John Henry Member of the StraightCliffs Formation (Upper Cretaceous) east of 112 degrees oflongitude in the Kaiparowits Plateau. The item map# is the numberon the index map (Figure A, Plate 1) that refers to a record in adata table (Appendix 1) in Hettinger and others (1996). Bufferswere drawn at a three-mile distance from data points in thiscoverage to create the reliability coverage. This coverage alsoincludes arcs representing lines of cross section shown in Figs. B,C, D and E, Plate 1 (Hettinger and others, 1996).
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This location is part of the Arizona Mineral Industry Location System (AzMILS), an inventory of mineral occurences, prospects and mine locations in Arizona. Pima196 is located in T11S R16E Sec 15 C in the Bellota Ranch - 15 Min quad. This collection consists of various reports, maps, records and related materials acquired by the Arizona Department of Mines and Mineral Resources regarding mining properties in Arizona. Information was obtained by various means, including the property owners, exploration companies, consultants, verbal interviews, field visits, newspapers and publications. Some sections may be redacted for copyright. Please see the access statement.
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The State of Alaska's Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska's statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. For the geochemical part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly...
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From June 12-21, 2017, the Alaska Division of Geological & Geophysical Surveys (DGGS) geologists carried out geologic mapping and geochemical sampling in the northeastern Tanacross D-1, and parts of the C-1, and D-2 quadrangles. The project area lies within the Yukon-Tanana Uplands, and encompasses the boundary between Fortymile and Lake George assemblages. It includes porphyry copper-molybdenum-gold deposits and prospects including: Taurus, Fishhook (also known as SW Pika), and Pika Canyon, and is adjacent to the Fortymile Mining District to the north. Highlights of this geochemical report include sampling and characterization of the Pika Canyon, Fishhook, and Taurus prospects. This dataset contains four samples...
Tags: Analyses, Analyses and Sampling, Analytical Lab Results, Analytical Results, Base Metals, All tags...
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Kelsey Boltz has been a registered mining engineer and geologist in Arizona since the mid 1960s. A 1953 graduate of the Colorado School of Mines, he founded Colamer Corporation and Nuclear Dynamics, both companies active in the uranium industry in the Grants Uranium Region of New Mexico in the '50s, '60s and '70s. In 1981 he co-founded Century Capital, Inc., an investment banking and retail brokerage firm which provided several hundred million dollars financing for various industries including natural resource companies. In 1990 he started his exploration consulting company, Boltz Group International, which initiated and managed several mining projects in Mexico, Chile and Bolivia. The collection consists of geologic...
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The thermal history of the Oquirrh Mountains, Utah, indicates that hydrothermal fluids associated with emplacement of the 37 Ma Bingham Canyon porphyry Cu-Au-Mo deposit extended at least 10 km north of the Bingham pit. An associated paleothermal anomaly enclosed the Barneys Canyon and Melco disseminated gold deposits and several smaller gold deposits between them. Previous studies have shown the Barneys Canyon deposit is near the outer limit of an irregular distal Au-As geochemical halo, about 3 km beyond an intermediate Pb-Zn halo, and 7 km beyond a proximal pyrite halo centered on the Bingham porphyry copper deposit. The Melco deposit also lies near the outer limit of the Au-As halo. Analysis of several geothermometers...
Categories: Publication; Types: Citation; Tags: Economic Geology
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The mercury-gold deposits of the Ivanhoe mining district in northern Nevada formed when middle Miocene rhyolitic volcanism and high-angle faulting disrupted a shallow lacustrine environment. Sinter and replacement mercury deposits formed at and near the paleosurface, and disseminated gold deposits and high-grade gold-silver veins formed beneath the hot spring deposits. The lacustrine environment provided abundant meteoric water; the rhyolites heated the water; and the faults, flow units, and lakebeds provided fluid pathways for the hydrothermal fluids. A shallow lake began to develop in the Ivanhoe area about 16.5 Ma. The lake progressively expanded and covered the entire area with fine-grained lacustrine sediments....
Categories: Publication; Types: Citation; Tags: Economic Geology
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The experimental metal solubilities for rock-buffered hydrothermal systems provide important insights into the acquisition, transport, and deposition of metals in real hydrothermal systems that produced base metal ore deposits. Water-rock reactions that determine pH, together with total chloride and changes in temperature and fluid pressure, play significant roles in controlling the solubility of metals and determining where metals are fixed to form ore deposits. Deposition of metals in hydrothermal systems occurs where changes such as cooling, pH increase due to rock alteration, boiling, or fluid mixing cause the aqueous metal concentration to exceed saturation. Metal zoning results from deposition occurring at...
Categories: Publication; Types: Citation; Tags: Economic Geology
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The final event in a complicated hydrothermal history at the Meikle gold deposit was gold deficient but caused extensive postore dissolution of carbonate, collapse brecciation, and precipitation of calcite and barite crystals in the resulting cavities. Although previously interpreted to be part of the Carlin-type hydrothermal system, crosscutting relationships and U-Th-Pb geochronology constrain this hydrothermal event to late Pliocene time (ca. 2 Ma), nearly 36 Ma after ore formation. Mineralogic, fluid inclusion, and stable isotope data indicate that postore hydrothermal fluids were reduced, H2S-rich, unevolved meteoric waters ((??18O = -17???) of low temperature (ca. 65??C). The ??18O values of barite and calcite...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Analysis of the heavy metal content in a Holocene-Pliocene red bed sequence near San Felipe in N Baja California, Mexico, has yielded new information on the mobility and distribution of these metals during ageing of iron oxyhydroxides from the amorphous to the crystalline state. Whole-rock samples (27) and a series of successive leachates were analysed for V, Al, Cr, Mn, Fe, Co, Ni, Cu and Zn by ICP spectrometry and for U by a delayed neutron technique. These data are supported by a variety of other mineralogical and petrographical observations. The results indicate that the metal content of the samples is predominantly inherited from the constituent detrital minerals. Reddening of the whole-rock samples does not...
