Browsing Research Articles (Earth Sciences) by Title
Now showing items 1-20 of 29
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Atmospheric deposition fluxes over the Atlantic Ocean : a GEOTRACES case study
(Copernicus Publications, 2019-04-11)Atmospheric deposition is an important source of micronutrients to the ocean, but atmospheric deposition fluxes remain poorly constrained in most ocean regions due to the limited number of field observations of wet and dry ... -
Characterization of coloured gemstones by X-ray micro computed tomography
(MDPI, 2021-02-08)The monetary value of gemstones is based on five variables: rarity, cut, weight, color and clarity. The latter refers to internal impurities and defects. Fashion may also dictate demand and price. To enhance some of these ... -
Characterization of xenotime from Datas (Brazil) as a potential reference material for in situ U-Pb geochronology
(Wiley Online Library, 2018-07-16)This study investigates five megacrysts of xenotime (XN01, XN02, XN03, XN04, and XN05) as potential reference materials (RMs) for U‐Pb geochronology. These crystals belong to a 300 g xenotime assortment, collected from ... -
Controls on redox-sensitive trace metals in the Mauritanian oxygen minimum zone
(Copernicus Publications, 2019-11-05)The availability of the micronutrient iron (Fe) in surface waters determines primary production, N2 fixation, and microbial community structure in large parts of the world's ocean, and thus it plays an important role in ... -
Correlation between knowledge of HIV, attitudes and perceptions of HIV and a willingness to test for HIV at a regional hospital in KwaZulu-Natal, South Africa
(AOSIS Publishing, 2012-07)Background: With millions of South Africans infected with human immunodeficiency virus (HIV) and less than 10% of the population aware of their HIV status, HIV counselling and testing (HCT) is the first step in any attempt ... -
Coupled zircon-rutile U-Pb chronology : LA ICP-MS dating, geological significance and applications to Sediment Provenance in the Eastern Himalayan-Indo-Burman Region
(MDPI, 2019-11-05)U-Pb dating by LA ICP-MS is one of the most popular and successful isotopic techniques available to the Earth Sciences to constrain timing and rates of geological processes thanks to its high spatial resolution, good ... -
Developing a 3D mineral texture quantification method of drill core for geometallurgy
(Southern African Institute of Mining and Metallurgy, 2019-04)Mineral texture is a critical factor which controls ore variability and is an important attribute in geometallurgy. In relation to downstream processes, it affects the fracture pattern during breakage, where rock strength ... -
Developing autonomous observing systems for micronutrient trace metals
(Frontiers Media, 2019-02-21)Trace metal micronutrients are integral to the functioning of marine ecosystems and the export of particulate carbon to the deep ocean. Although much progress has been made in mapping the distributions of metal micronutrients ... -
Diminutive fleet-footed tyrannosauroid narrows the 70-million-year gap in the North American fossil record
(Springer Nature, 2019-02-21)To date, eco-evolutionary dynamics in the ascent of tyrannosauroids to top predator roles have been obscured by a 70-million-year gap in the North American (NA) record. Here we report discovery of the oldest Cretaceous NA ... -
Dissolved iron in the North Atlantic Ocean and Labrador Sea along the GEOVIDE section (GEOTRACES section GA01)
(2020-02-21)Dissolved Fe (DFe) samples from the GEOVIDE voyage (GEOTRACES GA01, May–June 2014) in the North Atlantic Ocean were analysed using a SeaFAST-picoTM coupled to an Element XR HR-ICP-MS and provided interesting insights on ... -
Distributive rainfall–runoff modelling to understand runoff-to-baseflow proportioning and its impact on the determination of reserve requirements of the Verlorenvlei Estuarine lake, West coast, South Africa
(European Geosciences Union, 2019-06-24)River systems that support high biodiversity profiles are conservation priorities worldwide. Understanding river ecosystem thresholds to low-flow conditions is important for the conservation of these systems. While climatic ... -
Diversity of burial rates in convergent settings decreased as Earth aged
(Springer Nature, 2016)The evolution and the growth of the continental crust is inextricably linked to the evolution of Earth’s geodynamic processes. The detrital zircon record within the continental crust, as well as the isotopic composition ... -
The emergence of modern sea ice cover in the Arctic Ocean
(Springer Nature, 2014-07)Arctic sea ice coverage is shrinking in response to global climate change and summer ice-free conditions in the Arctic Ocean are predicted by the end of the century. The validity of this prediction could potentially be ... -
Estimation of groundwater recharge via percolation outputs from a rainfall / runoff model for the Verlorenvlei estuarine system, West coast, South Africa
(Elsevier, 2018)Wetlands are conservation priorities worldwide, due to their high biodiversity and productivity, but are under threat from agricultural and climate change stresses. To improve the water management practices and resource ... -
A global compilation of over 13 000 dissolved iron measurements : focus on distributions and processes in the Southern Ocean
(Copernicus Publications, 2011-11)Due to its importance as a limiting nutrient for phytoplankton growth in large regions of the world’s oceans, ocean water column observations of concentration of the tracemetal iron (Fe) have increased markedly over ... -
Gold exploration in two and three dimensions : improved and correlative insights from microscopy and X-Ray computed tomography
(MDPI, 2020)Abstract: In this contribution, we highlight a correlative approach in which three-dimensional structural/positional data are combined with two dimensional chemical and mineralogical data to understand a complex orogenic ... -
Influence of water availability in the distributions of branched glycerol dialkyl glycerol tetraether in soils of the Iberian Peninsula
(European Geosciences Union, 2014)The combined application of the MBT (degree of methylation) and CBT (degree of cyclization) indices, based on the distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in soils, has been proposed as a ... -
Inputs and processes affecting the distribution of particulate iron in the North Atlantic along the GEOVIDE (GEOTRACES GA01) section
(Copernicus Publications, 2019-04-12)The aim of the GEOVIDE cruise (May–June 2014, R/V Pourquoi Pas?) was to provide a better understanding of trace metal biogeochemical cycles in the North Atlantic Ocean. As marine particles play a key role in the global ... -
Introduction to the French GEOTRACES North Atlantic Transect (GA01) : GEOVIDE cruise
(European Geosciences Union, 2018-11-29)The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June ... -
Iron-rich nanoparticles in natural aquatic environments
(MDPI, 2019-05-11)Naturally-occurring iron nanoparticles constitute a quantitatively-important and biogeochemically-active component of the broader Earth ecosystem. Yet detailed insights into their chemical speciation is sparse compared ...