Results 71 to 80 of about 32,483 (245)
Diminished greenhouse warming from Archean methane due to solar absorption lines [PDF]
Climate of the Past, 2015 Previous research has shown that methane may have been sustained at high concentrations in the Archean atmosphere, helping to offset lower insolation and solve the faint young sun problem.
B. Byrne, C. Goldblatt
doaj +1 more source
Plant, Cell &Environment, EarlyView.ABSTRACT The multi‐elemental profile has repeatedly been proposed as a reliable indicator of the geographical origin of plant‐derived foods, as mineral composition accurately reflects the local soil geochemistry and environmental factors. However, this approach may fail in distinguishing specimens from nearby locations, which are expected to be exposed
Ana Sayago +2 more
wiley +1 more source
How widely is the Andean type of continental margin represented in the Archean [PDF]
Application of the principle of uniformitarianism to the Archean was discussed in a search for evidence of Archean-type continental margins in Archean rocks.
Burke, Kevin
core +1 more source
Microbial mats in dinosaur ichnocoenoses
Sedimentology, EarlyView.ABSTRACT Until now, the significance of microbial mats in preservation of dinosaur tracks and in reconstructing the palaeoenvironment in which dinosaurs roamed was rarely studied. Dinosaur tracks are commonly found close to ancient aquatic bodies where moist sediment had once allowed footstep registration.
Nora Noffke +3 more
wiley +1 more source
Journal of the Geological Survey of BrazilGamma-ray spectrometric responses of Archean rocks were studied in order to define a characteristic signature for these rocks. As the half-life of the most frequent Thorium isotope (232Th – half life of 14.05 Ga) is more than 3 times longer relative to ...
Marcus Flavio Nogueira Chiarini +9 more
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Archean phosphorus liberation induced by iron redox geochemistry
Nature Communications, 2018 Phosphorus is presumed to have been a limiting nutrient in the Archean ocean due to binding to iron oxides. Here, the authors show the heating of iron with phosphate results in the reduction of phosphate to the ion phosphite, which is solubilized and ...
Barry Herschy +8 more
doaj +1 more source
Workshop on Early Crustal Genesis: Implications from Earth [PDF]
Ways to foster increased study of the early evolution of the Earth, considering the planet as a whole, were explored and recommendations were made to NASA with the intent of exploring optimal ways for integrating Archean studies with problems of ...
Phinney, W. C.
core +1 more source
Prebiotic Organic Globules [PDF]
, 2010 Analogs of organic globules observed in carbonaceous chondrite meteorites and in interplanetary dust particles and of rod to spherical structures observed in terrestrial archean microstructures have been synthesized in our experiments conducted with ...
Marie-Paule Bassez, Yoshinori Takano
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Sedimentology, EarlyView.ABSTRACT One of the largest wetlands on Earth, the Brazilian Pantanal contains roughly 10 000 natural lakes, about 1000 of which are hypersaline. In these environmentally stressful settings, animal life struggles to survive, while cyanobacteria form extensive mats.
Lucas V. Warren +5 more
wiley +1 more source
Geosciences, 2018 The Hf-Nd isotope systems are coupled in magmatic systems, but incongruent Hf weathering (‘zircon effect’) of the continental crust leads to a decoupling of the Hf-Nd isotope systems in low-temperature environments during weathering and erosion processes.
Sebastian Viehmann
doaj +1 more source