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1
Content available remote Time of fall and some properties of the Morasko meteorite
100%
EN
The time of fall of a meteorite and the appearance of the impact craters in Morasko have been documented by the thermoluminescene method, 14C dating, as well as palynological estimation. The extraterrestrial effect on the lithology and morphology of Moraska Góra (Morasko Hill) took place about 5000 years BP. Morasko meteorite is composed in about 98 wt. % of Fe--Ni alloy and in about 2 wt. % of dark FeS nodules, up to 20 mm in diameter. The principal Fe--Ni alloy is kamacite with nearly 6% Ni and taenite with up to 30% of Ni. FeS occurs as troilite, being often wrapped up by rounded flakes of graphite.
EN
Cosmogenic radionuclides in meteoroids are produced in space in the process of activation. These nuclides have various lifetimes in range from a few days to several hundred thousand years and can therefore be helpful in solving several problems related to the study of meteoroids and their remains, both in space and on the Earth. The simplest application of cosmogenic radionuclide decay in meteorites is to determine the terrestrial age of meteorites, especially those whose fall has not been observed. In this article, we present an additional application of cosmogenic radionuclide measurements, namely for the verification of origin of rocks that show equivocal features and may potentially represent meteorites.
3
Content available Kratery meteorytowe na Marsie
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2011
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tom 2
40-56
EN
Meteorite craters, volcanoes and deep valleys are main obiects of Mars topography. The are many tausend or millions of craters and they are very different, with diameters of only centimeters to big basins with diameters of 25oo kilometers. The age of oldest craters on Mars is about 3,9 billions year.
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tom 15
96-115
EN
Confocal microscopy is commonly used in mineralogy for structural analysis and to investigate the chemical composition of minerals. In our work we performed imaging of structural defects in meteorites i.e. imaging of microstructures, inclusions, fractures and cracks. Information obtained in this way enables better understanding of minerals' origin and evolution. The aim of our work was not concentrated on the deep description of physical processes related to confocal microscope (CSLM) imaging. This paper is limited to the presentation of a few CSLM functions and possibilities, which have practical application in the interpretation of fluorescence microscope imaging of minerals. Confocal microscopy enables identification and preview of localization of selected minerals and therefore can be used to image of the distribution of chemical compounds in minerals.
EN
The elemental composition, mineral composition and microstructure of the HaH 286 eucrite found in Lybia in 2000 were studied by analytical electron microscopy. It was established that the mean elemental composition of HaH 286 and atomic and molar ratios: Fe/Mn = 34, Mg/Mg+Fe = 36, Na/Al = 0.066, and Ca/Al = 0.73 are typical of eucrites, and two main meteorite minerals have the mean composition: clinopyroxene En34Fs59Wo7 and plagioclase feldspar An88Ab12. Variations in the composition of pyroxenes and plagioclases are as follows: pyroxene En34-36Fs53-62Wo3-13 and plagioclase: An86-100Ab14-0. Pyroxene is represented by pigeonite and by orthopyroxene. Chromite, ilmenite and silica are minor minerals. The composition, atomic ratios and microstructure indicate that the HaH 286 meteorite is a pyroxene-plagioclase basaltic achondrite, a non-cumulate eucrite with the composition of plagioclase changing between anorthite and bytownite.
6
Content available Badania mikroskopowe ureilitu NWA XXX
70%
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2011
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tom 2
138-146
EN
New NWA XXX ureilite found in 2006 was investigated by optical microscopy in reflection and in transmission. Olivines, pigeonite, metal veins and dots, and carbon phases have been revealed and their features and distribution studied. Twinning of pigeonite, reduction rims, and poikilitic inclusions of olivine in large pigeonite crystals have been identified and characterized. NWA XXX meteorite belongs to olivine-pigeonite ureilites.
