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Wyszukujesz frazę "ordinary chondrites" wg kryterium: Temat


Wyświetlanie 1-15 z 15
Tytuł:
Próby klasyfikowania chondrytów zwyczajnych przez zastosowanie spektroskopii mössbauerowskiej
Attempts of classification of ordinary chondrites by application of Mössbauer spectroscopy
Autorzy:
Gałązka-Friedman, Jolanta
Woźniak, Marek
Duda, Przemysław
Jakubowska, Martyna
Bogusz, Patrycja
Karwowski, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/1032381.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Mössbauer spectroscopy
classification of meteorites
ordinary chondrites
Opis:
Mössbauer spectra of equilibrated ordinary chondrites consist of two sextets due to magnetically ordered iron present in metallic phases and troilite and two doublets due to paramagnetic iron present in olivines and pyroxenes. The Mössbauer spectral areas of the different mineralogical phases in meteorites are proportional to the number of iron ions present in olivines, pyroxenes, metallic phase and troilite. This property of Mössbauer spectra was the basis for constructing various methods for the classification of ordinary chondrites. Review of these methods will be presented.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 23-28
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
NWA 14360 – Nowy meteoryt z Nigru
A new meteorite from Niger: NWA 14360
Autorzy:
Karwowski, Łukasz
Szopa, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/2034032.pdf
Data publikacji:
2022-03
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
ordinary chondrites
NWA 14360
meteorite
meteorites classification
Opis:
The new meteorite was bought as one single stone in 2019 from a dealer in Niger by Tomasz Jakubowski. The meteorite has fusion crust. It contains chondrules of different types with dominance of barred olivine chondrules, with diameter to 1.5 mm. Px and Ol are 78.1 vol%. of the meteorite mass. Pl is up 11.8 vol%. Average fayalite content is 24.93. Metallic phases are 3.0 vol%. Troilite is up to 5.9 vol%. Spinel (Cr-spinel) is up to 0.9 vol%. Average content of the secondary Fe-rich minerals (e.g. hydroxides) is 0.4 vol%. Feldspar composition is: Ab80.2Or5.0An14.8. Mean content of Al2O3, MgO and TiO2 in chromium spinel is 6.70 wt%, 2.05 wt% and 2.02 wt%, respectively. Metal phases are kamacite and tetrataenite. The kamacite has a Ni content in the range 5.83–6.81 wt%, while the Co content is in the range 0.39 to 0.56 wt%. Tetrataenite is has Ni content from 49.68 to 50.46 wt%, and Co up to 0.05 wt%. High-Ca monoclinic pyroxene, similar to diopside, is very rare. Accessory minerals are: chlorapatite and merrylite. Base on chemistry and petrography, the meteorite is classified as ordinary chondrite (L5). The main mass, a 9190 g specimen, is in Krzysztof Socha private collection. Small fragments with the total mass 71 g are stored in Museum of Earth Sciences (catalogue no: WNoZ/Mt/110) at University of Silesia in Katowice, Poland. 39 g was used for thin-section preparation and spectroscopic investigation (Mössbauer spectroscopy).
Źródło:
Acta Societatis Metheoriticae Polonorum; 2022, 13; 47-59
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Osłabianie promieniowania gamma w chondrytach zwyczajnych
Gamma rays attenuation in ordinary chondrites
Autorzy:
Kaczmarzyk, Marcin
Powiązania:
https://bibliotekanauki.pl/articles/1032387.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
ISRU
asteroids
astronautics
cosmic rays
gamma rays attenuation
ordinary chondrites
Opis:
This paper elaborates on gamma rays attenuation in ordinary chondrites. Highly penetrating gamma radiation is emitted as a result of inelastic collisions of ultra-high energy cosmic particles with bulk matter, such as spacecraft hulls. Resources mined from Solar System small bodies may present an alternative construction material for spacecraft cosmic rays shields, which explains research on ionizing radiation attenuation in meteorites. A custom-made, shielded research workstation was constructed to analyse ionizing radiation absorption in pulverized materials. Using the workstation, gamma rays attenuation experiment was performed on pulverized ordinary chondrite – a meteorite originating from S-type asteroid. The experiment resulted in obtaining gamma ray mass attenuation coefficient of S-type chondritic asteroid matter. Obtained results were analysed and final conclusions were formulated. Per unit mass, ordinary chondrites exhibit better gamma rays attenuation properties than any radiation shielding material contemporarily used in astronautics.
