The Seve Nappe Complex exposed in the Kittelfjäll area of the northern Scandinavian Caledonides comprises a volcano-sedimentary succession representing the Baltica passive margin, which was metamorphosed during the Iapetus Ocean closure. Garnet amphibolites, together with their host migmatitic paragneisses, record a potential (U)HP event followed by decompression-driven migmatization. The garnet amphibolites were originally thought to represent retrogressively altered granulites. The petrological and geochemical features of a studied garnet amphibolite allow for speculation about a peridotitic origin. Zirconium (Zr) content in rutile inclusions hosted in garnet in paragneisses points to near-peak temperatures between 738 °C and 780 °C, which is in agreement with the c. 774 °C obtained from the matrix rutile in the garnet amphibolite. The matrix rutile in multiple paragneiss samples records temperatures below 655 °C and 726 °C. Whereas the LA-ICP-MS U-Pb dating of zircon cores revealed the age spectrum from Paleoproterozoic to early Paleozoic, suggesting a detrital origin of zircon cores in paragneisses, the metamorphic zircon rims show an Early Ordovician cluster c. 475–469 Ma. Additionally, zircon cores and rims from the garnet amphibolite yielded an age of c. 473 Ma. The REE patterns of the Caledonian zircon rims from the paragneisses show overall low LREE concentrations, different from declining to rising trends in HREE (LuN/GdN = 0.49–38.76). Despite the textural differences, the cores and rims in zircon from the garnet amphibolite show similar REE patterns of low LREE and flat to rising HREE (LuN/GdN = 3.96–65.13). All zircon rims in both lithologies display a negative Eu anomaly. Hence, we interpret the reported ages as the growth of metamorphic zircon during migmatization, under granulite facies conditions related to exhumation from (U)HP conditions.
During the cokemaking process, a significant amount of mercury occurring in a coal blend is released to the atmosphere. One of the ways of reducing this emission is to reduce mercury content in a coal blend. This could be obtained through the coal washing process. The optimization of this process requires the knowledge of mercury occurrence in coal, especially in its inorganic constituents. A qualitative analysis of mercury occurrence in the inorganic constituents of Polish coking coals was performed using an electron probe microanalyzer (EPMA). For that purpose, selected samples of rejects and middling products derived from the washing process in dense media separators and jig concentrators were examined. The obtained results have confirmed a strong connection between mercury occurrence and the presence of sulfides (pyrite, marcasite, and chalcopyrite) in Polish coking coals. Significant amounts of mercury were also noticed for barite, siderite, and aluminosilicates. The highest value of mercury content, at the level of 0.100%, was obtained for marcasite. For the analyzed coals, the effectiveness of mercury removal in the washing process was determined by the forms of pyrite occurring in coal. The highest values of effectiveness of mercury removal were obtained in the case of coals for which the large framboidal pyrite aggregates with chalcopyrite overgrowths were noticed. It was also found that middling products were characterized by the occurrence of the Hg-rich overgrowths of pyrite on organic matter. To achieve a significant reduction in mercury content in clean coal, it is necessary to develop an effective method of removing this form of pyrite from hard coal.
Two tourmaline samples occurring in quartz veinlets, which crosscut an amphibolite body at the Budniki camp near the Kowary town, in the south-west part of the Karkonosze Mountains (SW Poland), were studied through microprobe and single crystal X-ray diffraction. Samples were extracted from core and rim regions of crystals with a concentric zoning, respectively.Chemical and structural data revealed that the core tourmaline is characterized by a draviteoxy-dravite composition, with formula: X (Na0.82Ca0.07K0.01Sr0.010.09)Σ1 Y (Mg1.73Fe 2+ 0.81Fe 3+ 0.41Ti0.04V0.01)Σ3 . Z (Al5.85Fe 3+ 0.15)Σ6 ( T Si6O18) (BO3)3 (OH)3 W (OH0.50O0.50)Σ1 and unit cell parameters a = 15.97377(14) Å and c = 7.22644(7) Å. The rim part of the crystals has a magnesio-lucchesiite composition, described by the formula: X (Ca0.49Na0.41K0.04Sr0.020.04)Σ1 Y (Mg1.87Fe 2+ 0.95Ti0.15Fe 3+ 0.02V0.02)Σ3 Z (Al5.49Fe 3+ 0.51)Σ6 (BO3)3
A geochemically primitive, moderately fractionated, LCT pegmatite from Lutomia (Góry Sowie Block, SW Poland) has been characterized in respect of the primary and secondary phosphate assemblages. The pegmatite crystallized from anatectic granitic magmas mobilized by M 2-3 metamorphism at ~370-380 Ma. Three phosphate assemblages had a different origin: (1) the primary, magmatic one [graftonite-(I)-beusite-(I) + triphylite ± sarcopside], (2) a secondary, metasomatic one [Ca-rich graftonite-(II) -Ca-rich beusite-(II) + wolfeite/triploidite/stanĕkite + hagendorfite/alluaudite + kryzhanovskite ± a Ca-bearing phosphate close to ferromerrillite + fluorapatite], and (3) a secondary, hydrothermal and weathering one [ferrisicklerite ± heterosite + phosphoferrite-kryzhanovskite + ludlamite + vivianite ± hureaulite + earlshannonite-whitmoreite + strunzite-ferrostrunzite + beraunite + dufrénite + jahnsite-(CaMnFe), -(CaMnMn) and -(MnMnMn) + landesite + fairfieldite + Mn 2+ -bearing hydroxyapatite]. The magmatic assemblage resulted from the breakdown of a primary, high-T, Ca-and Li-enriched graftonite-like phase. It was induced by cooling and elevated incompatible Ca, Na, Li and F concentrations. The metasomatic assemblage reflects the destabilization of the magmatic phosphates and their Ca-and Na-metasomatism by a high-T fluid connected with a PO 4 -bearing melt, which previously had evolved along with graftonite-(I)-beusite-(I). The assemblage of secondary, hydrothermal and weathering, phosphates was a result of lower T alteration by hydrothermal fluids and meteoric water by both topotactic Fe and Mn oxidation as well gradual hydration and Fe oxidation. Taken together, the Lutomia pegmatite has been compared to the phosphate-bearing pegmatite at Michałkowa and the mixed NYF + LCT, PO 4 -poor pegmatitic system of Piława Górna.Keywords: phosphate-bearing pegmatite, LCT anatectic pegmatite, Lutomia, Poland Received: 16 October 2013; accepted: 25 November 2014; handling editor: Milan Novák The online version of this article (doi: 10.3190/jgeosci.185) contains supplementary electronic material.Moreover, Łodziński and Sitarz (2009) studied graftonite and sarcopside from Michałkowa.The aim of this paper is a description of the Lutomia pegmatite, as the currently best representative of phosphate pegmatitic mineralization in the GSB, and an evaluation of its relationships to the other important pegmatites in the unit. Particular attention is being paid to textural relations and chemical compositions of the minerals that reflect the geochemical evolution of the pegmatiteforming melts.
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