Browsing Geochemie, Mineralogie, Petrologie by Issue Date
Now showing items 1-20 of 395
-
Chemical Geodynamics Insights From a Machine Learning Approach
(Geochemistry, Geophysics, Geosystems, 2022-10-19)The radiogenic isotope heterogeneity of oceanic basalts is often assessed using 2D isotope ratio diagrams. But because the underlying data are at least six dimensional (87Sr/86Sr, 143Nd/144Nd, 176Hf/177Hf, and 208,207,20 ... -
Experimentally Induced Thermal Fatigue on Lunar and Eucrite Meteorites—Influence of the Mineralogy on Rock Breakdown
(Journal of Geophysical Research: Planets, 2022-10-07)Thermal fatigue has been proven to be of fundamental importance for the nature and evolution of surfaces of airless bodies in the solar system. It is a rock erosive process acting in conjunction with meteoroid bombardment. ... -
X‐ray diffraction with micrometre spatial resolution for highly absorbing samples
(Journal of Synchrotron Radiation, 2022-10-05)X‐ray diffraction with high spatial resolution is commonly used to characterize (poly)crystalline samples with, for example, respect to local strain, residual stress, grain boundaries and texture. However, the investigation ... -
HTD2: a single‐crystal X‐ray diffractometer for combined high‐pressure/low‐temperature experiments at laboratory scale
(Journal of Applied Crystallography, 2022-09-29)High‐pressure (HP) X‐ray diffraction experiments at low temperature (LT) require dedicated instruments as well as non‐standard sample environments and measuring strategies. This is especially true when helium cryogenic ... -
Domain Auto Finder (DAFi) program: the analysis of single‐crystal X‐ray diffraction data from polycrystalline samples
(Journal of Applied Crystallography, 2022-09-29)This paper presents the Domain Auto Finder (DAFi) program and its application to the analysis of single‐crystal X‐ray diffraction (SC‐XRD) data from multiphase mixtures of microcrystalline solids and powders. Superposition ... -
Spatial and temporal dynamics of water isotopes in the riverine‐marine mixing zone along the German Baltic Sea coast
(Hydrological Processes, 2022-09-28)River estuaries are characterized by mixing processes between freshwater discharge and marine water masses. Since the first are depleted in heavier stable isotopes compared with the marine realm, estuaries often show a ... -
Sediment Release in the Benguela Upwelling System Dominates Trace Metal Input to the Shelf and Eastern South Atlantic Ocean
(Global Biogeochemical Cycles, 2022-09-25)Upwelling of subsurface waters injects macronutrients (fixed N, P, and Si) and micronutrient trace metals (TMs) into surface waters supporting elevated primary production in Eastern Boundary Upwelling Regions. The eastern ... -
Developing a Laser Induced Liquid Beam Ion Desorption Spectral Database as Reference for Spaceborne Mass Spectrometers
(Earth and Space Science, 2022-09-13)Spaceborne impact ionization mass spectrometers, such as the Cosmic Dust Analyzer on board the past Cassini spacecraft or the SUrface Dust Analyzer being built for NASA's upcoming Europa Clipper mission, are of crucial ... -
A New Method for Determining Fluid Flux at High Pressures Applied to the Dehydration of Serpentinites
(Geochemistry, Geophysics, Geosystems, 2022-09-08)A new method to determine fluid flux at high pressures and temperatures has been developed and used to study serpentinites at subduction zone conditions. Drill cores of a natural antigorite‐serpentinite with a strong ... -
Site dependence of the magnetocaloric effect in Mn5−xFexSi3
(Journal of Applied Crystallography, 2022-09-06)The nuclear and magnetic structures of Mn3Fe2Si3 are investigated in the temperature range from 20 to 300 K. The magnetic properties of Mn3Fe2Si3 were measured on a single crystal. The compound undergoes a paramagnetic to ... -
