Results 51 to 60 of about 52,439 (271)
New carbonaceous chondrite Northwest Africa 11781 (CM2)
Литосфера, 2019 Research subject. The article presents the results of a study of a new meteorite Northwest Africa 11781.Material and methods. The material for the study was a fragment of a meteorite weighing 15.56 g, from which 4 transparent polished sections with a ...
K. A. Dugushkina, S. V. Berzin
doaj +1 more source
Angewandte Chemie International Edition, EarlyView.Rare earth elements can act as mediators in a prebiotic reaction network, producing various intermediates of the citric acid cycle starting from glyoxylate and pyruvate. The ionic radius and the resulting variation in Lewis acidity has a significant influence on the observed product scope.
Jonathan Gutenthaler‐Tietze +2 more
wiley +1 more source
Geological Journal, EarlyView.Charnockites with 2691–2607 Ma magmatic ages from the NMZ show arc‐magmatic geochemical signatures. They correspond to the lower‐crustal equivalent of the Chilimanzi Suite Granite in the Zimbabwe Craton. Lu‐Hf isotopic data of magmatic zircons show negative εHf(t) values (−11.18 to −2.20) with TDMC ages of 3699–3158 Ma, suggesting their protolith ...
Toshiaki Tsunogae +6 more
wiley +1 more source
Iridium anomaly in the cretaceous-paleogene boundary at Højerup (Stevns Klint, Denmark) and Woodside Creek (New Zealand): The question of an enormous proportion of extraterrestrial component [PDF]
Journal of the Serbian Chemical Society, 2012 The Cretaceous-Paleogene boundary clays at Højerup and Woodside Creek show anomalous enrichments of iridium compared with the marine sedimentary rocks.
Premović Pavle I. +2 more
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Geological Journal, EarlyView.The Pangkaimen Au–Ag deposits belong to the epithermal Au deposits, which are of great significance for guiding the research and development of this type of gold deposit. Metallogenic model diagram of Pangkaimen Au–Ag deposit. ABSTRACT The gold (Au) metallogenic belt in the northern Great Xing'an Range is characterised by the wide occurrence of the ...
Sheng Lu +8 more
wiley +1 more source
D/H ratios of the inner Solar System [PDF]
, 2017 The original hydrogen isotope (D/H) ratios of different planetary bodies may indicate where each body formed in the Solar System. However, geological and atmospheric processes can alter these ratios through time.
Hallis, Lydia
core +1 more source
Proceedings of the National Academy of Sciences of the United States of America, 2018 Significance Refractory organic matter found in volatile-rich asteroidal materials essentially comprise the elements C, H, O, N, and S, which are thought to be important building blocks for life.
R. Tartèse +4 more
semanticscholar +1 more source
Thermal evolution and sintering of chondritic planetesimals III. Modelling the heat conductivity of porous chondrite material [PDF]
, 2016 The construction of models for the internal constitution and the temporal evolution of large planetesimals, the parent bodies of chondrites, requires information on the heat conductivity of the complex mixture of minerals and iron metal found in ...
S. Henke, H. Gail, M. Trieloff
semanticscholar +1 more source
Journal of Metamorphic Geology, EarlyView.ABSTRACT Elevated heat flow associated with mafic magmatism in accretionary orogens has often been proposed as a driving mechanism for (ultra)high‐temperature (UHT) metamorphism and anatexis. The Sancheong–Hadong complex, located in the southern Yeongnam Massif, Korea, consists of a ca.
Yuyoung Lee +3 more
wiley +1 more source
Study of the Extraterrestrial Materials at Antarctica, IV. : On the Yamato Meteorites
Antarctic Record, 1974 Additional mineralogical and chemical studies of the Yamato meteorites are under way. The mode analysis and the optical properties in thin sections are examined under a microscope.
Makoto SHIMA +2 more
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