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Showing 1 to 11 of 11 for “"HFSE"”.
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The geochemistry of the Atlanta Lobe of the Idaho Batholith in the western United States, Cordillera
… granitoids are characterised by high LILE/HFSE and LREE/HREE ratios, low Rb/Sr and Snx/Ndr atios and F-Nda End ESro f -4.9 to -11.6 and 35 to 120 respectively. Only the tonalites and silicic granodiorites to granites underwent significant degrees of within suite fractional crystallization, …
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NEW TECHNIQUES FOR TRACE ELEMENT AND RADIOGENIC ISOTOPE MEASUREMENT OF DIAMONDS: THEIR APPLICATION TO DIAMOND PETROGENESIS AND SOURCE TRACING
… Diamonds show broad LILE and LREE enrichment and HFSE and HREE depletion. Trace element systematics in fibrous diamonds are mimicked in monocrystalline diamonds. Monocrystalline diamonds display 87Sr/86Sr(i) = 0.7014±0.0010 to 0.70864±0.00004 and fibrous diamonds display 87Sr/86Sr(i) = …
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Geochemical investigation of Meso- to Neoarchean (3075–2800 Ma) supracrustal rocks in the Nuuk region, southern west Greenland
… (HREE) and high field strength elements (HFSE: Th, Nb, Ta, Zr, Ti) remained relatively immobile during stage-I alteration but were variably disturbed during the stage-II metasomatism. Transition metals (e.g., Ni, V, Co, Cr, and Sc) were immobile during both metasomatic events. The …
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Volcanic framework and geochemical evolution of the Archean Hope Bay Greenstone Belt, Nunavut, Canada
… that vary in trace elements particularly HFSE and REE’s, and can be easily be distinguished by geochemical screening. The felsic volcanic suites are also divided into three main groups, tholeiitic rhyolite, calc-alkaline dacite and calc-alkaline rhyolite groups. Nd and Hf isotope …
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The tectonic evolution of the Southern Granulite Terrane of India and its role in the amalgamation of Gondwana.
… granitic to granodioritic, with high LILE/HFSE and LREE/HFSE ratios, low Ni and Cr concentrations typical of magmas generated above a subduction-zone. The differences in the structural character, age and geochemistry of the basement gneissic rocks as well as the differences in the …
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The stratigraphic and structural controls on copper-gold mineralization at Cassenha hill prospect, within the Archean to Paleoproterozoic Angolan shield, Congo craton, South Western Angola
… LREE and LILE elements and depleted in HREE and HFSE elements; (6) The mineralization is associated with chloritization alteration and predominantly occurs within and/or at the edges of quartz/chlorite-rich veins/fractures and is not restricted to any rock type. Two ore stages could be …
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The timescales of andesite generation at Mount Ruapehu, New Zealand
… Trace element patterns show high LILE/HFSE ratios characteristic of arc lavas. AFC models of isotope data suggest that 50% crystallisation and 10-15% assimilation can explain the observed trends. The assimilant is likely to have been dominated by partial melts of local Torlesse …
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Association of S-type and I-type granitoids in the Neoproterozoic Cameroon orogenic belt, Bafoussam area, West Cameroon : geology, geochemistry and petrogenesis
… a wide range of high-field-strength elements (HFSE) and large ion lithophile elements (LILE) contents, with felsic granitoids being enriched in HFSE and the intermediate granitoids displaying in contrast high LILE concentrations. They exhibit chemical characteristics of non-alkaline to …
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Lithium, Beryllium and Boron in High-Pressure Metamorphic Rocks from Syros (Greece)
… tourmaline. The light elements Li and Be, the HFSE, the REE, Y and the LILE all show very low concentrations. First row transition metals and Sr, Pb and Ga are incorporated into dravite, demonstrating abundances in the same order as in the respective whole rocks, and in paragenetic rock-forming …
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Petrology and geochemistry of the granitoids of the Halfway House Dome
… characteristic features of the HHD TTG’s include HFSE depletion and distinct enrichment of fluid sensitive elements such as Pb. The strongly fractionated REE pattern, high (La/Yb)N ratio and depletion in HREE (Yb) of the Halfway House Dome TTGs are characteristics shared with modern adakites. The …
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Paleocene Turbidite Deposition in the Central American Seaway (NW Costa Rica): Geochemical Analysis and Provenance of Detrital Spinel and Clinopyroxene
The Central American Land Bridge is the crucial connection between North and South America, and the Miocene closure of the Panama seaway led to a change in global oceanic circulation patterns. Modern Costa Rica is part of the island arc that formed over the western Caribbean subduction zone, and …