Showing papers in "Ore Geology Reviews in 2008"

TL;DR: The origin of cratonic diamonds is reviewed on the basis of nearly 5000 analyses of silicate, oxide and sulphide inclusions in diamonds as mentioned in this paper, and compositional fields are defined for common minerals of the peridotitic, eclogitic and websteritic inclusion suites.

TL;DR: In this article, the authors show that heavy rare earth elements (HREE) and yttrium (MEX-REY) mineralization occurs in weathering profiles of parent rocks ranging in composition from granite to acidic volcanic rocks and lamprophyre.

TL;DR: In this paper, stable isotope systematics reflect the style of the three types of gold deposits, but also show that they belong to the same metallogenic system, in which the hydrothermal fluids were derived from a mantle fluid reservoir and mixed with crustal fluids.

TL;DR: In this paper, the authors show that the quality of data-driven prospectivity mapping can be improved by using a training set of coherent deposit-type locations with similar multivariate spatial data signatures.

TL;DR: Kimberlite-hosted diamond deposits are a long-lived and complex series of processes that first involved the growth of diamonds in the mantle, and later their removal and transport to the earth's surface by kimbllite magmas.

TL;DR: The Itacaiunas Belt of the highly mineralised Carajas Mineral Province comprises ca. 2.68 and 2.88-Ga volcanic rocks overlain by sedimentary sequences of ca.2.68-Ga age as mentioned in this paper.

TL;DR: In this article, non-fuel marine minerals are reviewed from the perspective of resources and their value as active analogs that can advance understanding of types of ancient ore deposits that formed in marine settings.

TL;DR: In this article, the authors employed the single grain pyrite Rb-Sr technique to date mineralization, using the example of the Linglong lode gold deposit, Jiaodong Peninsula, eastern China.

TL;DR: In this article, an electron microprobe analyzer was used to map the spatial distribution of visible gold and sub-μm to μm-size visible gold particles in arsenian pyrite in high-grade ore samples from the Shuiyindong mine.

TL;DR: In the classic model, Be-bearing pegmatites interact with Cr-bearing ultramafic or ma�c rocks as discussed by the authors, and it has been demonstrated that circulation processes within the host black shales were sufficient to form emerald.

TL;DR: The Sossego mine as mentioned in this paper contains two major orebodies, Sequeirinho and Sossogo, with coarse-grained zoned actinolite/ferro-actinolites, Cl-apatite, and magnetite within the matrix.

TL;DR: In this article, a fluid inclusion study defines the conditions of gem ruby formation during the retrograde metamorphic path (620 < T < 670 °C and 2.6 < P < 3.3 kbar) for the deposits of Jegdalek, Hunza and northern Vietnam.

TL;DR: The origin of these Outokumpu-type Cu-Co-Zn-Ni-Ag-Au deposits is now interpreted to be polygenetic in this paper.

TL;DR: In this article, a new method is proposed to evaluate mineral occurrence distributions by combining the power of fractal analysis of clustering with the WofE approach, which is applied to copper occurrences in the Proterozoic Mount Isa Inlier, NW Queensland, Australia.

TL;DR: More than 190 occurrences of bauxitic-lateritic deposits were investigated in seven areas within the Zagros Simply Folded Mountain Belt in southwestern Iran as discussed by the authors, where bauxite horizons are situated in eroded major NW-SE trending anticlines and occur in karst cavities near or at the boundary between the Sarvak and Ilam Formations.

TL;DR: Chromitite bodies hosted in the Neoproterozoic western ophiolitic belt of Pampean Ranges of Cordoba (Argentina) were studied at Los Congos and Los Guanacos ultramafic bodies, with regard to the composition and textures of the chromite and platinum group minerals.

TL;DR: Garnier et al. as mentioned in this paper focused on the Late Mesozoic to Cenozoic intraplate basaltic fields of the West Pacific continental margins and reviewed advances made in understanding the genesis of these deposits, based on the application of newer techniques.

TL;DR: In this paper, the results are correlated to the mode of formation and physical properties and are instrumental in establishing the geographical origin of a gem opal, at least for examples from Mexico and Brazil, even if modified by weathering processes.

TL;DR: In this paper, a classification of gem corundum (ruby and sapphire) deposits is proposed, taking into account petrographic data, and the mode of genesis of the deposits.

TL;DR: More than 100 small isolated chromite occurrences form elongated lenses that follow the NW-SE trend of the host serpentinized dunite within a 60 km 2 area 15 km SE of Veria, northern Greece.

TL;DR: The Belgian nonsulfide Zn deposits represent the historical basis for the zinc mining and smelting industry in Europe as discussed by the authors, where the zinc ores were called “calamines” and consist of a mixture of Zn carbonates (smithsonite, hydrozincite) and Zn silicates (hemimorphite, willemite, and zinc clays), with variable content of Pb minerals.

TL;DR: Draa Sfar is a Visean, stratabound, volcanogenic massive sulphide ore deposit hosted by a Hercynian carbonaceous, black shale-rich succession of the Jebilet terrane, Morocco as discussed by the authors.

TL;DR: In this paper, the 18 O/16 O and 13 C/12 C ratios of carbonate minerals formed by supergene oxidation of Zn-Pb deposits and submarine alteration of ancient slags were studied in order to constrain isotope fractionation factors for smithsonite, cerussite, and phosgenite.

TL;DR: In this article, the authors proposed a metallogenetic model based on observations from the Iranian non-sulphide zinc deposits Mehdi-Abad, Iran-Kuh, and Kuh-e-Surmeh.

TL;DR: Cassiterite and wolframite compositions from SnNW- and WNSn-bearing quartz veins in Northern and Central Portugal are compared to provide evidence on fluid compositions as mentioned in this paper, which is attributed to differences in the composition of magmatic hydrothermal fluids.

TL;DR: In this article, in situ ion microprobe sulfur isotope analyses show significant variability for sphalerite (from −43.9 to 1.2‰), galena (from 30.3 to −2.3) and marcasite δ 34 S( from −35.9to 25.8‰).

TL;DR: In this article, the results of an investigation of chromitites occurring in the Kluchevskoy ophiolite complex of the Russian Urals were reported, showing that the chromite composition suggests crystallization from a boninitic magma in a supra-subduction zone geodynamic setting.

TL;DR: The Um El Tuyor gold deposit as discussed by the authors consists of a series of quartz and quartz-carbonate veins, lenses and veinlets, along foliation-concordant and foliationdiscordant fault segments.

TL;DR: Madagascar is one of the most important gem-producing countries in the world, including ruby and sapphires as discussed by the authors, and the majority of the world's gem corundum is mined in the island of Madagascar.

TL;DR: In this article, a combination of a classical approach, based on the algebraic method of Knox-Robinson and Groves, with innovative processing grid-type geochemical and radiometric data, as well as cluster analysis technique provides a better understanding of the structure of studied mineralized areas.