EN
Shock impact-produced mineral alterations in two thin sections of the recently found Csátalja H4 ordinary chondrite meteorite are compared. Peak positions of Raman and infrared spectra of mineral clasts show peaks shifted in wavenumber relative to unshocked reference minerals, and both peak shifts and FWHM values seem to correlate to each other. In the less shocked thin section (Csátalja-1) a more monomineralic and homogeneous composition indicate shock pressures of <15 GPa, while the more shocked Csátalja-2 indicates shock pressure in the 15–17 GPa range. The highest identified infrared peak position shifts range between –48 and +28 cm–1 with peak broadening between 60–84 cm–1 in the case of the feldspars, which, together with sulphide globules, were produced by the shock itself. Feldspar spectra could be detected only by FTIR spectroscopy, but in most cases (above the S3 shock level) the mixed type of the pyroxene-feldspar spectra (both peaks in the same spectra) is in agreement with the shock-produced secondary feldspars. These grains are located around crystalline borders, and probably formed by selective melting, due to shock annealing. In reconstruction of the shock history, an early fragmentation by a lower shock effect and a later increased shock level-related vein and melt pocket formation occurred, with subsequent shock annealing; temporal reconstruction of the shock event is possible only in part. The joint usage of Raman and infrared spectroscopy provided useful insights into the shock-produced changes and their spatial inhomogeneity, while shocked feldspar could be better detected by infrared than by the Raman method.
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tom 8
23-29
EN
The paper presents results of bathymetric measurements performed on three crater lakes located in the “Meteoryt Morasko” reserve in west Poland. The maximum depth of the largest of the analysed lakes (1695 m2) was determined to amount to 2.6 m. The parameters of the lake (surface area, depth, etc.) are largely determined by a ditch dug through the crater in the north-western part of the lake, affecting the maximum water volume accumulated in the lake.
9
Content available Meteors and meteorite falls in Morocco
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EN
During the last eighty years, thirteen meteorite falls were recorded in Morocco, which ten are well documented and named Douar Mghila, Oued el Hadjar, Itqiy, Zag, Bensour, Oum Dreyga, Benguerir, Tamdakht, Tissint and Aoussred. It represent only 0.011 % of the Moroccan declared meteorites.The authenticated observed falls represent three types of different meteorites, eight ordinary chondrites (Four of type LL, three of type H and one of type EH), one carbonaceous chondrite and one Shergottite basaltic achondrites. The Morocco meteorite fall recovery rate, during the past eighty years, is low 0.11 falls per year on average per 2.11 km2 (or approximately one fall recovery per 10 year time interval).
EN
New NWA XXX ureilite was investigated by analytical electron microscopy to determine elemental and mineral composition of the meteorite. The main minerals: olivines and clinopyroxenes have been identified and characterized. The texture, elemental and mineral composition of the meteorite are typical of olivine-pyroxene achondrites.
11
60%
EN
Cosmogenic radionuclides were measured in two specimens of the Sołtmany chondrite (L6) that fell on April 30, 2011. The first fragment (154.9 g) was measured 12 days after the fall and the second piece (120 g), 53 days after the fall. Both fragments were measured by means of non-destructive gamma ray spectroscopy. The first specimen was examined with an ultra-low background high purity germanium (HPGe) detector in a deep underground laboratory. A standard low-background HPGe detector was used to examine the second fragment in a ground level laboratory. Twelve cosmogenic nuclides were detected in the activity range of 0.030 m・Bq g–1 until 1.5 m・Bq g–1 Their activities place constraints on the exposure history of the meteorite and reflect the effect of solar modulation of galactic cosmic rays during the solar maximum. On the activities of expected radionuclides 60 Co (< 0.0075 m・Bq g–1) and 44 Ti (< 0.023 m・Bq g–1) only upper limits could be given. Sołtmany is part of a group of only 14 meteorites where 52 Mn (5.591 d half life) could be determined.
12
60%
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tom 14
141-156
EN
In 2022, there were ten meteorites found worldwide after fresh falls. These are primarily ordinary chondrites, but one achondrite fall was also recorded. Meteorite falls occurred in the United States (3) and China (2) but also in Algeria, Brazil, Slovakia, India, and the Philippines. This paper shows how these meteorites were found and provides conclusions before future searches.
