 | | Journal (article/letter/editorial) | | VolcanicRocksof the La Libertad Gold Mining District and Its Surroundings,Nicaragua MAURICIO DARCE* Departmentof...urroundinga swarmof auriferousquartzveinsat La Libertad,Nicaragua.The outermostzone (I) is affectedby...wairakite subfacies). A steepthermal gradientat La Libertad, exceeding150øC/km, revealsthat the mining districtis...40 depositsin Nicaragua(Fig. 1), but there are only two km west-northwest of La Libertad contains similar...typicaldis- unit elsewherein the La Libertad region and its vitrict, La Libertad andits surroundings. The geologic |  | | Journal (article/letter/editorial) | | Miocene Santa Lucía Volcano, Boaco district, Nicaragua David Buriánek1*, Petr HRADECKÝ2 1 2 * Czech...south-western part of the Chortis Block in Central Nicaragua. Six main lithological units were recognized:...with wider Tertiary volcanic areas in Central Nicaragua will contribute to the knowledge of the regional...Lucía region into three units: Santa Lucía, La Libertad and Las Maderas. This simple subdivision facilitates...central part of Nicaragua. Similarly to the surrounding volcanic centres (Las Lajas, La Luna and San Lorenzo) |  | | Journal (article/letter/editorial) | | metamorphic, and metasomatic systems Shelby T. Rader, Frank K. Mazdab, Mark D. Barton PII: DOI: Reference: S0016-7037(18)30536-2...SYSTEMS Shelby T. Rader*, Frank K. Mazdab, Mark D. Barton Department of Geosciences and Lowell Institute...Corresponding author. Present address: Shelby T. Rader, Department of Environmental, Earth, and Atmospheric Sciences...isotopic composition data for potassium feldspar (K-feldspar), micas, sulfides, and other minerals using...MC-ICP-MS) to 3200 ppm. In this present study, mica and feldspar samples can reach Tl concentrations well over |  | Camprubí, Antoni, González-Partida, Eduardo, López-Martínez, Margarita, Iriondo, Alexander, Alfonso, Pura, Cienfuegos-Alvarado, Edith, Gutiérrez-Armendáriz, Eric, Morales-Puente, Pedro, Canet, Carles, González-Ruiz, Luis (2017) The Upper Cretaceous Guaynopa IOCG and Guaynopita porphyry copper deposits, Chihuahua, Mexico. Ore Geology Reviews, 81. 1096-1112 doi:10.1016/j.oregeorev.2016.01.006 | Journal (article/letter/editorial) | | 22860 Ensenada, Baja California (Mexico) d Department of Geological Sciences, Jackson School of Geosciences...Catalonia (Spain) f Programa de Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México....accompanied by potassic (fuchsite, biotite and potassium feldspar) and/or calcic-sodic alteration (tremolite-actinolite)...chalcopyrite, pyrite, sphalerite, Ag-rich gold, cuprite, K-feldspar, some tremolite-actinolite and kaolinite, besides...long, 600 m deep, and average 0.80 m thick (La Libertad vein), and are hosted by the RI limestone sequence |  | Haeberlin, Y., Moritz, R., Fontbote, L., Cosca, M. (2004) Carboniferous Orogenic Gold Deposits at Pataz, Eastern AndeanCordillera, Peru: Geological and Structural Framework, Paragenesis, Alteration,and 40Ar/39Ar Geochronology. Economic Geology, 99 (1) 73-112 doi:10.2113/gsecongeo.99.1.73 | Journal (article/letter/editorial) | | ROBERT MORITZ, LLUÍS FONTBOTÉ, Section des Sciences de la Terre, Université de Genève, Rue des Maraîchers 13...their country rocks. They drew attention to a 287 Ma K/Ar muscovite age of the mineralization that significantly...methods and minerals U/Pb zircon 39 Ar/ Ar biotite K/Ar biotite (minimum ages) 40 347±7.3 Ma (a) Chiclayo...been dated between 347.0 ± 7.3 and 321 ± 1 Ma, using K/Ar, 40Ar/39Ar, and U/Pb methods (Fig. 2). Trace and...of the province above Huaylillas (Fig. 1), is the La Estrella Fe ± Au skarn, with gold grades of as much |  | | Journal (article/letter/editorial) | | Chiaradia (&) Æ L. Fontboté Section des Sciences de la Terre, Université de Genève, Rue des Maraı̂chers...magmatic rocks can also be obtained by analyzing K-feldspar (e.g., Carignan et al. 1993) because this mineral...studies based on the isotopic signatures of single K-feldspars, which may be different from those of the...250 and 300 mg of powdered rock and 50 mg of K-feldspar were leached at 180 °C in 3.5 ml of 7 M HCl and...on a MAT-Finnigan 262 mass spectrometer at the Department of Mineralogy of the University of Geneva (Switzerland) |  | | Journal (article/letter/editorial) | | alteration dominated by inner biotite and outer K-feldspar-calcite-quartz-sericite (Rhys, 1995). The mining...vein-related alteration gave an appreciably younger K-Ar age of 286.5±6.4 Ma (Vidal et al., 1995). Numerous...the The Dongping veins cut syenite and alkali feldspar Pataz batholith, but significantly less radiogenic...combined with the fluid-inclusion and of quartz±K-feldspar, and are associated with broad Klead-isotopic...results, led both Schreiber et al. (1990) and feldspar haloes as much as >10 m wide (Zhang and Mao, Vidal |  | | Report (issue) | | Aguirre-Diaz Unidad de Investigacion en Ciencias de la Tierra Universidad Nacional Aut6noma de México Campus...Delgado-Argote iil ee Contents Hl, Stratigraphy, K-Ar ages, and magnetostratigraphy of the Acambay graben...Trans-Mexican Volcanic Belt, and provide an important set of K-Ar data and chemical analyses of the products of the...al i) \ | 15 \OT. | ae (eee -110 Lo OFZ =k -105 COCOS PLATE 1 L | | 1 J -100 Figure 1...L\ . Y JALISCO! f, RIVERA \ PLATE IA \ K LOCK | te S < a (dALISCO’ \\— LOCK // WK» |  | Witt, W. K., Hagemann, S. G., Villanes, C., Vennemann, T., Zwingmann, H., Laukamp, C., Spangenberg, J. E. (2016) Multiple Gold Mineralizing Styles in the Northern Pataz District, Peru. Economic Geology, 111 (2) 355-394 doi:10.2113/econgeo.111.2.355 | Journal (article/letter/editorial) | | Mineralizing Styles in the Northern Pataz District, Peru* W. K. Witt,1 S. G. Hagemann,1 C. Villanes,2 T. Vennemann...that deposited the Mississippian Lavasen Volcanics. K-Ar and 40Ar-39Ar ages for hydrothermal illite from...http://econgeol.geoscienceworld.org/. **Present address: Department of Geology and Mineralogy, Kyoto University,...(Miskovic et al., 2009). Methods This study used the K-Ar method to obtain minimum ages for white mica samples...impressive form of the plateaus. We applied illite K-Ar dating to eliminate 39Ar recoil problems, which |  | | Journal (issue) | | Quiruvilca District, Santiago de Chuco Province, La Libertad Department, Peru, Bill and Carol Smith display. 1...reat too. Carolyn Mancheste r s howed us that bla c k min era ls- hematite and gocthite- can be beauti fu...Congo, of various sizes. They were not boxed, nor la be lled, but just lying together on a table between...desig ned a nd made jewa e_Iry myself, I_was s truc k by the imagi na tion. beauti ful execu"W 11011 and...mentioned before. severa l .. us uals'' were not there: A la in Carion. Luis Menezes, a mong them. Quite a number |  | | Journal (article/letter/editorial) | | lowermost mantle M.G. KOPYLOVA AND P.C. HAYMAN Department of Earth and Ocean Sciences, The University of...Earth Planet Sci Lett 222:435-449 Murakami M., Hirose K., Sata N., and Ohishi Y., (2004). Eos Trans. AGU,...EOS with: ρ0 = 4.05g/cm3, K = 180 GPa, K′ = 6, γ = 1.15, q = 0.8, Cv = 1.55 J/K/g. The melting of CaCl2...at ~5000 K at 135 GPa. Also the α-PbO2-structured SiO2 EOS is described by : ρ0 = 4.18 g/cm3, K = 270 GPa...GPa, K′ = 3.6, γ = 1.35, q = 2.6, Cvm = 1.215 J/K/g, θ0 = 1222 K. Examination of the diamond anvil melting |  | | Report (issue) | | oportunidades para el desarrollo de recursos DEPARTMENT OF THE INTERIOR DONALD PAUL HODEL, Secretary...Resources Support for Central America, by Ronald K. Lohrding and John T. Whetten 65 Programa de Asesoramiento...Minerales y Energeticos para America Central, por Ronald K. Lohrding y John T. Whetten 67 Developing a Comprehensive...Assessment for Central America, by Wendell A. Duffield ll3 La Evaluacion de Recursos Geotermicos en Centroamerica...Assessment in the Tropics, by Donald B. Hoover 196 La Aplicacion de los Metodos Geofisicos Electricos en |  | | Report (volume) | | West 920 Riverside Ave. WASHINGTON, D.C.