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30 lat mössbauerowskich badań meteorytów w Polsce

Gałązka-Friedman Jolanta, Jakubowska Martyna, Woźniak Marek, Brzózka Katarzyna, Grabias Agnieszka, Szopa Krzysztof

Postępy Fizyki

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2024

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T. 75, z. 2

3--16

PL

Spektroskopia mössbauerowska57 Fe jest jedną z najczęściej stosowanych metod badania meteorytów. Początek badań mössbauerowskich w Polsce związany jest z meteorytem Baszkówka, który spadł 25.08.1994 w okolicach Warszawy. W artykule przedstawione są niektóre wyniki 30-letnich mössbauerowskich badań meteorytów, otrzymane przez polski zespół badawczy. Do najważniejszych osiągnięć naszej grupy należy opracowanie metody klasyfikacji chondrytów zwyczajnych, które stanowią 87% meteorytów znajdowanych na powierzchni Ziemi. Metoda ta nazwana przez nas metodą 4M (od angielskojęzycznych terminów meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis, Mahalanobis distance) jest metodą ilościową, wykorzystującą pewne systematyczności w mössbauerowskich widmach chondrytów zwyczajnych.1 Podstawowym elementem metody 4M jest baza danych, która w tej chwili składa się z wyników mössbauerowskich pomiarów 87 próbek meteorytów. W artykule omówione są również nowe fazy mineralne zidentyfikowane w meteorycie Morasko. Podano przykłady zastosowania spektroskopii mössbauerowskiej do odróżniania próbek meteorytopodobnych od prawdziwych meteorytów. Omówiliśmy też nasze plany związane z badaniem mechanizmu powstawania chondrytów zwyczajnych oraz z zastosowaniem spektroskopii mössbauerowskiej w przyszłych misjach kosmicznych. Te ostatnie problemy będą rozwiązywane we współpracy z czeską pracownią mössbauerowską Uniwersytetu Palackiego w Ołomuńcu.

EN

57Fe Mössbauer spectroscopy is one of the most commonly used methods for studying meteorites. The beginning of Mössbauer research in Poland is associated with the Baszkówka meteorite, which fell on 25 August 1994 near Warsaw. The article presents some of the results of 30 years of Mössbauer studies of meteorites by the Polish team. One of the most important achievements of our group is the development of a classification method of ordinary chondrites, which constitute 87% of meteorites found on the earth’s surface. This method, which we call the 4M method (meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis, Mahalanobis distance), is a quantitative method that uses certain systematicity in the Mössbauer spectra of ordinary chondrites. The basic element of the 4M method is the database, which currently consists of the results of Mössbauer measurements of 87 meteorite samples. The article also discusses the new mineral phases identified in the Morasko meteorite. Examples of the use of Mössbauer spectroscopy to distinguish meteorite-like samples from real meteorites are given. Our research plans related to the study of the formation mechanism of ordinary chondrites and the use of Mössbauer spectroscopy in future space missions are also discussed. The latter issues will be undertaken in cooperation with the Mössbauer laboratory at Palacký University in Olomouc (Czech Republic).

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Datowanie apatytów z żył kwarcowo-chlorytowo-apatytowych w fyllitach z Podmąchocic (Góry Świętokrzyskie)

