The research was focused on strewnfield in “Meteorite Morasko” reserve. The main goal of the project was to find correlation between chemical composition of soil and concentration of cosmogenic material which was discovered in the region. After field prospection the sampling was made for three reference regions in the reserve. ICP-MS method was used to determine the elemental composition of soil samples. Investigation has been carried out to indicate the chemical components which iron meteorite matrix is built of like Fe, Ni and Co. Results of the study gave information about distribution and correlation of chemical components in the reserve.
This article describes the results of metallurgical studies of three experiments on hammering products made of iron meteorites. The objective qualification criteria of these materials created by plastic deformation were defined: carburization in smithing hearth, creating martensitic structure and the existence of small-martensitic weld and increased content of nickel.
Iron meteorites are the only ones to be linked with terrestrial impact craters. As studies show, over half of all iron meteorites shows signs of being shocked some time in their history to pressures over 130 kb. This paper is a short review of main shock metamorphism features in iron meteorites. Mechanisms leading to forming shock metamorphism features are described and examples of application of shock metamorphism studies are given.
This article complements the previous publication included in the materials for the 2nd Meteorite Seminar in Olsztyn in 2003 and also in 2004 in Meteoritics & Planetary Science with artifacts about which I did not write then and new discoveries. In recent time, archaeologists have discovered more confirmed artifacts that were made of meteorites. Scientists were puzzled that iron objects were found among the artifacts of the Bronze Age. Initially, it was assumed that these were the beginnings of metallurgy, but after careful research, it turned out that they are cold-forged items and the metal is of cosmic origin. How many more interesting and unusual old artifacts made by human hands from materials obtained from outer space will be discovered. Can there be more such artifacts in museums in Poland? It seems to me that a comprehensive inventory and research action should be carried out to verify this. Finally, as a lawyer, I can add that artifacts made of meteorites are the only meteorites in the world protected by law in one hundred percent, because they are monuments of world material culture.
Radioactive cobalt isotope 60Co is produced in neutron activation process of stable isotope 59Co by neutron capture reaction 59Co(n,g)60Co, in solar wind charge exchange 60Ni(n,p)60Co or in spallation process 62Ni(n,p2n)60Co. These processes are responsible for isotope 60Co production either in nuclear reactor on Earth or beyond – in stars and in meteorites (induced by cosmic rays). In this work the results of 60Co measurements in metal sources by gamma spectrometry laboratory are presented. A metal reference radioactive standards made up of steel cast with discs shaped geometries and different diameters have been tested in gamma-ray spectrometry measurement system. The reference activity concentrations of 60Co were in the range of (0.291±0.010) Bq·g–1 to (1.544±0.030) Bq·g–1. The mean minimal detectable activities (MDA) obtained by series of the 6 to 18 hours lasting measurements of described above standards with HPGe detectors carried out in NCBJ OR POLATOM were in the range of 6.1 mBq·g–1 to 8.5 mBq·g–1. The results correspond to the values of 60Co activity concentration measured in the iron meteorites with young terrestrial ages.
Iron meteorites are meteorites whose main constituent is iron (Fe) and nickel (Ni), which occur in two forms of Fe-Ni minerals – kamacite and taenite. Since their composition makes them more resistant to shattering (crushing), and they are more challenging to ablate when passing through the atmosphere, they statistically fall in the form of larger lumps than stone or iron-stone meteorites. Their metallic structure and highly high weight make them easy to distinguish from ordinary rocks. The mass of all known iron meteorites is over 500 tons, which is ~89% of known meteorites, but falls of iron meteorites account for only 4.56% of all observed falls (wiki.meteoritica.pl). The ten largest meteorites in the world are iron meteorites! In the past, the term siderite was used to describe iron meteorites. The classification of iron meteorites is based on two criteria. The older method is based on the average nickel content and the crystal structure revealed on cut and etched surfaces, the so-called the Thomson-Widmanstätten patterns. In this division, we distinguish three groups: hexahedrites (4–6 wt.% Ni), the most popular octahedrites (6–12 wt.% Ni) and ataxites (>12 wt.% Ni). The second, more recent method of classifying iron meteorites is based on their chemical composition, in particular the content of trace elements such as germanium (Ge), gallium (Ga), platinum (Pt), arsenic (As), gold ( Au) and iridium (Ir). Another parameter that defines the groups of iron meteorites is their mineral composition. “Indicator” minerals are in the form of various compounds and multiple shapes and sizes: sulfides, phosphides, carbides, nitrides, and silicate inclusions. Trace element content versus nickel content reveals chemical clusters representing the different chemical groups of iron meteorites. Some of the iron meteorites come from the partially differentiated asteroid ruptured at the beginning of forming the iron core and the silicate-rich shell (these are groups IAB and IIE). The remaining meteorites from other groups come from the nuclei of minor differentiated asteroids, shattered in collisions shortly after formation.
PL
Meteoryty żelazne to grupa meteorytów, których głównym składnikiem jest żelazo (Fe) i nikiel (Ni), występujące w dwóch formach stopu Fe-Ni – kamacytu i taenitu. Ponieważ ich skład czyni je bardziej odpornymi na rozbicie (kruszenie) i trudniej ulegają procesowi ablacji przy przelocie przez atmosferę, więc statystycznie spadają one w postaci większych brył niż meteoryty kamienne lub żelazno-kamienne. Ich metaliczna budowa i wyjątkowo duża waga czynią z nich meteoryty łatwe do odróżnienia od zwykłych skał. Masa wszystkich znanych meteorytów żelaznych wynosi ponad 500 ton, co stanowi ~89% masy znanych meteorytów, ale spadki meteorytów żelaznych stanowią już tylko 4,56% wszystkich obserwowanych spadków (Wiki.Meteoritica.pl). Dziesięć największych okazów meteorytów na świecie to meteoryty żelazne! Dawniej na określenie meteorytów żelaznych używano określenia syderyt (siderite). Podziału meteorytów żelaznych dokonuje się według dwóch kryteriów. Starsza metoda bazuje na średniej zawartości niklu i na strukturze krystalicznej ujawniającej się na przeciętych i wytrawionych powierzchniach tzw. figury Thomsona-Widmanstättena. Przy takim podziale wyróżniamy trzy grupy: heksaedryty (hexahedrites) (śr. 4–6wt.% Ni), najpopularniejsze oktaedryty (octahedrites) (śr. 6–12wt.% Ni) oraz ataksyty (ataxites) (>12wt.% Ni). Druga, nowsza metoda klasyfikacji meteorytów żelaznych, opiera się na ich składzie chemicznym, w szczególności na zawartości pierwiastków śladowych (trace elements), takich jak german (Ge), gal (Ga), platyna (Pt), arsen (As), złoto (Au) i iryd (Ir). Drugim parametrem definiującym grupy meteorytów żelaznych jest ich skład mineralny. Minerałami „wskaźnikowymi” są występujące w formie różnych związków oraz w różnej formie i wielkości: siarczki, fosforki, węgliki, azotki i inkluzje krzemianowe. Zawartość pierwiastków śladowych versus zawartość niklu ujawnia chemiczne klastry (skupienia, clusters) reprezentujące różne chemiczne grupy meteorytów żelaznych. Część meteorytów żelaznych pochodzi z częściowo zdyferencjonowanych planetozymali rozerwanych na początku formowania żelaznego jądra i bogatej w krzemiany skorupy (to grupy IAB i IIE). Pozostałe meteoryty z innych grup pochodzą z jąder małych całkowicie zdyferencjonowanych planetozymali, rozbitych w zderzeniach, krótko po uformowaniu się.
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