--U.S. Department of the Interior Bldg., Rm. 2650, 1849 C St.,... U.S. GEOLOGICAL SURVEY BULLETIN 1693 U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary...-----------(34b) Regionally metamorphosed rocks K. Derived mainly from eugeosynclinal rocks Low-sulfide...useful sources for multiple deposit types (Canada Department of Energy, Mines and Resources, 1980; DeYoung...EXAMPLES Stillwater Complex, USMT High Mg; low Na, K, and P. (Page , 1977) 11 Model 1--Con. -A.-A.- |  | | Journal (article/letter/editorial) | | central Baja California peninsula: the record of the La Unión complex, Baja California, Mexico T.A. Peña-Alonsoa...(Received 3 July 2014; accepted 14 November 2014) The La Unión volcanic–plutonic complex is located near the...margin of the Peninsular Ranges batholith (PRb). La Unión complex rocks are grouped into prebatholithic...transpression (D1) generated between ca. 128 and 132 Ma. The La Unión complex interfingers with the Nuevo Rosarito... International Geology Review a key area: the prebatholithic La Unión volcanic–plutonic complex. These data are contrasted |  | Hodges, C.A., Cox, D.P., Singer, D.A., Case, J.E., Berger, B.R., Albers, J.P. (1984) U.S. Geological Survey-INGEOMINAS mineral resource assessment of Colombia. Open-File Report Vol. 1984 (84-345) US Geological Survey doi:10.3133/ofr84345 | Report (issue) | | UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY U.S. GEOLOGICAL SURVEY-INGEOMINAS MINERAL...their dense quartz stockwork, stable potassium feldspar in altered rocks, and yellow ferrimolybdite stains...others, 1963). Copper deposits described from the La Quinta Formation in adjacent parts of the Perija...listed above and comprise the Giron, Guatapuri and La Quinta Formations in the Cordillera Oriental, Santa...deposits being mined at Cerro Matoso, in the department of Cordoba, contain 2.6 percent Ni, 0.06 percent |  | | Journal (issue) | | Rothschild (deceased) Philip G. Rust (deceased) Bryan K. Lees (2008-2015) Stephen Neely (2008-2015) Stuart...Carter (2012-2017) Wally Mann (2012-2016) George K. Hickox, Jr. (2012-2015) David E. Ellis (2012-2015)...unusual, organics-rich sedimentary rocks in the Department of Boyaca in west-central Colombia. From the...late 20th century, when the Gachala, Penas Blancas, La Pita and other deposits were first worked, these...deposits: The Western Belt consists of the Muzo, La Pita, Cosquez, La Marina and Penas Blancas mining areas, whereas |  | | Report (issue) | | UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY PRELIMINARY DEPOSIT-TYPE MAP OF NORTHWESTERN...geologicas-mineras sobre cobre en los prospectos de "Los Alisos", "La Caridad" y "El Alacran"- Reconocimiento geologico...L., and Gomez Caballero, A., 1986, Resultados de la evaluacion del deposito de boratos del area Tubutama...Society Digest, v. 14, p. 237-262. Vlll Busch, K., (ed.), 1980, Mexiko kupfer/zink/blei/gold/silber...hierro de La Perla y La Negra, municipio de Camargo, Chihuahua [Iron deposits of La Perla and La Negra, |  | | Book | | massive calcite. or, rarely, still attached to the feldspar/mica walls of the dike (www.davidkjoyceminerals...specimens in which euhedral crystals of andesine feldspar, augite and ilmenite rest on matrix of fine-grained...enclosed by a rind of sandstone and chert (Zzyzx, 201 la). The first specimens of crystallized inesite from...tum brownish (Zzyzx, 201 la). INDERITE UNITED STATES and CANADA CALIFORr-.'lA Kramer deposit, Boron,...6 EUROPE ITALY Monte Nero mine, Rocchetta Vara, La Spezia, Liguria. With the extension of quarrying |  | | Journal (issue) | | dark green elbaite, some pink and red elbaite, K-feldspar and cleavelandite (albite) have also been produced... EXPLANATION Pegmatite deposits showing di p TOM K wm(?) Woodson Mt.