Browsing Earth and Environmental Sciences by Type "Article"
Now showing items 21-40 of 69
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Ex-situ dissolution of CO2 for carbon sequestration
(Elsevier, 2013)In this paper, a model for diffusion-controlled dissolution of CO2 droplets during co-current (CO2-brine) horizontal turbulent pipe flow is presented. The objective is to evaluate the feasibility of ex-situ dissolution of ... -
An expanded shale δ98Mo record permits recurrent shallow marine oxygenation during the Neoarchean
(Elsevier, 2020-01-20)Multiple attempts have been made using the ancient shale record to track the molybdenum isotope composition (δ98Mo) of seawater during the final two-hundred million years of the Archean Eon (2.7 to 2.5 billion-years-ago, ... -
Extensive marine anoxia during the terminal Ediacaran Period
(American Association for the Advancement of Science, 2018-06-20)The terminal Ediacaran Period witnessed the decline of the Ediacara biota (which may have included many stemgroup animals). To test whether oceanic anoxia might have played a role in this evolutionary event, we measured U ... -
Fate of Adsorbed U(VI) during Sulfidization of Lepidocrocite and Hematite
(American Chemical Society, 2017-02-21)The impact on U(VI) adsorbed to lepidocrocite (gamma-FeOOH) and hematite (alpha-Fe2O3) was assessed when exposed to aqueous sulfide (S(II)(aq)) at pH 8.0. With both minerals, competition between S(-II) and U(VI) for surface ... -
Fluid-present anatexis of Neoarchean tonalite and amphibolite in the Western Shandong Province
(Elsevier, 2019-02)Metatonalite and amphibolite from the Taishan region of the Western Shandong Province in the North China Craton record c. 2.60 Ga fluid-present partial melting via the breakdown of biotite, plagioclase and quartz to produce ... -
From Source to Sink: Petrogenesis of Cretaceous Anatectic Granites from the Fosdick Migmatite-Granite Complex, West Antarctica
(Oxford University Press, 2016-07-01)Anatectic granites from the Fosdick migmatite-granite complex yield U-Pb zircon crystallization ages that range from 115 to 100Ma, with a dominant grouping at 107-100 Ma, which corresponds to the timing of dome formation ... -
Fully oxygenated water columns over continental shelves before the Great Oxidation Event
(Nature, 2019-02-25)Late Archaean sedimentary rocks contain compelling geochemical evidence for episodic accumulation of dissolved oxygen in the oceans along continental margins before the Great Oxidation Event. However, the extent of this ... -
Garnet fractionation, progressive melt loss and bulk composition variations in anatectic metabasites: Complications for interpreting the geodynamic significance of TTGs
(Elsevier, 2020-05)Tonalite-trondhjemite-granodiorite (TTG) suites constitute a large proportion of the Archean geological record; however, the geodynamic processes that generated them, and Archean continental crust in general, remain a ... -
Genesis of a giant Paleoproterozoic strata-bound magnesite deposit: Constraints from Mg isotopes
(Elsevier, 2016-08-01)Giant strata-bound magnesite deposits are absent in modern and most Phanerozoic sedimentary environments but occur predominantly in Precambrian strata. These deposits may have formed directly through precipitation of evolved ... -
Geophysical response to simulated methane migration in groundwater based on a controlled injection experiment in a sandy unconfined aquifer
(Elsevier, 2019-09)Geophysical methods have the capacity to detect and characterize gas-phase dynamics in groundwater. Suitable methods can be deployed at surface or within boreholes depending on the required depth of investigation, ... -
Gibbs Energy Dynamic Yield Method (GEDYM): Predicting microbial growth yields under energy-limiting conditions
(Elsevier, 2018-11-15)Biomass-explicit biogeochemical models assign microbial growth yields (Y) using values measured in the laboratory or predicted using thermodynamics-based methods. However, Y values are rarely measured under the low energy ... -
Good Golly, Why Moly? THE STABLE ISOTOPE GEOCHEMISTRY OF MOLYBDENUM
(Mineralogical Society of America, 2017-01-01)No abstract available. -
Improving the efficiency of Monte Carlo Bayesian calibration of hydrologic models via model pre-emption
(International Water Association, 2015-09-01)Bayesian inference via Markov Chain Monte Carlo (MCMC) sampling and sequential Monte Carlo (SMC) sampling are popular methods for uncertainty analysis in hydrological modelling. However, application of these methodologies ... -
Inverse correlation between the molybdenum and uranium isotope compositions of Upper Devonian black shales caused by changes in local depositional conditions rather than global ocean redox variations
(Elsevier, 2020-10-15)Coupled Mo-U isotope data from the Upper Devonian Kettle Point Formation (Ontario, Canada) provide a cautionary tale regarding interpretation of global ocean redox conditions using data from euxinic black shales. In the ... -
Iron Isotope Fractionations Reveal a Finite Bioavailable Fe Pool for Structural Fe(III) Reduction in Nontronite
(American Chemical Society, 2017-08-16)We report on stable Fe isotope fractionation during microbial and chemical reduction of structural Fe(III) in nontronite NAu-1. Fe-56/Fe-54 fractionation factors between aqueous Fe(II) and structural Fe(III) ranged from ... -
Marine redox conditions during deposition of Late Ordovician and Early Silurian organic-rich mudrocks in the Siljan ring district, central Sweden
(Elsevier, 2017-05-10)The Late Ordovician Period witnessed the second largest mass extinction in the Phanerozoic Eon and the Hirnantian glaciation. To infer ocean redox conditions across the Ordovician-Silurian transition, we measured the U (as ... -
Mercury distribution and speciation in biochar particles reacted with contaminated sediment up to 1030days: A synchrotron- based study
(Elsevier, 2019-04-20)A previous long-term microcosm experiment showed mercury (Hg) in the aqueous phase of contaminated sediment was effectively stabilized through the addition of biochar. The present study focuses on the application of ... -
Methane gas transport in unconfined aquifers: A numerical sensitivity study of a controlled release experiment at CFB Borden
(Elsevier, 2019-08)Subsurface leakage of natural gas from petroleum wells can impact freshwater aquifers. Accurate prediction of gas migration in the subsurface will depend on knowledge of permeability, porosity, and flow system conditions. ... -
A Model for the Oceanic Mass Balance of Rhenium and Implications for the Extent of Proterozoic Ocean Anoxia
(Elsevier, 2018-04-15)Emerging geochemical evidence suggests that the atmosphere-ocean system underwent a significant decrease in O2 content following the Great Oxidation Event (GOE), leading to a mid-Proterozoic ocean (ca. 2.0–0.8 Ga) with ... -
Modeling of carbon dioxide dissolution in an injection well for geologic sequestration in aquifers
(Elsevier, 2021-04-15)Carbon dioxide (CO2) sequestration is considered to be one of the most effective technologies of mitigating greenhouse gas emissions. In this technology, single phase supercritical CO2 is injected into an underground ...