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4 Acta Societatis Metheoriticae Polonorum

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Pierwsze znalezisko polskich mołdawitów

100%

Brachaniec T. , Karwowski Ł. , Szopa K.

tom 4

37-38

In Lower Silesia, in the late Miocene sediments moldavites were discovered. Finding of polish moldavites may change the existing model of tektites distribution, after the impact in the Ries crater area. Further studies are planned and should bring a new information.

Jak odróżnić oryginał od fałszywek: kopalny meteoryt z Lechówki

100%

Szopa K. , Karwowski Ł. , Krzykawski T. , Brachaniec T.

2018

tom 9

112-122

Value of meteorites can be explained at least in two aspects. From the scientific point of view they are priceless objects, which can bring important information about the very beginning of the Universe. Because of their rarity anduniqueness, the meteorites often are extremely expensive in the term of a commercial value. This situation is used by dishonest sellers who offer fake meteorites. It has happened with the paleometeorite remnants, which were originallyfound in Cretaceous-Paleogene clay boundary in Lechówka, Poland. The so-called fake Lechówka remnants were offered by one seller on domestic online shops. All grains had certificate of authenticity that was included with the sold grains. In this paper we described the most common and diagnostic features, which can be easily applied to distinguish the original meteorite remnants from the fake ones.

Czy w Polsce są autochtoniczne tektyty?

100%

Brachaniec T. , Szopa K. , Karwowski Ł.

tom 7

17-20

Undoubtedly, the river transport is very important in tektites distribution. Most of the moldavites are located in fluvial sediments, what indicates their redeposition origin. Similar situation is on the territory of Poland. Finding of the autochthonous Polish tektites seems very difficult and requires further fieldworks.

Metoda 4M – nowe zastosowanie spektroskopii mössbauerowskiej w klasyfikacji zrównoważonych chondrytów zwyczajnych

76%

Woźniak M. , Karwowski Ł. , Gałązka-Friedman J. , Duda P. , Jakubowska M. , Bogusz P.

tom 11

125-140

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.