Results 21 to 30 of about 30,877 (270)
Petrography of primary peridotites from the Ohsa-yama area, Okayama Prefecture [PDF]
, 1994 Ultramafic rocks exposed around Mt. Ohsa(= Ohsa-yama), Okayama prefecture, designated as "Ohsa-yama ultramafic body" all together, are one of the Alpine-type peridotites in the Sangun metamorphic belt.
Nozaka, Toshio, Shibata, Tsugio
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Geological setting and intrusion tectonics of the Kotalahti nickel-copper deposit, Finland [PDF]
Bulletin of the Geological Society of Finland, 1980 The wall rocks of the nickel bearing mafic and ultramafic plutonic rocks of Kotalahti are Archean banded granitoidic gneisses containing inliers of Archean metasediments and metavolcanics.
G. Gaál
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Prebiotic Organic Microstructures [PDF]
, 2011 Micro- and sub-micrometer spheres, tubules and fiber-filament soft structures have been synthesized in our experiments conducted with 3 MeV proton irradiations of a mixture of simple inorganic constituents, CO, N2 and H2O.
A Yoshihara +26 more
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Decreasing extents of Archean serpentinization contributed to the rise of an oxidized atmosphere
Nature Communications, 2021 Throughout the Archean, H2 generation via low-temperature ultramafic serpentinization likely helped prevent atmospheric O2 accumulation and continued until the abundance of ultramafic rocks diminished setting the stage for the Great Oxidation Event.
James Andrew M. Leong +2 more
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Carbonate alteration of ophiolitic rocks in the Arabian–Nubian Shield of Egypt: sources and compositions of the carbonating fluid and implications for the formation of Au deposits [PDF]
, 2016 Ultramafic portions of ophiolitic fragments in the Arabian–Nubian Shield (ANS) show pervasive carbonate alteration forming various degrees of carbonated serpentinites and listvenitic rocks.
Azer, Mokhles K. +9 more
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Geosciences, 2018 This case study investigates the influence of the mineralogical composition of ultramafic rocks derived from two ophiolite complexes from Greece (Veria-Naousa and Gerania) on their mechanical, physical and physicochemical properties.
Panagiota P. Giannakopoulou +6 more
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JGEET: Journal of Geoscience, Engineering, Environment and Technology, 2020 The research area is located in Asera District, North Konawe Regency, Southeast Sulawesi Province which has ultramafic rock lithology. The purpose of this study is to determine the characteristics of ultramafic igneous rocks using petrographic and ...
Hasria +4 more
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Journal of Spectral Imaging, 2022 The layered Sittampundi Anorthosite Complex is covered by mafic and ultramafic rocks including anorthosite, gabbro, pyroxenite and other igneous rocks. The ultramafic terrain has frequently undergone metamorphism.
K. Tamilarasan +5 more
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Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola Alkaline Province: a review [PDF]
, 2005 Igneous rocks of the Devonian Kola Alkaline Carbonatite Province (KACP) in NW Russia and eastern Finland can be classified into four groups: (a) primitive mantle-derived silica-undersaturated silicate magmas; (b) evolved alkaline and nepheline syenites; (
Balaganskaya, E. +4 more
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Olivine-chrome-spinel equilibrium in chromitites and ultramafites of Rai-Iz massif, Polar Urals
Литосфера, 2016 Olivine and chrome-spinel compositions from chromitites and ore-bearing metamorphosed ultramafic rocks of Rai-Iz massif were compared. It was established that olivine and spinel ferruginosity are directly proportional and increase monotonically from ...
P. B. Shirjaev, N. V. Vakhrusheva
doaj +2 more sources