(?) granodio rite Kgym Green...contains major quartz and albite, with less abundant K-feldspar and schorl. Muscovite and almandine-spessartine...schorl and lesser amounts of muscovite and garnet. K-feldspar m ega cry sts as much as 1 0 cm long flare outward...three-dimensional continuity of the quartz and feldspar individuals in the graphic intergrowths. The distribution |  | | Journal (issue) | | unit 6 La Victoria unit 6 Depositional age of the Tahuin division 9 Moromoro granitoid complex 10 La Bocana...Bocana unit 10 La Florida unit 13 Marcabeli and El Prado plutons 13 Age of La Bocana unit and Marcabelf...Non-metallic mineral occurrences 48 Jerusalein feldspar mine 48 Quarrying operations 49 Brick clays 49...Sm/Nd isochron diagram for garnet-bearing paragneiss, La Bocana unit, Moromoro complex, Rio Piedras 16 6 U/Pb...complex 30 14 ROCK/ORG normalised spider diagram for La Bocana unit, Moromoro complex 30 15 ROCK/ORG normalised |  | | Book | | Junction Editors Fabio Cediel Consulting Geologist Department of Geology University EAFIT Medellín, Colombia...Island, Chocó Arc, Sierra Nevada de Santa Marta, La Macarena, and the Guiana Shield: remote regions studied...E.) Geochemical Journal v. 15 p. 141–161. 2000 – La Macarena, Massagno, Switzerland (self-published)...(self-published), 111 p. Biographies Augusto Gansser (2000) La moglie di un geólogo, 2nd edn Massagno, Switzerland...the basis for the self-published biographical work “La moglie di un geologo: Augusto Gansser.” Acknowledgments |  | | Book | | Oxford OX2 6DP Oxford University Press is a department of the University of Oxford. It furthers the...scope of the above should be sent to the Rights Department, Oxford University Press, at the address above...rock with rhombic grains of feldspar in a finegrained matrix. The feldspar grains were formed in the magma...complex, Greenland. The rock consists mainly of feldspar (white), nepheline (greyish white), arfvedsonite...on the a axis = a/h, intercept on the b axis = b/k, intercept on the ¢ axis = c/l, as (hkl). where |  | | Journal (issue) | | (2009–2017) Arizona Mineral Minions (2016) FELLOWS Bryan K. Lees (2008–2016) Stephen Neely (2008–2016) Stuart...Carter (2012–2017) Wally Mann (2012–2016) George K. Hickox, Jr. (2012–2017) David E. Ellis (2012–2017)...age of 288 million years was determined using the K/Ar method. When the Brocken granite intruded into...there are many rare secondary species. Ernst Vein k üc gl ns an rm He in Ve LT AU GF ost Vein...of chervetite have been identified. Agardite-(La) (La,Ca)Cu6(AsO4)3(OH)63H2O Agardite was first described |  | | Journal (issue) | | 4 57 b y S. L. C is n e ro s , R. E. W itk o w s k i a n d D. L. O s w a ld F a m o us M in e ra l L...ngeles County 487 b y P e te r C K e lle r a n d A n th o n y R. K a m p f M in e ra ls o f th e Blue...C o u n ty , C a lifo rn ia . . . 4 94 b y J a c k A. C ro w le y V uagn atite fro m C a lifo r n ia...e n t, D on M ills , O n ta rio M 3 C 1 N 8 E n g la n d : Dr. R .S. H a rk e r, 2 W e ils ic Lane, R...B E n g la n d S o u th A fric a : H o rs t W in d is c h , 3 0 va n W o u w St., G ro e n k lo o f, |  | | Journal (issue) | | minerals. Please do something! E3 by Pete J. Dunn Department of Mineral Sciences Smithsonian Institution Washington...younger in age on the basis on their graptolite fauna. K-Ar dates of ± 480 million years (Poole et al., 1963)...post-date the ultramafics and a ± 360 million year K-Ar date on a Jeffrey mine granitic rock, reported...on granitic rocks, associated with diopside, K-feldspar and quartz. Particularly attractive are those...hemispheres —on serpentine matrix Biotite Brucite K(Fe,Mg)3(Al,Fe)Si3O 10(OH)2 Mg(OH)2 Essential constituent |
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