Browsing Geochemie, Mineralogie, Petrologie by Issue Date
Now showing items 21-40 of 395
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Greigite (Fe3S4) Formation in Artificial Sediments via Solid‐State Transformation of Lepidocrocite
; ; (Geochemistry, Geophysics, Geosystems, 2022-08-12)
Greigite (Fe3S4) is a ferrimagnetic iron‐sulfide mineral that forms in sediments during diagenesis. Greigite growth can occur diachronously within a stratigraphic profile, complicating or overprinting environmental and ... -
High‐resolution XEOL spectroscopy setup at the X‐ray absorption spectroscopy beamline P65 of PETRA III
(Journal of Synchrotron Radiation, 2022-08-11)A newly designed setup to perform steady‐state X‐ray excited optical luminescence (XEOL) spectroscopy and simultaneous XEOL and X‐ray absorption spectroscopy characterization at beamline P65 of PETRA III is described. The ... -
Incomplete Crack Sealing Causes Localization of Fracturing in Hydrothermal Quartz Veins
; ; (Geophysical Research Letters, 2022-08-10)
Cyclic microfracturing and epitaxial crystal growth have long been recognized in crack‐seal veins, but an understanding of a single crack‐seal cycle is still missing. Here we present a phase‐field model that includes both ... -
Identifying Dominant Processes in Time and Space: Time‐Varying Spatial Sensitivity Analysis for a Grid‐Based Nitrate Model
; ; ; (Water Resources Research, 2022-08-04)
Distributed models have been increasingly applied at finer spatiotemporal resolution. However, most diagnostic analyses aggregate performance measures in space or time, which might bias subsequent inferences. Accordingly, ... -
Non‐exchangeable stable hydrogen isotope ratios in clay minerals and soil clay fractions: A method test
; ; ; (European Journal of Soil Science, 2022-08-04)
Stable hydrogen isotope ratios (δ2H values) in structural hydroxyl groups of pedogenic clay minerals are inherited from the surrounding water at the time of their formation. Only non‐exchangeable H preserves the environmental ... -
Multi‐episodic formation of baddeleyite and zircon in polymetamorphic anorthosite and rutile‐bearing ilmenitite from the Chiapas Massif Complex, Mexico
; ; (Journal of Metamorphic Geology, 2022-07-20)
Massif‐type anorthosite and comagmatic associations of rutile‐bearing ilmenitite (RBI) and oxide‐apatite‐rich amphibolite (OARA) from the Chiapas Massif Complex (CMC) in southeastern Mexico display a protracted billion‐year ... -
MAGEMin, an Efficient Gibbs Energy Minimizer: Application to Igneous Systems
; ; ; (Geochemistry, Geophysics, Geosystems, 2022-07-18)
Prediction of stable mineral equilibria in the Earth's lithosphere is critical to unravel the tectonomagmatic history of exposed geological sections. While the recent advances in geodynamic modeling allow us to explore the ... -
Analytical Artefacts Preclude Reliable Isotope Ratio Measurement of Internal Water in Coral Skeletons
; ; ; ; ; ; ; ; ; (Geostandards and Geoanalytical Research, 2022-07-12)
Internal water in cold‐water and tropical coral skeletons was extracted and measured for its oxygen and hydrogen isotope ratios. Water was extracted by crushing pieces of coral hard tissue in a percussion device connected ... -
Deepening the Late Quaternary's Deep Ocean Carbon Mysteries
(Geophysical Research Letters, 2022-07-06)
Changes to the carbon content of the deep ocean, the largest reservoir in the surficial carbon cycle, are capable of altering atmospheric carbon dioxide concentrations and thereby Earth's climate. While the role of the ... -
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover Along the Eastern Continental Shelf of the Antarctic Peninsula
; ; ; ; (Journal of Geophysical Research: Oceans, 2022-06-28)
Rapid and profound climatic and environmental changes have been predicted for the Antarctic Peninsula with so far unknown impact on the biogeochemistry of the continental shelves. In this study, we investigate benthic ... -
Variability in the Concentration of Lithium in the Indo‐Pacific Ocean
