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At Sams Creek, a gold-bearing, peralkaline granite porphyry dyke, which has a 7km strike length and is up to 60m in thickness, intrudes camptonite lamprophyre dykes and lower greenschist facies ...
Khan Bogd Peralkaline Granite, Khanbogd District, Ömnögovi Province, Mongolia : The largest known intrusion of peralkaline granites. ... O., & Kirwin, D. Geodynamics and Metallogeny of Mongolia with a special emphasis on copper and gold deposits. IAGOD guidebook series, 11. CERCAMS/Natural History Museum, London, 131-148. Dostal, …
At Sams Creek a gold-bearing, peralkaline granite pophyry dyke intrudes Ordovician-Silurian metapelite and quartzite. The granite porphyry dyke has a thickness of up to 40 …
The Central Asian Orogenic Belt (CAOB) that stretches from the Ural Mountains to the Pacific Ocean, is one of the world's largest accretionary orogens (Fig. 1 a; Jahn, 2004).There are many peraluminous and alkaline/peralkaline granite associated with rare-metal mineralization formed in an intracontinental environment during Late …
The peralkaline granitic intrusions are spatially associated with calc-alkaline granitic intrusions, and they together constitute part of the Cretaceous high-silica I–A composite type granite belt along the present coastal area of SE China (e.g., Zhao et al., 2015, Zhao et al., 2016, Chen et al., 2021a, Chen et al., 2021b).
Despite numerous studies on post-collisional peralkaline granites in the Egypt Eastern Desert, their origin and geotectonic evolution remain uncertain [12]. Mount El-Sibai (640–590 Ma; [13]), situated in the central Eastern Desert of Egypt (Figure1b), is a significant peralkaline intrusion. Previous studies have examined the petro-
To investigate the generation of H2 during alteration of peralkaline granites, we performed hydrothermal experiments on pure arfvedsonite grains and arfvedsonite-bearing granite (10 wt ...
Gold is associated with arsenopyrite–pyrite–quartz–siderite mineralisation in a peralkaline granite porphyry dyke which intrudes Lower …
DOI: 10.1016/J.GCA.2021.05.048 Corpus ID: 236300672; Hydrogen generation during hydrothermal alteration of peralkaline granite @article{Truche2021HydrogenGD, …
The peralkaline composition of the Sams Creek granite and the absence of molybdenite and paucity of chalcopyrite, are major points of difference with gold-rich porphyry …
Peralkaline syenite and granite dykes cut the Straumsvola nepheline syenite pluton in Western Dronning Maud Land, Antarctica. The average peralkalinity index (PI = molecular Al/[Na + K]) of the dykes is 1.20 (n = 29) and manifests itself in the presence of the Zr silicates eudialyte, dalyite and vlasovite, and the Na–Ti silicate, narsarsukite.
Mineralogical and stable isotope studies of gold–arsenic mineralisation in the Sams Creek peralkaline porphyritic granite, South Island, New Zealand
Peralkaline granite. Mostly medium-grained hypidiomorphic granular granite containing subhedral to euhedral perthite (Nelson and others, 1983) in the Lake Clark quadrangle. This peralkaline granite is spatially associated with the Alaska-Aleutian Range batholith. Alternatively, this pluton may be associated with plutons of unit Tgw.
Compositional and textural data are presented for zircon, secondary Zr-silicates, catapleiite and elpidite in a peralkaline granite from the Ilímaussaq complex, south Greenland.
At Sams Creek a gold-bearing, peralkaline granite pophyry dyke intrudes Ordovician-Silurian metapelite and quartzite. The granite porphyry dyke has a thickness of up to 40 m, extends discontinuously for about 8 km, and intrudes thin lamprophyre dykes along its contacts. The granite dyke and gold-bearing sulphide and quartz-siderite veins within it …
At Sams Creek, a gold-bearing, peralkaline granite porphyry dyke, which has a 7km strike length and is up to 60m in thickness, intrudes camptonite lamprophyre dykes and lower greenschist facies ...
