Results 41 to 50 of about 5,408 (193)

Spatial and temporal distribution of geochemical elements and their processes in different size fractions–Miri River (NW Borneo)

Kuwait Journal of Science
The toxicity, persistence, and propensity for accumulation of metals in aquatic environments have raised significant concerns globally. Expansion of urbanization with the growth of industrial and agricultural sectors in Miri City results in a high ...
Fiona Bassy William View in Scopus, Prasanna Mohan Viswanathan, Nagarajan Ramasamy   +2 more
doaj   +1 more source

Arctic freshwater fluxes: sources, tracer budgets and inconsistencies [PDF]

The Cryosphere, 2019
The net rate of freshwater input to the Arctic Ocean has been calculated in the past by two methods: directly, as the sum of precipitation, evaporation and runoff, an approach hindered by sparsity of measurements, and by the ice and ocean budget method,
A. Forryan, S. Bacon, T. Tsubouchi, S. Torres-Valdés, A. C. Naveira Garabato   +4 more
doaj   +1 more source

Geochemistry and Geochronology of Magmatic Rocks in Southwestern and Northeastern Cambodia: Implications for the Tectonic Evolution and Metallogenesis of the Loei Fold Belt

Geological Journal, EarlyView.
The composition of intrusive rocks suggests that the magma was likely generated in a subduction‐related setting. The arc crustal thickness in the Phnom Sro Ngam and Halo Prospects was probably < 40 km during emplacement. Zircon U–Pb age range indicates a correlation with Loei Fold Belt magmatic activity.
Sirisokha Seang, Khin Zaw, Kakda Kret, Ivan Belousov, Kotaro Yonezu, Koichiro Watanabe, Charles Makoundi   +6 more
wiley   +1 more source

Influence of particle-size on geochemical distribution of stream sediments in the Lese river catchment, southern Italy

Biotechnologie, Agronomie, Société et Environnement, 2013
This study was carried out in a river catchment in southern Italy to determine some possible relationships between the distribution of chemical elements and size fractions in stream sediments.
Guagliardi, I., Apollaro, C., Scarciglia, F., De Rosa, R.   +3 more
doaj  

Late Pleistocene Volcanic Rocks From Tengchong Volcanic Field at SE Tibetan Plateau: Constraints on Petrogenesis and Mantle and Crustal Processes

Geological Journal, EarlyView.
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley   +1 more source

Química de elementos-traço nos sedimentos do Lago do Parú (Manacapuru - Amazonas), sob influência do pulso de inundação do baixo Rio Solimões Trace elements chemical in Lago do Parú (Manacapuru - Amazonas) sediments, under Lower Solimões River flood pulse influence

Acta Amazonica, 2008
O objetivo deste estudo foi determinar as concentrações totais e em frações geoquímicas de Fe, Mn, Co, Cu e Zn em sedimentos, coletados nos períodos de seca (2005) e cheia (2006) do Lago do Parú.
Adriana Koumrouyan, Genilson Pereira Santana   +1 more
doaj   +1 more source

A Reassessment of Petrochemistry of ~1.2 Ga Tonalitic Rocks of the Northern Tugela Terrane, Natal Metamorphic Belt, South Africa: Further Constraints on the Evolution of This Belt

Geological Journal, EarlyView.
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta, Saumitra Misra, Thembiso O. Basupi   +2 more
wiley   +1 more source

Characteristics of Gravity Flow Deposits in the Benin Basin (Benin) and Implications for Oil and Gas Exploration

Geological Journal, EarlyView.
This study reveals that the underexplored Benin Basin features a narrow shelf and steep slope, which promoted the development of multi‐phase, stacked channel‐lobe complexes. These gravity flow deposits, further enhanced by bottom current reworking, reveal a significant undiscovered Upper Cretaceous stratigraphic play with considerable petroleum ...
Liu Zuodong, Wen Zhixin, Song Chenpeng, Wang Xueling, Shen Yiping   +4 more
wiley   +1 more source

Mineralogy, magnetic susceptibility and geochemistry of Fe-rich Oxisols developed from several parent materials

Scientia Agricola
: Fe-rich Oxisols on mafic rocks in Brazil generally have high magnetic susceptibility with high contents of some trace elements. These are taxonomically similar soils; however, differences in magnetic and geochemical properties may affect agricultural ...
Danilo de Lima Camêlo, João Carlos Ker, Maurício Paulo Ferreira Fontes, Antonio Carlos Saraiva da Costa, Marcelo Metri Corrêa, Matthias Leopold   +5 more
doaj   +1 more source

Local Structures of Se and Br in Cretaceous–Paleogene Boundary Sediments and Concentration Effects of Ferrihydrite Originating From Impact Ejecta

Geological Journal, EarlyView.
Chemical states of Se and Br atoms in the KPg boundary sediments from Stevns Klint were studied using XAFS spectroscopy. The high concentrations of Se4+ could become an index of the degree to which the global environment was soiled with dust and ash derived from impact ejecta or volcanic eruptions.
Kei‐ichiro Murai, Akira Yoshiasa, Ginga Kitahara, Makoto Tokuda, Satoko Ishimaru, Toshihiro Moriga   +5 more
wiley   +1 more source