W niniejszej pracy poruszono zagadnienie pochłaniania promieniowania gamma w materiale budującym meteoryty należące do grupy chondrytów zwyczajnych, które pochodzą z planetoid typu S. Wysoce przenikliwe promieniowanie gamma powstaje w przestrzeni kosmicznej m.in. jako efekt oddziaływania pierwotnego promieniowania kosmicznego z ośrodkami materialnymi. Materiał pozyskany z małych ciał Układu Słonecznego może stanowić alternatywny budulec ciężkich osłon radiacyjnych statków kosmicznych, co uzasadnia prowadzenie badań nad pochłanianiem promieniowania jonizującego w meteorytach. Opisano tu eksperyment, do celów którego wykonano autorskiej konstrukcji stanowisko badawcze do analizy pochłaniania promieniowania jonizującego w materiałach sypkich. Przy pomocy tego stanowiska, wykorzystując radioaktywny izotop 60Co, określono masowy współczynnik absorbcji promieniowania gamma w sproszkowanym chondrycie zwyczajnym, a otrzymany wynik porównano z wartością obliczoną teoretycznie. W pracy przeprowadzono szczegółową analizę uzyskanych wyników i sformułowano wnioski płynące z przeprowadzonego eksperymentu. Na jednostkę masy, chondryty zwyczajne lepiej osłabiają promieniowanie gamma niż jakiekolwiek materiały osłonowe stosowane obecnie w astronautyce.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 40-50
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mössbauerowskie badania meteorytu Kuźnica
Mössbauer studies of Kuźnica meteorite
Autorzy:
Jakubowska, Martyna
Woźniak, Marek
Bogusz, Patrycja
Karwowski, Łukasz
Gałazka-Friedman, Jolanta
Duda, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/1830270.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
4M method
Kuźnica
Mössbauer spectroscopy
Rumanová ordinary chondrites
meteorites
Opis:
Kuźnica meteorite was found in summer 2008 by an inhabitant of Częstochowa in the village of Kuźnica (Poland, voivodeship: Łódź, county: Pajęczano) in Poland. The finder, who is a passionate and collector of interesting stones, shared his find with the world only after a few years in the autumn of 2018. The found meteorite with a mass of 2.14 kg is an ordinary chondrite type H5. The degree of weathering on the surface is W2, inside W1. Currently, the meteorite is represented by 3 parts and two thin plates. The main mass is 2.037 kg, fragments are 13.7 g and 5.81 g. The found object was officially classified as a meteorite on 22th of November 2020. In this paper, we present the results of the Kuźnica meteorite measurements obtained by using the Mössbauer spectroscopy method. Mössbauer measurements of Kuźnica were performed at room temperature. The experimental spectrum was elaborated with “Recoil” program. Nine mineralogical phases were identified in the obtained Mössbauer spectrum: two doublets associated with olivine, two doublets associated with pyroxene, sextet associated with troilite, sextet associated with metallic phase identified as kamacite, doublet associated with iron hydroxides and two sextets associated with oxyhydroxides. The presence of a metallic phase or troilite in the test sample is convincing evidence of its extraterrestrial origin. These are mineralogical phases that can only arise in space conditions. Mössbauer spectroscopy allows for unambiguous identification of these mineralogical phases. In the standard 4M method, we use four basic phases to determine the type of ordinary chondrite: olivine, pyroxene, troilite and metallic phase, and we choose specimens in which the content of weathered phases does not exceed 7%. The Kuźnica meteorite is heavily weathered. The content of weathered phases is as much as 36.4%. Secondary minerals are a breakdown product of the metallic phase and to a lesser extent of the sulphide phase. Due to the strong weathering of the Kuźnica meteorite, we can modify the 4M method using only two basic phases: olivine and pyroxene. The analysis of the location of the Kuźnica meteorite on the figure of pyroxene vs. olivine dependence shows that it is ordinary chondrite type H. In this paper, the influence of the loss of the metallic and sulphide phases on the position of the Kuźnica meteorite on the figure of pyroxene/olivine vs. (pyroxene+metallic phase/(olivine+troilite)) was also checked. Weathering processes significantly transform many minerals. The resulting compounds often have parameters difficult to identify. However, difficulties in identifying secondary phases and their origins should not prevent an attempt to determine the type of meteorites using the 4M method.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2021, 12; 31-40