Curie Temperatures and Emplacement Conditions of Pyroclastic Deposits From Popocatépetl Volcano, Mexico
(Geochemistry, Geophysics, Geosystems, 2022-08-29)Most pyroclastic deposits of Popocatépetl volcano were emplaced at high temperatures and have similar mafic to more evolved compositions, suggesting a long‐lived, interconnected magma environment. We performed a magnetic ... -
Denitrification‐Driven Transcription and Enzyme Production at the River‐Groundwater Interface: Insights From Reactive‐Transport Modeling
(Water Resources Research, 2022-08-26)Molecular‐biological data and omics tools have increasingly been used to characterize microorganisms responsible for the turnover of reactive compounds in the environment, such as reactive‐nitrogen species in groundwater. ... -
Single‐Crystal Elasticity of Antigorite at High Pressures and Seismic Detection of Serpentinized Slabs
(Geophysical Research Letters, 2022-08-26)The subduction of serpentinized slabs is the dominant process to transport “water” into Earth's mantle, and plays a pivotal role for subduction dynamics. Antigorite, the most abundant serpentine mineral in subduction ... -
Phase Stability of Al‐Bearing Dense Hydrous Magnesium Silicates at Topmost Lower Mantle Conditions: Implication for Water Transport in the Mantle
(Geophysical Research Letters, 2022-08-26)In this study, we investigated the phase stability of Al‐free and Al‐bearing superhydrous phase B (shy‐B) up to 55 GPa and 2500 K. In comparison with Al‐free shy‐B, the incorporation of 11.7 wt.% Al2O3 in shy‐B expands the ... -
Seamless Integration of the Coastal Ocean in Global Marine Carbon Cycle Modeling
(Journal of Advances in Modeling Earth Systems, 2022-08-26)We present the first global ocean‐biogeochemistry model that uses a telescoping high resolution for an improved representation of coastal carbon dynamics: ICON‐Coast. Based on the unstructured triangular grid topology of ... -
The Synergy of Data From Profiling Floats, Machine Learning and Numerical Modeling: Case of the Black Sea Euphotic Zone
(Journal of Geophysical Research: Oceans, 2022-08-24)Data from profiling floats in the Black Sea revealed complex temporal and spatial relationships between physical variables and oxygen, chlorophyll and the backscattering coefficient at 700 nm, as well as some limits in ... -
Digitization of imaging plates from Guinier powder X‐ray diffraction cameras
(Journal of Applied Crystallography, 2022-08-24)A Guinier camera equipped with an imaging plate is used to investigate and eliminate the sources of instrumental errors affecting the quality of the obtained scanned Guinier data. A program with a graphical user interface ... -
Dynamics of Greenhouse Gases (CH4 and CO2) in Meromictic Lake Burgsee, Germany
(Journal of Geophysical Research: Biogeosciences, 2022-08-19)Extraordinary amounts of greenhouse gases can be stored within the monimolimnion of meromictic lakes, that is, in the water body which is excluded from mixing events. Lake Burgsee (Thuringia, Germany) is a shallow (depth ... -
Laboratory Assessment of the Impact of Chemical Oxidation, Mineral Dissolution, and Heating on the Nitrogen Isotopic Composition of Fossil‐Bound Organic Matter
(Geochemistry, Geophysics, Geosystems, 2022-08-19)Fossil‐bound organic material holds great potential for the reconstruction of past changes in nitrogen (N) cycling. Here, with a series of laboratory experiments, we assess the potential effect of oxidative degradation, ... -
Particle‐Phase Uptake and Chemistry of Highly Oxygenated Organic Molecules (HOMs) From α‐Pinene OH Oxidation
(Journal of Geophysical Research: Atmospheres, 2022-08-16)Secondary organic aerosol (SOA) forms a major part of the tropospheric submicron particle mass. Still, the exact formation mechanisms of SOA have remained elusive. It is now admitted that highly oxygenated organic molecules ...