On the issue of establishing the type of coal seams by «reduction» («oxidation») of fossil coals
Технічна інженерія, 2022 The yield of volatile substances during the thermal decomposition of coals and the oxygen content in the organic mass do not unambiguously characterize both the types of coals according to the expected reduction, and the manifestations of the hazardous ...
Ye.S. , M.I. , E.N. , M.V.
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U-Pb zircon geochronology of selected Archaean migmatites in eastern Finland [PDF]
Bulletin of the Geological Society of Finland, 2007 U-Pb SIMS data on eight samples (four mesosome-leucosome pairs) from migmatites in gneiss complexes are presented from the western part of the Archaean Karelian craton, eastern Finland. Most zircon grains in the mesosomes yield ages between 2.84 Ga and 2.
A. Käpyaho +2 more
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Infra-supra structure relations of a microcline-granite dome in the Somero area, Svecofennides, SW Finland [PDF]
Bulletin of the Geological Society of Finland, 1989 Internal structure and deformational history of two granite domains with markedly distinct tectono-metamorphic evolutions occur in the Somero area, SW Finland.
H. Stel +4 more
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Conodont color alteration; an index to organic metamorphism [PDF]
, 1975 A. G. Epstein, J. Epstein, L. D. Harris
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Frontiers in Earth Science, 2020 The role of near-surface snow processes for the formation of climate signals through densification into deep polar firn is still barely understood. To this end we have analyzed a shallow snow pit (0-3 meters) from EastGRIP (Greenland) and derived high ...
Maurine Montagnat +6 more
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The effect of aqueous alteration and metamorphism in the survival of presolar silicate grains in chondrites [PDF]
, 2008 Relatively small amounts (typically between 2-200 parts per million) of presolar grains have been preserved in the matrices of chondritic meteorites.
Bischoff +31 more
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Timing of late Palaeoproterozoic metamorphism in the northern Belomorian Belt, White Sea region: Conclusions from U-Pb isotopic data and P-T evidence [PDF]
Bulletin of the Geological Society of Finland, 2001 Brilliant-looking zircon crystals from a garnet-amphibolitic, metamorphosed mafic dyke at Lyagkomina in the Lake Kovdozero area, northern Belomorian Belt, most probably mark the 1875±4 Ma age of peak late Palaeoproterozoic regional metamorphism which ...
T. Skiöld +3 more
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Геодинамика и тектонофизика, 2021 Transformation of the oceanic crust into the continental one in orogenic belts is an important problem in petrological studies. In the paleocontinental sector of the Urals, a key object for tracing the stages of metamorphism and investigating the origin ...
G. Yu. Shardakova +4 more
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Late Precambrian U-Pb titanite age for peak regional metamorphism and deformation (Knoydartian orogeny) in the western Moine, Scotland [PDF]
, 2003 There has been controversy over the number and timing of orogenies in the Precambrian Moine block in the Scottish Caledonides since the earliest radiometric dating in the 1960s. This work challenges a recent hypothesis, that this sector of the Laurentian
Evans, J.A., Tanner, P.W.G.
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Relationship between deformation structure and partial melting in pelitic migmatites of Hamaden region, Sanandaj-Sirjan Zone [PDF]
پترولوژیThe present paper describes some field characteristics of deformation in a high-strain and high temperature zone in migmatitic rocks, with several kilometers wide occurring in Hamedan and Toyserkan regions, NW of the Sanandaj- Sirjan Zone.
Seyedeh Razieh Jafari, Leyli Izadi Kian
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