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wstępne wyniki pomiarów moessbauerowskich meteorytu Shisr 176
Moessbauer studies of Shisr 176 meteorite – preliminary results
Autorzy:
Gałązka-Friedman, Jolanta
Szlachta, Karol
Woźniak, Marek
Powiązania:
https://bibliotekanauki.pl/articles/1032961.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Baszkówka meteorite
Moessbauer spectroscopy
Shisr 176
Sołtmany meteorite
meteorites
ordinary chondrites
Opis:
In Moessbauer spectrum of Shisr 176 meteorite four main iron-bearing minerals were identified: olivine, pyroxene, kamacite and troilite. Iron distribution among this minerals in Shris meteorite is similar to Sołtmany meteorite and different than in Baszkówka meteorite. As these three meteorites are type L ordinary chondrites this comparison might be used as a basis of a new criterion of the classification of the meteorites.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2013, 4; 39-45
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania mössbauerowskie trzech chondrytów zwyczajnych typu H i trzech chondrytów zwyczajnych typu LL – wyznaczanie niepewności powierzchni spektralnych
Mössbauer studies of three ordinary chondrites type H and three ordinary chondrites type LL – uncertainty of the determination of spectral areas
Autorzy:
Jakubowska, Martyna
Buczek, Aleksandra
Gwiździel, Katarzyna
Djellouli, Adam
Nowak, Filip
Woźniak, Marek
Gałązka-Friedman, Jolanta
Karwowski, Łukasz
Duda, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/1032384.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Bassikounou
Buzzard Coulee
Kilabo
Mössbauer spectroscopy
NWA 4841
NWA 6287
Zag
ordinary chondrites
Opis:
Mössbauer 57Fe measurements of three ordinary chondrites type H and of three ordinary chondrites type LL were performed at room temperature. The spectral areas were fitted using the “Recoil” program (Lagarec i in. 1998). Fitting was repeated three times which allowed us to determinate the differences between the results of fits performed by different persons.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 34-39
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
O przewodności cieplnej meteorytu Jezersko
The thermal conductivity of the Jezersko meteorite
Autorzy:
Szurgot, Marian A.
Powiązania:
https://bibliotekanauki.pl/articles/2145826.pdf
Data publikacji:
2021
Wydawca:
Instytut Nafty i Gazu - Państwowy Instytut Badawczy
Tematy:
meteoryt Jezersko
chondryty zwyczajne
przewodność cieplna
Jezersko meteorite
ordinary chondrites
thermal conductivity
Opis:
Praca prezentuje wyniki przewidywań teoretycznych przewodności cieplnej (K) meteorytu Jezersko, sklasyfikowanego jako chondryt zwyczajny H4. Przewidywania oparto na wybranych modelach skał i różnych zależnościach teoretycznych i empirycznych. Wykorzystano skład modalny chondrytu Jezersko ustalony przez autora oraz literaturowe dane o przewodności cieplnej minerałów składowych meteorytu i jego porowatości (P). Stosując wymienione metody, określono przewodność cieplną szkieletu ziarnowego meteorytu i jego globalną przewodność cieplną, wykorzystując także przewidywane wartości dyfuzyjności cieplnej (D). Wyniki potwierdzają znane prawidłowości dotyczące skał ziemskich i meteorytów, że współczynnik porowatości skały i materia wypełniająca pory silnie wpływają na przewodność cieplną. Model średniej geometrycznej przewiduje dla szkieletu