; ; ; ; ; ; (Global Biogeochemical Cycles, 2022-06-22)
Lithium has limited biological activity and can readily replace aluminium, magnesium and iron ions in aluminosilicates, making it a proxy for the inorganic silicate cycle and its potential link to the carbon cycle. Data ... -
The Subducting Slab as a Chromatographic Column: Regimes of Sub‐Solidus Mass Transport as a Function of Lithospheric Hydration State, With Special Reference to the Fate of Carbonate
; (Journal of Geophysical Research: Solid Earth, 2022-05-31)
We investigate the chemical budget of subduction zones at sub‐solidus conditions using a thermodynamic‐numerical simulation in which all major rock components are treated as soluble and potentially mobile in aqueous fluids. ... -
Robust approaches for model‐free small‐angle scattering data analysis
(Journal of Applied Crystallography, 2022-05-28)The small‐angle neutron scattering data of nanostructured magnetic samples contain information regarding their chemical and magnetic properties. Often, the first step to access characteristic magnetic and structural length ... -
Geochronology and petrogenesis of granitoids and associated mafic enclaves from Ghohroud in the Urumieh–Dokhtar Magmatic Arc (Iran): Evidence for magma mixing during the closure of the Neotethyan Ocean
;; ; ; ; ; (Geological Journal, 2022-05-18)
The Ghohroud granitoids (GG), containing mafic microgranular enclaves (MMEs) are located in the central part of the Urumieh‐Dokhtar Magmatic Arc (UDMA) in central Iran. They are associated with the subduction‐related ... -
Arctic – Atlantic Exchange of the Dissolved Micronutrients Iron, Manganese, Cobalt, Nickel, Copper and Zinc With a Focus on Fram Strait
; ; ; ; ; ; ; ; ; ; ; ; (Global Biogeochemical Cycles, 2022-05-16)
The Arctic Ocean is considered a source of micronutrients to the Nordic Seas and the North Atlantic Ocean through the gateway of Fram Strait (FS). However, there is a paucity of trace element data from across the Arctic ... -
Asteroid 2008 TC3, not a polymict ureilitic but a polymict C1 chondrite parent body? Survey of 249 Almahata Sitta fragments
; ; ; ; ; ; ; ; ; ; ; ; (Meteoritics & Planetary Science, 2022-05-14)
On October 7, 2008, the asteroid 2008 TC3 exploded as it entered the Earth’s atmosphere, producing significant dust (in the atmosphere) and delivering thousands of stones in a strewn field in Sudan, collectively known as ... -
Clay fraction properties and grassland management imprint on soil organic matter composition and stability at molecular level
; ; ; ; (Soil Use and Management, 2022-05-07)
The dynamics of soil carbon in grassland are partly determined by soil organic matter (SOM) composition. However, it remains unclear which role grassland management plays in the interplay between SOM composition and carbon ... -
Microbially promoted calcite precipitation in the pelagic redoxcline: Elucidating the formation of the turbid layer
; ; ; ; ; ; ; ; ; ; (Geobiology, 2022-05-05)
Large bell‐shaped calcite formations called “Hells Bells” were discovered underwater in the stratified cenote El Zapote on the Yucatán Peninsula, Mexico. Together with these extraordinary speleothems, divers found a white, ... -
Temporal evolution of headwall erosion rates derived from cosmogenic nuclide concentrations in the medial moraines of Glacier d'Otemma, Switzerland
; ; ; (Earth Surface Processes and Landforms, 2022-05-03)
Climate change affects the stability and erosion of high‐alpine rock walls above glaciers (headwalls) that deliver debris to glacier surfaces. Since supraglacial debris in the ablation zone alters the melt behaviour of the ... -
Formation of fused aggregates under long‐term microgravity conditions aboard the ISS with implications for early solar system particle aggregation
; ; ; ; ; ; ; ; ; (Meteoritics & Planetary Science, 2022-04-21)
In order to gain further insights into early solar system aggregation processes, we carried out an experiment on board the International Space Station, which allowed us to study the behavior of dust particles exposed to ...
