 | | Journal (article/letter/editorial) | | ORIGIN OF THE EL LACO MAGNETITE DEPOSIT, NORTHERN CHILE RICHARD H. SILLITOE† 27 West Hill Park, Highgate...Plio-Pleistocene volcanic arc of Region II, northern Chile, and comprises seven discrete bodies of massive...associated hydrothermal alteration, El Laco, northern Chile (latitude, 23°50'29.6"; longitude, 67°29'24.6")...elsewhere (e.g., Manto Verde copper deposit, northern Chile; Vila et al., 1996). Similar observations, also...lined by tiny magnetite octahedra and traces of apatite and quartz. “Vug” and “chimney” are employed herein |  | CIGOLINI, Corrado, DI MARTINO, Mario, LAIOLO, Marco, COPPOLA, Diego, ROSSETTI, Piergiorgio, MORELLI, Marco (2012) Endogenous and nonimpact origin of the Arkenu circular structures (al‐Kufrah basin—SE Libya) Meteoritics & Planetary Science, 47 (11) 1772-1788 doi:10.1111/maps.12012 | Journal (article/letter/editorial) | | fragmental feldspathic material (containing magnetite, apatite, barite, and Mn and Zn oxides) that is overlain...places shows silicified syenite clasts embedded in apatite-rich veinlets. Pervasive hydrothermal alteration...(1991) and Nyström and Henriquez (1994) for Magnetita Pedernales and Kiruna-type deposits, respectively,...carbonate, ankerite, and Fe-Mn oxides. Sparse zircon, apatite, and rutile are accessory phases. The second type...ankerite, and Fe-Mn oxides (in veinlets). Zircon, apatite, rutile, allanite, opaques (Ti-magnetite and ilmenite) |  | | Journal (article/letter/editorial) | | SCIENTIFIC MAGNETITA PEDERNALES: COMMUNICATIONS A NEW MAGMATIC IRON DEPOSIT IN NORTHERN CHILE ENRIQUE...AGUILAR, Gold Fields Chile S.A., CarmenSilva 2449, Casilla 9134, Santiago,Chile FERNANDO HENRIQUEZ,...Universidadde Santiago,Casilla 10233, Santiago,Chile AND JAN OLOV NYSTROM SwedishMuseumof Natural History...approximately200 km northeastof Copiap6in northern Chile (Fig. 1). It is situatedat an altitude of ca. 3...the iron oresat E1Laco, which is farther north in Chile (Fig. 1). E1 Laco is a The MagnetitaPedernalesdepositis |  | | Journal (article/letter/editorial) | | TRAVISANY, PintorJ. Gil de Castro7862,Santiago,Chile FERNANDO HENRiQUEZ, Departamentode Minas, Universidadde...Universidadde Santiago,Casilla 10233, Santiago,Chile AND JANOLOV NYSTROM SwedishMuseumofNatura I History...transcurrent,is a copper-bearing mined for iron and/or apatite, and four smallcopperde- magnetitedike situatedca...extensivelydevelopedin the andesmore than 400 km along central Chile. Moscosoet al. 0361-0128/95/1683/438-7 $4.00 438...sof pegmatiticappearance composedof amphibole,apatite,and minorto trace amounts FIG. 2. Geologicmapof |  | | Journal (article/letter/editorial) | | (pi); clinopyroxene (cpx); Ti-magnetite (mag); apatite (ap). (Note absence of spinel phase from LMZ-UMZ...sulphides are ubiquitous accessory constituents. Apatite may also be present. Plagioclase, magnesian olivine...the Union pegmatites (SK-2/1, -3, -10, and -11). Apatite is not observed in pegmatites from the UCZ, but...1097 m is related to the occurrence of apatite (Fig. 14B). Apatite only enters as a cumulus phase in UZc.../ ' ^ 100 100 A Apatite-bearing *>/ ML-24 ML-27 *| V II 'II3 • Apatite-free • 2 . AM + 111 |  | | Journal (article/letter/editorial) | | occurrences are so-called nelsonites (ilmenite + apatite rocks), oxideapatite gabbronorites (OAGNs), and...all localities (Fig. 2b). The Blue Mountains province is a complex assemblage of at least four oceanic...K-feldspar is interstitial. Accessory minerals are apatite, sphene, and zircon. Blue-green cordierite occurs...+ biotite + plagioclase + quartz + muscovite + apatite cordierite K-feldspar (Table 1). ORTs exhibit...approximately 1 cm in length). Large euhedral apatite crystals reach 5% by volume. Coarse-grained leucotonalite |
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