ziarnowego meteorytu Jezersko wartość przewodności cieplnej 4,35 W m−1 K−1, a średnia z dwóch modeli warstwowych: modelu średniej harmonicznej i modelu średniej arytmetycznej wartość 4,9 W m−1 K−1 dla temperatury 300 K. Globalna przewodność cieplna meteorytu Jezersko (K) według modelu średniej geometrycznej w temperaturze 300 K wynosi 2,6 W m−1 K−1 dla ciśnienia powietrza 1 atm, a 1,0 W m−1 K−1 dla próżni. Model Hashina–Shtrikmana przewiduje wartości K: 2,4 W m−1 K−1 i 1,9 W m−1 K−1, model Clausiusa–Mossottiego – wartości: 2,2 W m−1 K−1 i 1,9 W m−1 K−1, natomiast modele warstwowe skał – wartości: 2,1 W m−1 K−1 i 2,0 W m−1 K−1 dla temperatury 300 K i powietrza pod ciśnieniem 1 atm oraz dla próżni. Zależność pomiędzy przewodnością cieplną i porowatością wskazuje średnią wartość K dla meteorytu Jezersko dla próżni: 1,18 W m−1 K−1, a zależność pomiędzy przewodnością cieplną i dyfuzyjnością cieplną wskazuje wartość K: 1,12 W m−1 K−1 dla zakresu 200–300 K dla próżni, a w przypadku powietrza pod ciśnieniem normalnym wartość: 2,57 W m−1 K−1. Średnia wartość przewodności cieplnej chondrytu Jezersko dla wszystkich przewidywań wynosi w przypadku temperatury ~300 K i ciśnienia powietrza 1 atm: 2,45 ± 0,30 W m−1 K−1, a w przedziale temperatur 200–300 K i próżni: 1,40 ± 0,40 W m−1 K−1. Przewidywane wartości globalnej przewodności cieplnej meteorytu Jezersko dla powietrza i próżni są w zakresie wartości ostatnio prezentowanych przez Soini i in. (2020) dla grupy H4 chondrytów zwyczajnych: 2,8 ± 0,6 W m−1 K−1, wartość średnia K przy wypełnieniu porów przez powietrze pod ciśnieniem 1 atm, oraz 1,9 ± 1,0 W m−1 K−1, wartość średnia K dla zakresu temperatur: 200–300 K, gdy ośrodkiem wypełniającym pory jest próżnia.
The thermal conductivity (K) of Jezersko H4 meteorite was predicted by various models of rocks, using literature data on the chemical composition, porosity (P), and by relationships between thermal conductivity and porosity, and between thermal conductivity and thermal diffusivity (D). The results confirm that the porosity of the chondrite and air pressure significantly affect thermal conductivity. The thermal conductivity of the chondrite skeleton/matrix predicted by the modal composition of the meteorite and by the geometric mean model is equal to 4.35 W m−1 K−1, and by arithmetic and harmonic mean models: 4.9 W m−1 K−1at 300 K. Bulk thermal conductivity of the meteorite predicted by the geometric mean model is equal to 2.6 W m-1 K-1 for air pressure of 1 atm, and 1.0 W m−1 K−1in vacuum at 300 K. The Hashin–Shtrikman model predicts the values: 2.4 and 1.9 W m−1 K−1, the Clausius–Mossotti model: 2.2 and 1.9 W m-1 K-1, and the mean of two-layer models: 2.1 and 2.0 W m−1 K−1 at 300 K, for air pressure of 1 atm, and in vacuum, respectively. The relationships between thermal conductivity and porosity based on experimental data for ordinary chondrites indicate a mean K value for bulk thermal conductivity of the Jezersko meteorite in vacuum: 1.18 W m−1 K−1, and between thermal conductivity and thermal diffusivity the mean value: 1.12 W m−1 K−1at 200–300 K. The mean value for all predictions for bulk thermal conductivity of the meteorite for air at 1 atm is equal to 2.45 ± 0.30 W m−1 K−1 (range: 2.0–2.9 W m−1 K−1) at 300 K, and in vacuum: 1.40 ± 0.40 W m−1 K−1 (range: 0.95–2.0 W m−1 K−1) at 200–300 K. Predicted values of bulk thermal conductivity of the Jezersko meteorite, for air and in vacuum, are in the range of values recently reported by Soini et al. (2020) for the H4 group of chondrites: 2.8 ± 0.6 W m−1 K−1, mean K for air at 1 atm, and 1.9 ± 1.0 W m−1 K−1 mean K value in vacuum at 200–300 K.
Źródło:
Nafta-Gaz; 2021, 77, 1; 10-19
0867-8871
Pojawia się w:
Nafta-Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Planimetrowanie ziaren FeNi jako metoda ustalenia stopnia wietrzenia W0–W4 chondrytów zwyczajnych
FeNi grains planimetry as a method to establish weathering grade W0–W4 of ordinary chondrites
Autorzy:
Przylibski, Tadeusz A.