Categories: Publication; Types: Citation; Tags: Economic Geology
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The Laramide San Manuel-Kalamazoo porphyry system of Arizona has been pivotal in concepts of both extensional tectonics and alteration-mineralization zoning. This paper reexamines the tilting history in light of new work in the region and reinterprets the geometry of the deposit. The porphyry mineralization occurs in and near an intrusion of Laramide San Manuel porphyry in Precambrian Oracle Granite. The area has an extremely complicated history of Tertiary crustal extension and fanglomerate deposition, but the blocks containing the two main fragments of the original orebody were involved in only the later parts of this history and are less tilted than other nearby blocks. Originally horizontal features of mid-Tertiary...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Two major periods of uranium mineralization are indicated by U-Pb isotope dating of uranium ores from collapse breccia pipes in the Grand Canyon region, northern Arizona. The Hack 2 and 3, Kanab North, and EZ 1 and 2 orebodies apparently formed in the interval of 200 ?? 20 Ma, similar to ages inferred for strata-bound, Late Triassic-hosted uranium deposits in southern Utah and northern Arizona. Samples from the Grand Canyon and Pine Nut pipes, however, indicate a distinctly older age of about 260 Ma. The clustering in ages for a variety of uranium deposits at about the age of the lower part of the Chinle Formation (Late Triassic) suggests that uranium in these deposits may have been derived by leaching from volcanic...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Lead from galena of massive sulphide deposits in the metavolcanic belt of northern Wisconsin was probably derived from 3700 m.y. old source material 1800-1900 m.y. ago. Approximately 3500 m.y. old rocks occur within 100-300 km to the north and west. The U-Th-Pb systems of the metavolcanic and granitic rocks in the belt were reset about 1600 m.y. ago during retrogressive metamorphism. The ages from lead isotope data are in accord with Rb/Sr whole-rock, Rb/Sr and K/Ar mineral, and U-Th-Pb zircon dating. A concordia plot of whole-rock lead data shows that many of the rocks lost lead 200-400 m.y. ago during uplift and erosion. Meta-volcanic rocks near Crandon, Wisconsin, had lead isotope compositions 20 m.y. ago that...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Presents a quantitative simulation of regional groundwater flow during uranium deposition in the Westwater Canyon Member and Jackpile Sandstone Member of the Upper Jurassic Morrison Formation in the San Juan basin. Topographic slope, shoreline position, and density contrasts in the lake and pore fluids controlled the directions of flow and recharge-discharge areas. The most important results for uranium ore deposit formation are that regional groundwater discharged throughout the basin, regional discharge was concentrated along the shore line or playa margin, flow was dominantly gravity driven, and compaction dewatering was negligible. A strong association is found between the tabular sandstone uranium deposits...
Categories: Publication; Types: Citation; Tags: Economic Geology
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The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ34S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes (207Pb/204Pb >19.2; 15 analyses) acquired from clastic detritus eroded from Precambrian cratonal rocks to the east-southeast. In the overlying Paleozoic section, Pb-Zn-Cu-Ag-Au deposits associated with Jurassic, Cretaceous, and Tertiary granitic intrusions (intrusion-related metal deposits) contain galena and other sulfide minerals with S and Pb isotope compositions...
Categories: Publication; Types: Citation; Tags: Economic Geology
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Guy Atlee lived and worked in the Kingman area working the Turquoise mine (Mineral Park) and other mines near Chloride (IXL, Wrigley), Cerbat, and Kingman. He is known to have worked and traveled in the Victorville, Topock and other areas of California. Guy’s wife was Rose Atlee and they had a large family. The collection includes images of mines and workings as well as many images depicting daily life in Mohave County. The photos appear to cover a period from about the turn of the century through the 1920s.
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This collection consists of economic geologic information on Anderson Mine and Date Creek area collected from the late 1960s to the late 1970s. It contains geologic reports, maps, assays, drill logs and related materials.


map background search result map search result map Guy Atlee mining photo collection Anderson Mine collection Kelsey Boltz mining collection inventory Point source data for coal in the John Henry Member of the Straight Cliffs Formation in the Kaiparowits Plateau study area ADMMR mining collection file: Critic Mine ADMMR mining collection file: Corregedor Mine Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska Major-oxide and trace-element geochemical data from rocks collected in the Tanacross C-1, D-1, and D-2 quadrangles, Alaska in 2017 ADMMR mining collection file: Corregedor Mine ADMMR mining collection file: Critic Mine Major-oxide and trace-element geochemical data from rocks collected in the Tanacross C-1, D-1, and D-2 quadrangles, Alaska in 2017 Point source data for coal in the John Henry Member of the Straight Cliffs Formation in the Kaiparowits Plateau study area Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska Guy Atlee mining photo collection Kelsey Boltz mining collection inventory