Search Results - "Geochemical cycle"

Geochemical behaviour and risk assessment of trace elements in a tropical river, Northwest Borneo by Prabakaran, K., Eswaramoorthi, S., Ramasamy, Nagarajan, Anandkumar, A., Francis, Merlin

“…Moreover, the trace elements in the continental dust (aerosols) constitute a significant component in their geochemical cycling. Due to their high mobility, the trace elements in the micron and sub-micron scale have biogeochemical significance in the coastal zone. …”
Get full text

Primitive oxygen-isotope ratio recorded in magmatic zircon from the Mid-Atlantic Ridge by Cavosie, Aaron, Kita, N., Valley, J.

“…The oxygen-isotope composition of the Earth's upper mantle is an important reference for understanding mantle and crust geochemical cycles. Olivine is the most commonly used mineral for determining the influence of crustal processes on the oxygen-isotope ratio (d18O) of primitive rocks, however it is an uncommon mineral in continental crust and readily alters at or near Earth's surface. …”
Get full text

Astronomical constraints on the duration of the Early Jurassic Pliensbachian Stage and global climatic fluctuations by Ruhl, Micha, Hesselbo, Stephen P., Hinnov, Linda, Jenkyns, Hugh C., Xu, Weimu, Riding, James B., Storm, Marisa S., Minisini, Daniel, Ullmann, Clemens V., Leng, Melanie J.

“…The Early Jurassic was marked by multiple periods of major global climatic and palaeoceanographic change, biotic turnover and perturbed global geochemical cycles, commonly linked to large igneous province volcanism. …”
Get full text

The effect of subduction on the sulphur, carbon and redox budget of lithospheric mantle by Evans, Katy, Powell, R.

“…The fate of these components is poorly known, but is intimately linked to the global geochemical cycles of iron, carbon and sulphur, the genesis of arc-related ore deposits, the temporal evolution of mantle redox state and subduction-related earthquakes and magmatism. thermocalc is used to provide first-order constraints on the effect of subduction zone metamorphism on metamorphic redistribution of iron, carbon, sulphur and water in ultramafic rocks via construction of P−T and T-X(O) pseudosections with open system calculation of the effect of fluid loss. …”
Get full text

Precipitation of iron silicate nanoparticles in early Precambrian oceans marks Earth’s first iron age by Rasmussen, Birger, Krapež, Bryan, Muhling, Janet, Suvorova, A.

“…Our results imply that silicate precipitation was a major sink of seawater iron and silica before the Great Oxidation Event and, because of the reactivity of nanoparticle surfaces, may also have influenced the transport and geochemical cycling of trace metals and nutrients. Our hypothesis that the basic building blocks of BIFs were predominantly iron-silicate muds rather than iron oxides and/or hydroxides may lead to new insights into seawater chemistry on the early Earth and the role of biology in the deposition of BIFs.…”
Get full text

Disequilibrium metamorphism of stressed lithosphere by Jamtveit, B., Austrheim, H., Putnis, Andrew

“…These changes are coupled with geodynamic processes and have first order effects on the global geochemical cycles of a large number of elements. In the presence of fluids, metamorphic reactions are fast compared to tectonically induced changes in pressure and temperature. …”
Get full text

Concentrations and chemical forms of heavy metals in some ultisols in Johore, Peninsular Malaysia by Darus, Siti Zauyah, Bokhari, Juliana, Ishak, Che Fauziah

“…The concentrations of heavy metals in soil are associated with biological and geochemical cycles and are influenced by anthropogenic activities such as agricultural practices, industrial activities and waste disposal. …”
Get full text
Get full text

Palaeoproterozoic supercontinents and global evolution: correlations from core to atmosphere by Reddy, Steven, Evans, D.

“…Frontiers for future research include more refined modelling of Earth's thermal and geodynamic evolution, palaeomagnetic studies of geodynamo intensity and continental motions, further geochronology and tectonic syntheses at regional levels, development of new isotopic systems to constrain geochemical cycles, and continued innovation in the search for records of early life in relation to changing palaeoenvironments.…”
Get full text