Łuszczek, Katarzyna
Blutstein, Konrad
Powiązania:
https://bibliotekanauki.pl/articles/1033132.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
FeNi alloy weathering
Wlotzka scale
meteorite
ordinary chondrite
ordinary chondrite weathering
ordinary chondrites weathering scale
weathering grade
Opis:
Wlotzka scale (Wlotzka 1993) is commonly used to determine the weathering grade of ordinary chondrites. The scale is descriptive and based mostly on a subjective assessment of researcher. In this paper authors define a new, quantitative method to establish the W0–W4 weathering grade, which is based on planimetry of FeNi grains. Results of planimetry are compared with average content of FeNi metal in unweathered chondrites from the same group. Weathering grade estimated by this method are consistent with, or slightly different from the official one determined in classification, what proves the efficacy of the proposed method. Moreover, the method was applied to define weathering grade of meteoritic samples not classified so far: Pułtusk (W2), Thuathe (W2), Gao-Guenie (W2/W3), NWA 5205 (W3), NWA 4505 (W3), NWA 5296 (W2).
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 111-120
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porównawcze badania mössbauerowskie meteorytów: Sołtmany (L6), Chelyabinsk (LL5) i Grzempy (H5)
Mössbauer comparative studies of the Sołtmany (L6), Chelyabinsk (LL5) and Grzempach (H5) meteorites
Autorzy:
Szlachta, Karol
Gałązka-Friedman, Jolanta
Woźniak, Marek
Powiązania:
https://bibliotekanauki.pl/articles/1033011.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Chelyabinsk (LL5)
Grzempy (H5)
Mössbauer spectroscopy
Sołtmany (L6)
classification of ordinary chondrites
meteorites
Opis:
Mössbauer studies of Chelyabinsk (LL5), Sołtmany (L6) and Grzempy (H5) show that the main iron bearing minerals in these meteorites are: Fe-Ni, troilite, olivine and pyroxene. Based on Mössbauer absorption area of different mineral phases, new set of parameters for classification of the ordinary chondrities were introduced. The most promising parameters are: the ratio of the olivine to pyroxene areas and the ratio of the silicate to metallic areas.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2014, 5; 115-120
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Od Baszkówki do Kuźnicy – 27 lat badań mössbauerowskich meteorytów w Polsce
From Baszkówka to Kuźnica – 27 years of Mössbauer studies of meteorites in Poland
Autorzy:
Gałązka-Friedman, Jolanta
Woźniak, Marek
Powiązania:
https://bibliotekanauki.pl/articles/2195003.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
meteorites
ordinary chondrites
Mössbauer spectroscopy
Baszkówka
Morasko
Kuźnica
Mt. Tazerzait
4M method
meteorites classifications
Opis:
The history, how the Mössbauer studies of meteorites began in Poland, was already described in our “Meteorites Odyssey… 20 years have passed”. One late afternoon (it was probably Spring 1995) I [Jolanta Gałązka-Friedman] was sitting in the Nonna Bakun’s office (at Banacha street) and we were talking about planet Mars. Suddenly Mr. Marian Stępniewski jumped to our room saying: We have a new Polish meteorite. It is called Baszkówka. Do you have any suggestion, how could we study this meteorite? Mössbauer spectroscopy – we both answered at the same time. And this is how it started, and it has been continued for the next quarter of a century. The first results of the Mössbauer studies of the Baszkówka meteorite were presented at the ISIAME conference in Johannesburg in 1996. In this paper we present the most important problems related to meteorites, which were investigated by us using Mössbauer spectroscopy. We will, however, show almost no formulas. We will try to explain everything by a method based on plots of Mössbauer spectra. We will try not to boast too much regarding our successes, but to explain also the problems that we were not able to resolve. While investigating the Baszkówka meteorite, we got most fascinated by troilite. We noticed that most of the laboratories determined the Mössbauer parameters of troilite incorrectly. They did not take into account the so-called theta angle, the value of which depends strongly on the number of vacancies and various additives. We