13
60%
EN
Based on petrological, mineralogical and geochemical analyses, the authors classified the new meteorite Northwest Africa 11778 as an ordinary chondrite H5, S2, W1. It is a single stone with mass 767.5 g and with well-preserved black fusion crust with brown shade (Fig. 1). This meteorite was found in Sahara Desert and it was purchased by Wroclaw University of Science and Technology, Faculty of Geoengineering, Mining and Geology from Moroccan dealer in Zagora in June 2013. The most characteristic component of analyzed chondrite are different types of chondrules (barred olivine – BO, porphyritic olivine – PO, granular olivine – GO, radial pyroxene – RP, porphyritic olivine-pyroxene – POP, cryptocrystalline – C) (Fig. 2), which constitute 75% of meteorite. Their size is in range 0.2–1.2 mm, with average chondrule size ca. 0.6 mm. Bigger porphyritic olivine chondrules with diameter up to 1.5 mm rarely occur. The chemical composition of olivine crystals (Fa 18 mol%) and pyroxene crystals (Fs 16.2 mol%) proves this meteorite to be an H chondrite (Tab. 1, Fig. 4–5, App. 1–2). The averaged concentration of major elements in the classified meteorite is comparable to their mean content in H chondrites (Fig. 8). The meteorite NWA 11778 contains only slightly less Mg and Al than average H chondrites (Tab. 2). Among the other analysed elements, values distinctly out of the range of typical concentrations for H chondrites are characteristic of Hg and Eu (lower concentration in the NWA 11778 meteorite) (Tab. 3, Fig. 8–9). The presence of chondrules with predominantly sharp boundaries (Fig. 2), secondary feldspar crystals with sizes of up to 50 mm, chiefly crystalline mesostasis and only secondarily – devitrified glass in chondrules, and transparent crystalline matrix (with olivine crystals up to 0.26 mm and pyroxenes up to 0.30 mm in size), as well as common occurrence of untwinned rhombic pyroxenes prove the classified meteorite to belong to petrological type 5. It is additionally confirmed by mean Ni content in troilite below 0.5 wt% (0.04 wt%) (Tab. 1, App. 4) and carbon content below 0.2 wt% (0.07 wt%) (Tab. 2). Undulatory extinction in some olivine and pyroxene crystals and the presence of irregular fractures in the NWA 11778 chondrite enables specifying its shock level as S2. The weathering grade adopted for the NWA 11778 chondrite was W1, as visible weathering changes cover only the marginal parts of FeNi alloy grains. As a result of the weathering of 10–20% of FeNi grains, iron oxides and hydroxides are formed. These secondary weathering Fe3+ compounds also fill cracks, forming veins running between chondrules within matrix (Fig. 3).
14
Content available Bulk chemical composition of Sołtmany chondrite
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EN
The authors examined the bulk chemical composition of the Sołtmany chondrite which fell on April 30th, 2011 in Northern Poland. Based on the analysis of 47 elements, it was concluded that Sołtmany is representative of L-type of ordinary chondrites. However, compared to the average values observed in other L-type ordinary chondrites, Sołtmany displays higher content of Ni, P, Cd, Pb, and As. The Ni and P content closely resembles typical values for H-type ordinary chondrites. Furthermore, Sołtmany displays other distinct properties including very low Zn content and lower contents of Mo and Zr than the average values found in other L-type ordinary chondrites. Consistent with other L-type ordinary chondrites, the absolute content of REE in Sołtmany is higher than that of CI-type carbonaceous chondrites while the REE trend lines for both Sołtmany and CI-chondrites are similar. Due to similar times of year of when both falls took place and the proximity of their strewn fields, the chemical composition of Sołtmany was compared with that of Jesenice, an L6 ordinary chondrite which fell on April 9th, 2009 in Europe. The analysis led to a conclusion that Sołtmany and Jesenice are not launch-paired. Nevertheless, even though they do not represent fragments of the same meteoroid, their origin on a common parent body (an asteroid – planetesimal) cannot be conclusively ruled out on the sole basis of their bulk chemical composition.