Salwa Sylwester, Szopa Krzysztof

Przegląd Geologiczny

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2023

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Vol. 71, nr 5

298--300

EN

Metamorphic rocks of greenstone facies (phyllites) have been discovered quite recently in the Łysogóry region of the Holy Cross Mountains. The following minerals predominate in the mineral composition of these rocks: bright mica (sericite), quartz, chlorites, rutile, pyrophyllite, xenotime, pyrite, tourmaline, apatite and monacite, while chalcopyrite, sphalerite and galena are also present in mineral veins. The phyllites from Podmąchocice are intensely tectonically deformed, while their metamorphism displays a syndeformation character. The age of the tectonic-metamorphic processes has been initially estimated based on their relation to the silicification process. The phyllites are cut by numerous hydrothermal mineral veins, including quartz-chlorite-apatite ones. These veins occur as small post-tectonic and syntaxial forms, a few centimetres long and up to 1 cm thick. In the central parts of the veins, apatite forms colourless crystals, up to 1 mm long and up to 0.1mm thick. The age of the apatites was determined by means of the laser ablation system combined with the mass spectrometer. The results of isotopic measurements were reduced using the “Vizual Age” reduction program. The U-Pb age has been estimated to ~389 ± 18 Ma (upper intercept) that points to the maximum Devonian age (Eifelian/Givetian) of formation of the quartz-apatite veins. This is the first dating that point sto hydro thermal activity of th is age in the study area. As the veins cut discordantly the metamorphic rocks, the metamorphism itself may be older than the apatite age.

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Neoproterozoic ophiolite exotic blocks in the Outer Western Carpathians, southern Poland : a record of the fast ocean-floor cooling and alterations

Gawęda Aleksandra, Szopa Krzysztof, Waśkowska Anna, Golonka Jan, Krzykawski Tomasz, Kalinichenko Tatiana

Geological Quarterly

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2023

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Vol. 67, No. 1

art. no. 9

EN

Ophiolitic blocks, represented by metagabbro and serpentinite containing relict pyroxene, olivine, baddeleyite, zirconolite, Ni-pyrite and pyrrhotite, were found as exotic blocks in an olistostrome in the Magura Nappe, Outer Western Carpathians. The geochemical and isotopic features of the blocks suggest they represent mantle-derived rocks, with within-plate geochemistry signatures, modified by subduction, with lithospheric mantle input. A U-Pb apatite cooling age (614 ±3 Ma) is within age uncertainty of a published U-Pb zircon magmatic crystallization age (~614 Ma) implying rapid post-crystallization cooling. Pervasive alteration with replacement of primary minerals by low-temperature assemblages is observed in all rock fragments and is interpreted as contemporaneous with shearing. The secondary mineral assemblages and temperature modelling allow the interpretation that the pervasive ocean-floor metamorphism is the alteration in these meta-mafic rocks. These ophiolitic fragments can be linked to the Neoproterozoic break up of Rodinia/Pannotia.

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Silesian Ridge in the light of petrological analyses and LA-ICP MS U-Pb analyses of the cohesive debrites from the Istebna Formation (Silesian Nappe, Outer Western Carpathians, Poland)

Szczuka Monika, Gawęda Aleksandra, Waśkowska Anna, Golonka Jan, Szopa Krzysztof, Chew David, Drakou Foteini

Geological Quarterly

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2022

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Vol. 66, No. 2

art. no. 20

EN

Exotic clasts present in flysch deposits of the Western Outer Carpathians enable investigation and reconstruction of the eroded crystalline basement of the Silesian Ridge. The flysch rocks of the Istebna Formation (Jasnowice Member: Paleocene) in the Silesian Nappe contain magmatic and metamorphic clasts derived from the Silesian Ridge basement. The crystalline rock fragments acquired from cohesive debrites were analyzed petrographically and geochemically, and zircon and rutile crystals were subject to LA-ICP-MS U-Pb dating. Granitoid clasts yielded Meso-Variscan U-Pb zircon ages (325.7 and 330.6 Ma), with older (Neoproterozoic to Paleoproterozoic) inherited cores and eNd330 = –12.0 (TDM age of 1.98 Ga). The orthogneiss clast yielded a protolith age of 1635 Ma and fingerprint of thermal reworking at ~288 Ma. Zircon crystals from the detrital clasts yielded similar U-Pb zircon ages to the granitoid clasts (311.5 to 391 and 331 Ma). The rutile crystals from sandstone yielded concordia age of 344.7 Ma. Zircon crystals from paragneiss, interpreted as a granitoid envelope, yielded 238U/206Pb ages between 557 and 686 Ma and include an inherited core of age ~1207.4 ±33.8 Ma. Age data from exotic clasts and the detrital zircon and rutile fraction suggest the core part of the Silesian Ridge was a Neoproterozoic to Mesoproterozoic envelope intruded by Meso-Variscan granitoid plutons.