thought that the theta angle may show us the parent body of the investigated meteorite. Unfortunately, this hypothesis turned up to be too difficult to defend. Then we studied Morasko meteorite and we discovered, by the comparison with Baszkówka meteorite Mössbauer spectra, and determined – up to now – not identified mineral phases present also in Morasko, such as pyrrhotite, daubréelite, taenite, tetrataenite, antitaenite and cohenite. In 2019 we published in MAPS a paper titled “Application of Mössbauer spectroscopy, multidimensional discriminant analysis and Mahalanobis distance for classification of equilibrated ordinary chondrites” (4M method), in which a new objective method for classification of ordinary chondrites is based on the knowledge of the Mössbauer spectra of the 4 main mineral phases present in the ordinary chondrites of H, L and LL type. Now we are working on the refinement of the 4M method enlarging our collaborative team by various foreign laboratories.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2023, 14; 31-55
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Odróżnianie próbek prawdziwych meteorytów od kamiennych próbek meteorytopodobnych – ważna rola spektroskopii mössbauerowskiej
Distinguishing between real and false meteorite samples – the important role of Mössbauer spectroscopy
Autorzy:
Bogusz, Patrycja
Gałązka-Friedman, Jolanta
Brzózka, Katarzyna
Jakubowska, Martyna
Woźniak, Marek
Karwowski, Łukasz
Duda, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/2034025.pdf
Data publikacji:
2022-03
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
ordinary chondrites
meteorites
Leoncin
Pu³tusk
Kheneg Ljouâd
Campos Sales
Julin
Mössbauer spectroscopy
4M method
Opis:
Four stony pieces were delivered to our laboratory for checking if they are fragments of meteorites: first sample (sample No. 1) was a fragment of a rock that fell near Leoncin in Poland, second sample (sample No. 2) was a fragment of a rock found also in Poland in the vicinity of Pultusk, third sample (sample No. 3) was a meteorite specimen bought on the meteorite exchange and fourth sample (sample No. 4) was a stone object whose decline was observed in Europe. We obtained mössbauer spectra of the delivered samples. The mössbauer spectrum of sample No. 1 is very similar to the spectrum of ordinary chondrite of type LL. Comparison of the mössbauer spectrum of sample No. 2 with mössbauer spectrum of Pu³tusk meteorite showed very large differences. In the spectrum of sample No. 3, a clear signal from iron-nickel alloy and troilite can be observed. These observations indicate that it is an object of extraterrestrial origin. Mössbauer spectrum of Sample No. 4 is similar to the spectrum of terrestrial magmatic rocks. Based on these spectrum we cannot clearly determine where the examined object comes from. This work demonstrates the usefulness of Mössbauer spectroscopy in recognizing samples that are fragments of meteorites.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2022, 13; 27-36
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ciepło właściwe i ciepło atomowe chondrytu Jezersko
Specific heat and atomic heat of the Jezersko chondrite
Autorzy:
Szurgot, Marian A.
Powiązania:
https://bibliotekanauki.pl/articles/2076001.pdf
Data publikacji:
2020
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
chondryt Jezersko
zwykłe chondryty
ciepło właściwe
ciepło atomowe
Jezersko chondrite
ordinary chondrites
specific heat
atomic heat
Opis:
Specific heat capacity of the Jezersko chondrite (H4, S2/3, W2) was predicted by a relationship between bulk density and heat capacity of meteorites Cp(dbulk). It was calculated that Cp(dbulk) is equal to 703±15 J/(kgK) at 300 K, and 529±15 J/(kgK) at 200 K. Its volumetric heat capacity is equal to 1.8±0.1 MJ/(m3K) at 200 K, and 2.3±0.1 MJ/(m3K) at 300 K, which is close to the room temperature value characteristic of stony meteorites (2.5 MJ/(m3K). The atomic heat of the Jezersko meteorite is 13.1±0.4J/(molK) at 200K and 17.4±0.4 J/(molK) at 300K. It was shown that mean atomic weight enables predicting room temperature values of specific heat capacity of ordinary chondrites, and the common mean atomic heat of ordinary chondrites is equal to 17.5±0.6 J/(molK) at 300 K.