At Sams Creek, a gold-bearing, peralkaline granite porphyry dyke, which has a 7 km strike length and is up to 60 m in thickness, intrudes camptonite lamprophyre dykes and lower greenschist facies metapelites and quartzites of the Late Ordovician Wangapeka formation. The lamprophyre dykes occur as thin (< 3 m) slivers along the …
Peralkaline granites and pegmatites are a prime repository of REE and HFSE, critical raw materials. Although it is accepted that magmatic processes are fundamental in concentrating these metals, the role of hydrothermal fluids in concentrating and fractionating these elements remains unclear. This paper investigates the global …
The Crust. A.I.S. Kemp, C.J. Hawkesworth, in Treatise on Geochemistry, 2003 3.11.4.3.4 Relevance for crustal evolution. The average Padthaway suite A-type pluton of Turner et al. (1992a), together with metaluminous and peralkaline A-type granite samples from the LFB are plotted in Figure 5(d).The markedly enriched HFSE and REE contents are salient …
Hydrothermal metasomatism of a peralkaline granite pegmatite, Khaldzan Buragtag massif, Mongolian Altai; Complex evolution of REE-Nb minerals.pdf. Available via license: CC BY-NC-ND 4.0.
At Sams Creek, a gold-bearing, peralkaline granite porphyry dyke, which has a 7km strike length and is up to 60m in thickness, intrudes camptonite lamprophyre …
The Dimra Pahar Pluton is composed of arfvedsonite ± aegirine - alkali-feldspar granites with homophanous and mylonitic features. The pluton was emplaced along a regional shear zone during the post-collisional stage of the orogeny. Arfvedsonite and aegirine crystallized after alkali feldspar and quartz. The rocks are slightly peraluminous …
2011. Experimental modeling of the transformation of H 2 O-CO 2 -CH 4 inclusions during isobaric cooling and isothermal compression. OV Vasyukova, VI Fonarev. Geochemistry International 44, 1170-1180., 2006. 9. 2006. Articles 1–20. Research Associate, McGill University - Cited by 829 - Ore geology.
Interestingly, the mixing hyperbola (R 2 = 0.85) of Gd N /Yb N (0.5–1.2) and Zr/Sm (50–240) for peralkaline granites indicate interaction between magmas and alkali …
The Khaldzan-Buregtey rare metal (Nb, Zr, REE, etc.) deposit in peralkaline granitoids is located in western Mongolia, 45 km northeast of the town of Kobdo. The deposit, which was discovered by the authors, is composed of dome-shaped stocks of rare metal peralkaline granite covering 0.85 km and represents the late plutonic phases of …
By extraction of incompatible elements such as Nb, Ta, W, and Sn from the cumulate residuum (e.g., the main granite body), the peralkaline melt fractions may form rare-metal deposits of the Zr–Hf–Nb–Ta–REE type. The high concentration of F is responsible for complexing the REEs and other high field strength elements, indicated …
The crystal structures of seven sodic amphiboles from the Strange Lake peralkaline granite, on the Quebec–Labrador border, have been refined to R values of 1.3–1.7% using single-crystal MoKα X-ray data.Crystals used in the collection of the intensity data were subsequently analyzed by electron- and ion-microprobe methods.
The petrographic study shows the granite samples consist mainly of perthite, hornblende, plagioclase, quartz, alkali-feldspar, and biotite (Fig. 2a and b). To establish the formation time and origin of the alkaline-peralkaline granite, seven granite samples representing the El Dair complex were collected for analyses.
A characteristic of peralkaline A-type granite is their natural high concentration in high-field-strength elements (HFSE, i.e. Zr, Hf, Ta, Nb, Th, Ti, Y and REE). ... mesothermal gold deposits are ...
Peralkaline granite. Granite is a medium-tocoarse-grained acid igneous rock with essential quartz (>20%) and feldspar, where alkali feldspar constitutes between 100 and 35% of the feldspars, and minor mafic minerals. Hornblende and biotite are the commonest mafic minerals, however, muscovite is also frequently encountered.
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