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Ancylite-(Ce) from quartz-calcite-chlorite veins in phyllite of the Opava Mountains (SW Poland)

Janeczek Janusz, Szopa Krzysztof, Fabiańska Monika

Geological Quarterly

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2020

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Vol. 64, No. 3

801--806

EN

Ancylite-(Ce) occurs in quartz-calcite-chlorite veins crosscutting the foliation of phyllite in the Dewon Quarry in the foothills of the Opava Mountains of the eastern Sudetes, south-west Poland. Irregularly shaped grains of ancylite are up to 67 μm long and 22 μm wide. The compositional range of ancylite, determined by electron microprobe, is expressed by the empirical formula: (Sr0.65-0.55Ca0.19-0.14Fe0.03-0.00)∑0.87-0.69 (Ce0.58-0.50Nd0.26-0.22La0.26-0.21Pr0.06-0.05Sm0.05-0.04Gd0.07-0.03Dy0.01-0.00)∑1.29-1.05 (CO3)2(OH1.07-0.99F0.22-0.0.06)∑1.29-1.05· 0.95-0.93H2O. Ancylite crystallized directly from CO2-rich hydrothermal solutions as the last mineral in the veins following precipitation of calcite. The solution temperature, estimated using various chlorite geothermometres, was in the range of 260-340°C.

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Polskie mołdawity : obecny stan wiedzy i perspektywy nowych znalezisk

Szopa Krzysztof, Brachaniec Tomasz, Karwowski Łukasz

Przegląd Geologiczny

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2019

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Vol. 67, nr 8

662--667

EN

The first Polish moldavites were discovered in 2012. This paper is a summary of the distribution and inventory of these Polish tektites. Up to the present, 28 moldavites have been described from seven different sandpits. These moldavites were deposited in the upper Miocene fluvial deposits of the Gozdnica Formation, as well as in the Pleistocene river terraces. Apart from a typical bottle green colour, moldavites also have other diagnostics features for this class of tektites, such as the presence of bubbles, inclusions oflechatelierite, as well as the same, homogeneous chemical composition. Fluvial redeposition was interpreted as the main process which determined moldavite distribution. Despite the most recent find of one moldavite specimen in Bielawy, all of these specimens indicate both Lusatian as well as sub-strewn Czech fields as their supply area.

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Continuous magma mixing and cumulate separation in the High Tatra Mountains open system granitoid intrusion, Western Carpathians (Poland/Slovakia): a textural and geochemical study

Gawęda Aleksandra, Szopa Krzysztof, Włodyka Roman, Burda Jolanta, Crowley Quentin, Sikorska Magdalena

Acta Geologica Polonica

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2019

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Vol. 69, no. 4

549--570

EN

In this study the formation of the polygenetic High Tatra granitoid magma is discussed. Felsic and mafic magma mixing and mingling processes occurred in all magma batches composing the pluton and are documented by the typical textural assemblages, which include: mafic microgranular enclaves (MME), mafic clots, felsic clots, quartz-plagioclase-titanite ocelli, biotite-quartz ocelli, poikilitic plagioclase crystals, chemically zoned K-feldspar phenocrysts with inclusion zones and calcic spikes in zoned plagioclase. Geochemical modelling indicates the predominance of the felsic component in subsequent magma batches, however, the mantle origin of the admixed magma input is suggested on the basis of geochemical and Rb-Sr, Sm-Nd and Pb isotopic data. Magma mixing is considered to be a first-order magmatic process, causing the magma diversification. The cumulate formation and the squeezing of remnant melt by filter pressing points to fractional crystallization acting as a second-order magmatic process.