Źródło:
Przegląd Geologiczny; 2020, 68, 1; 54--59
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Średni ciężar atomowy i gęstość ziaren chondrytu Jezersko (H4)
Mean atomic weight and grain density of Jezersko H4 chondrite
Autorzy:
Szurgot, Marian
Powiązania:
https://bibliotekanauki.pl/articles/1033134.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
H chondrites
Jezersko chondrite
grain density
iron to silicon ratio
mean atomic number
mean atomic weight
ordinary chondrites
weathering effects
Opis:
Mean atomic weight Amean of Jezersko (H4 S2(3) W2, find in 1992 in Slovenia) ordinary chondrite has been calculated using literature data on chemical composition of the meteorite (Miler et al. 2014) and using relationship between mean atomic weight and Fe/Si atomic ratio (Szurgot 2015c, d, e). It was shown that Jezersko’s Amean = 24.68, for composition without water. This value is close to the mean atomic weight of H chondrite finds (Amean = 24.80), and is somewhat smaller than Amean values for H4 chondrite falls (Amean = 25.09), and for H chondrite falls (Amean = 25.05) (Szurgot 2015e). Jezersko’s Fe/Si atomic ratio (0.742) leads to Amean = 24.66±0.24, which is close to the value determined by bulk composition. Jezersko’s Fe/Si atomic ratio is close to the value for H’s mean Fe/Si ratio: 0.762 for finds, and 0.807 for falls (Szurgot 2016a). This confirms that Jezersko belongs to H chondrites, as previously classified (Miler et al. 2014). Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also calculated. Jezersko’s Zmean = 12.16, and Amean/Zmean ratio is: 2.029 for composition without water. Jezersko’s silicates shown the values: Amean = 21.77, Zmean = 10.78, Amean/Z mean = 2.019, Fe/Si = 0.272, Amean(Fe/Si) = 21.84±0.06, and Jezersko’s Fe,Ni metal values: Amean = 56.12, Zmean = 26.19, and Amean/Z mean = 2.143. Two dependences: i) grain density dgr on Amean (Szurgot 2015a), and ii) grain density dgrain on Fe/Si atomic ratio (Szurgot 2017g), were used to predict grain density of Jezersko chondrite. It was established that dgr(Amean) leads to the values: 3.65±0.07 g/cm3 for Jezersko chondrite, 3.27±0.07 g/cm3 for silicates, and 7.83±0.07 g/cm3 for Fe,Ni metal of Jezersko meteorite. Dependence dgr(Fe/Si) predicts somewhat higher value grain density for Jezersko chondrite: 3.68±0.07 g/cm3, and 3.32±0.07 g/cm3 for silicates. All the predictions lead to the mean value of grain density for its weathering W2 degree: 3.67±0.03 g/cm3 for the whole rock of meteorite, and 3.29±0.03 g/cm3 for the silicates. It was established that due to terrestrial weathering, resulting in W2 weathering stage, Amean value of Jezersko chondrite is about 0.45 lower, Fe/Si atomic ratio is about 0.075 lower, and dgrain is about 0.06 g/cm3 lower than values for unweathered (W0) meteorite. Predicted porosity for Jezersko chondrite is: 10,1±0,7% for W2, and 11,5±0,5% for W0.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 140-159
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metoda 4M – nowe zastosowanie spektroskopii mössbauerowskiej w klasyfikacji zrównoważonych chondrytów zwyczajnych
4M method – the new application of Mössbauer spectroscopy for classification of equilibrated ordinary chondrites
Autorzy:
Woźniak, Marek
Karwowski, Łukasz
Gałązka-Friedman, Jolanta
Duda, Przemysław
Jakubowska, Martyna
Bogusz, Patrycja
Powiązania:
https://bibliotekanauki.pl/articles/1033156.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
4M method
Cluster Analysis
Mahalanobis distance
Multidimensional Discriminant Analysis
Mössbauer spectroscopy
Principal Components Analysis
meteorites
meteorites classification
ordinary chondrites
Opis:
The 4M method aims to determine the type of equilibrated ordinary chondrite only on the basis of the Mössbauer spectrum of the investigated meteorite. Mössbauer spectrum of non-weathered ordinary chondrite is comprised of four sub-spectra: two doublets and two sextets. One of the doublets consists of a signal from iron present in olivine and the other consists of a signal from iron present in pyroxene. Sextets on the other hand, contain signals from magnetically ordered iron. One sextet is related to the metallic phase (kamacite, taenite), whereas the second is related to troilite. A third of doublets, which emerges in weathered ordinary chondrites, is related to products of the oxidation of iron present in metallic phase. The spectral areas of olivine, pyroxenes, metallic phase and troilite, which were obtained from Mössbauer spectrum are proportional to the number of iron atoms present in relevant mineral phases. Some Mössbauer groups were inspired by this fact to construct different methods to determine the type (H, L, or LL) of investigated meteorites (Gałązka-Friedman et al. 2019, Hyp. Inter. 