15
Content available Potential extraterrestrial sources of lithium
60%
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tom Vol. 65, No. 4
195--203
EN
Extracting raw materials from extraterrestrial sources is a prerequisite for the expansion of our civilization into space. It will be necessary to acquire there practically all commonly used elements – including lithium. The most valuable source of this element currently appears to be lunar soil and rocks, especially K-rich rocks and breccias (>10 ppm of Li). Among the meteorites, the highest content of lithium is characterized by lunar mare basalts and gabbro, eucrites, Martian polymict breccia, nakhlites, howardites (>5 ppm), shergottites, chassignites, lunar anorthosites breccias, mesosiderites, ureilites (>2.5 ppm), diogenites, LL, angrites, H (>2 ppm), L, CM, CO, CV, EH, CI (>1.5 ppm), brachinites, aubrites, EL, CR (>1 ppm), CK and main-group pallasites (<1 ppm). This means that a potential extraterrestrial source of lithium can be the Moon, Mars, and the 4 Vesta minor planet considered as the probable parent body of HED meteorites.
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2022
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tom 13
67-106
EN
The paper presents the circumstances and data accompanying meteorite falls in recent years. The study contains descriptions of 21 falls observed in 2020 and 15 falls in 2021. These phenomena took place on all continents, except the polar regions. In conclusion, this work is a collection of several dozen stories about freshly fallen meteorites. They show many aspects connected with the observations and the hunting for new specimens.
EN
One of the largest observed stone meteorite shower in the history of mankind on Earth took place on Thursday evening on January 30, 1868, about seven o’clock near Pułtusk in Poland. Despite the 150th anniversary of the fall of chondrite officially classified as Pułtusk H5 with a shock stage S3 there is still little published data on the chemical composition of minerals of this chondrite as well as its petrological characteristics in the literature. The authors carried out mineralogical and petrological research that will help a little to fill this gap in knowledge about the Pułtusk chondrite. Meteorite specimens found by Piotr Kuś in 2015 and investigated by the authors are undoubtedly part of the Pułtusk fall of January 30, 1868. They can be classified as ordinary chondrite H5, S2,W2. The authors stated that the studied rock is characterized by a varied shock level -from S1 to S2/3, as well as it contains chondrules of the chromite-plagioclase unequilibrated rock. In the composition of the examined fragment of Pułtusk chondrite, the authors identified silicates: olivine, diopside, bronzite and clinohyperstene, and oligoclase, oxides: chromite (and spinel), sulfides: troilite, FeNi alloy mineral phases: kamacite and taenite, as well as phosphates: merrilite and apatite. The chemical composition of olivine crystals as well as low- and high-Ca pyroxenes crystals and plagioclase crystals (about the composition of oligoclase) confirms that the examined specimen comes from the Pułtusk fall and it is a rock that should be classified as a petrographic type H5.
PL
Krater meteorytu Gardnos znajduje się w Norwegii, ok. 125 km na północny zachód od Oslo. Cała struktura jest dobrze widoczna w terenie dzięki licznym odkrywkom brekcji impaktowych i utworów poimpaktowych występujących w okręgu o promieniu ok. 5 km. Główne typy skał impaktowych w rejonie krateru Gardnos to autochtoniczna brekcja z Gardnos oraz przykrywająca ją allochto­niczna brekcja impaktowa (suevit). W artykule omówiono petrografię tych skał. Brekcja z Gardnos jest brekcją lityczną, złożoną ze spękanych fragmentów skał, ale nie zawiera fragmentów stopu. Suevit jest brekcją polimiktyczną, zawierającą małe fragmenty zrekrystalizowanego stopu z klastami skał i minerałów.
EN
The crater of the Gardnos meteorite is located in Norway, about 125 km north-west of Oslo. The structure is well seen due to the outcrops of impact breccias and post-impact deposits that form a circle with a radius of about 5 km. Main types of the impact rocks in the Gardnos area are the autochthonous Gardnos breccia and its cover – allochthonous suevite breccia. The petrological characteristics of these rocks are presented. The Gardnos breccia is a lithic breccia, composed of fissured rock fragments, without melt components. The suevite is a polymictic breccia, built of small fragments composed of recrystallized melt and clasts of rocks and minerals.
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