Results 41 to 50 of about 1,401 (174)
Мінеральні ресурси УкраїниSilicate analyzes of siltstones, argillites, sandstones, gravelites, and conglomerates were used to examine the lithochemical features of the clastic rocks of the Hrushka Formation.
T. M. Sokur +2 more
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Geological Journal, EarlyView.Petrography, thermobarometry, and pseudosection modelling reveal peak metamorphic conditions of 3–7.5 kbar and 520°C–800°C in Tonian‐Cryogenian orthogneisses of the Dom Feliciano Belt. Metamorphic field gradients of 27°C/km–39°C/km and variable exhumation mechanisms support correlation of these units as remnants of a Himalayan‐type Piratini Orogeny ...
Thaiane Niederauer‐Santos +6 more
wiley +1 more source
Food sources for the Ediacara biota communities
Nature Communications, 2020 Complex macroscopic organisms are first found in the Ediacaran period, but their ecology during this time is not well understood. Here, Bobrovskiy et al.
Ilya Bobrovskiy +3 more
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Diversity of the Vendian fossils of Podillia (Western Ukraine)
Geo&Bio, 2020 Diversity ofVendian fossil associations is a common feature. The diversity depends on many factors: firstly, physical conditions in the basin, in which animals lived (i.e.
Volodymyr Grytsenko
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Appraisal of Six Natural Mica Reference Materials for In Situ Rb‐Sr Geochronology
Geostandards and Geoanalytical Research, EarlyView.Key Points Evaluated six natural mica reference materials for in situ LA‐ICP‐MS/MS Rb‐Sr geochronology using geochemical, microstructural and isotopic characterisation. Identified robust primary reference materials: Mount Dromedary biotite (99.37 Ma) and Mica‐Fe biotite (307.75 Ma). La Posta biotite and Högsbo muscovite are suitable secondary reference
Hugo K.H. Olierook +38 more
wiley +1 more source
Anais da Academia Brasileira de Ciências, 2014 This study reports the first known occurrence of the Ediacaran fauna in northeastern Brazil (at Pacujá Municipality, northwestern state of Ceará) and presents preliminary interpretations of its significance.
FRANCISCO R.G. BARROSO +3 more
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The Unexpected Discovery of Paleocene? Coals in Outcrops Thought to Be Cambrian, Al Huqf, Oman
Journal of Petroleum Geology, EarlyView.ABSTRACT Two brown organic deposits were encountered whilst investigating kaolinitic claystones thought to occur at the base of a Cambrian formation at outcrop. The age of these organic deposits is probably Paleocene from palynology. Organic petrography shows that they are subbituminous coals with some oil source potential.
Mohammed H. Al Kindi +4 more
wiley +1 more source
Ediacaran metazoan fossil record from South America and its implications in the studies about origin and complexification of animal life [PDF]
Geologia USP. Série Científica, 2013 The Ediacaran Period marks the first appearance of complex macroscopic organisms in the fossil record. Current evidence indicates that Ediacara biota is composed of animals, groups of extinct giant protists, algae and other organisms without proven ...
Bruno Becker Kerber +4 more
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Arumberiamorph structure in modern microbial mats: implications for Ediacaran palaeobiology [PDF]
BSGF - Earth Sciences Bulletin, 2017 In the course of studying modern halotolerant microbial mats in salterns near the village of Kervalet, western France, we observed fanning-out and curved series of macroscopic ridges on the surface of a newly formed biofilm.
Kolesnikov Anton V. +4 more
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On the coevolution of Ediacaran oceans and animals [PDF]
Proceedings of the National Academy of Sciences, 2008 Fe speciation and S-isotope of pyrite data from the terminal Proterozoic Sheepbed Formation in Canada and Doushantuo Formation in China reveal that ocean deep waters were anoxic after the global glaciations (snowball Earth) ending 635 million years ago, but that marine sulfate concentrations and inferentially atmospheric oxygen levels were higher than ...
Yanan, Shen +2 more
openaire +2 more sources