241(1)). However, these methods, based on subjective criteria, were only qualitative. Our group elaborated a quantitative method, which is based on objective criteria. We called it the "4M method" (where M are derived from meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis (MDA), Mahalanobis distance) (Woźniak et al. 2019). This method was using only the Mössbauer experimental data, to which it applied advanced statistical methods. The base, which was created from Mössbauer data, consisted of three clusters H, L, LL. These clusters were constructed with sets of 4-dimensional vectors. The vectors are comprised of spectral areas of Mössbauer spectrum: ol (value proportional to iron present in olivine), pyr (value proportional to iron present in pyroxene), met (value proportional to iron present in metallic phase), tr (value proportional to iron present in troilite). To determine the type of investigated ordinary chondrite, its ol, pyr, met and tr values with average values of variables obtained for clusters H, L and LL need to be compared. The comparison can be performed with the use of MDA and Mahalanobis distance. Once Mahalanobis distance of the investigated meteoriteis is known, the level of similarity to three types of ordinary chondrites can be calculated. Examples of such calculations were performed for seven ordinary chondrites: Goronyo, Carancas, New Concord, NWA 7733, Leoncin, Sołtmany and Pułtusk. They were made with the use of the new base composed of 62 non-weathered ordinary chondrites. All results obtained with the 4M method yielded results consistent with traditional mineralogical methods.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2020, 11; 125-140
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Średni ciężar atomowy chondrytu Vicência (LL3.2)
Mean atomic weight of Vicência LL3.2 chondrite
Autorzy:
Szurgot, Marian
Powiązania:
https://bibliotekanauki.pl/articles/1033113.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
LL3 chondrites
Mössbauer spectroscopy
Vicência chondrite
grain density
iron to silicon ratio
mean atomic number
mean atomic weight
ordinary chondrites
troilite content
Opis:
Mean atomic weight Amean of Vicência (LL3.2 S1W0, fall 2013) ordinary chondrite has been calculated using literature data (Keil et al. 2015) on chemical composition of the meteorite and using relationships: between mean atomic weight and Fe/Si atomic ratio, between Amean and grain density, and between Amean and magnetic susceptibility. It was shown that Vicência’s Amean = 22.91 for composition without water. This value is close to the mean atomic weight of LL chondrite falls, is close to Amean value of LL3 chondrite falls, and is close to Amean value of Semarkona LL3.0 chondrite. Vicência’s Fe/Si atomic ratio (0.492±0.050) leads to Amean = 23.06–23.26, which is close to the value determined by bulk composition. Vicência’s Fe/Si atomic ratio is close to the value for Semarkona’s (Fe/Si = 0.511), and is close to LL’s mean Fe/Si ratio (0.520). This confirms that Vicência belongs to LL chondrites, as previously classified. Using dependence between mean atomic weight and grain density leads to Amean = 21.89±0.54 (dgr = 3.28 g/cm3, Keil et al. 2015), and using dependence between Amean and magnetic susceptibility gives Amean = 23.01±0.24 (logc = 4.30, Keil et al. 2015). Arithmetic mean of Amean (dgr), Amean (logc), and Amean(Fe/Si), gives 22.72±0.73, the value close to Amean(bulk composition) determined using compositional data. Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also calculated. Vicência’s Zmean = 11.37, and Amean/Zmean ratio is: 2.015 for composition without water. Vicência’s silicates shown the values: Amean = 21,67, Zmean = 10.76, Amean/Z mean = 2.014, Fe/Si = 0.318, Amean(Fe/Si) = 22.07–22.18, and Fe, Ni metal values: Amean = 56.63, Zmean = 26.53, and Amean/Z mean = 2.135. Two dependences: i) grain density dgr on Amean, and ii) grain density dgr on Fe/Si atomic ratio, were used to determine/verify grain density of Vicência chondrite. It was established that dgr(Amean) leads to the values: 3,42 g/cm3 for Vicência chondrite, 3,25 g/cm3 for silicates, and 7,90 g/cm3 for Fe, Ni metal of Vicência meteorite. Dependence dgr(Fe/Si) predicts density for Vicência chondrite: 3,47–3,49 g/cm3, and for silicates: 3,32–3,35 g/cm3.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2018, 9; 126-144
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
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