Auflistung Geochemie, Mineralogie, Petrologie nach Titel
Anzeige der Dokumente 402-421 von 562
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Sampling soil water along the pF curve for δ2H and δ18O analysis
(Hydrological Processes, 2020)Soil water stable isotopes are widely used across disciplines (e.g., hydrology, ecology, soil science, and biogeochemistry). However, the full potential of stables isotopes as a tool for characterizing the origin, flow ... -
Sampling, separation, and quantification of N‐acyl homoserine lactones from marine intertidal sediments
(Limnology and Oceanography: Methods, 2021-01-20)N‐acyl homoserine lactones (AHLs) are molecules produced by many Gram‐negative bacteria as mediators of cell‐cell signaling in a mechanism known as quorum sensing (QS). QS is widespread in marine bacteria regulating diverse ... -
Schwingungsspektroskopie von OH-führenden Defekten in Granat
(Univ. Berlin, 1999) -
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 ... -
Seasonal Carbon Dynamics in the Near‐Global Ocean
(Global Biogeochemical Cycles, 2020-12-23)The seasonal cycle represents one of the largest signals of dissolved inorganic carbon (DIC) in the ocean, yet these seasonal variations are not well established at a global scale. Here, we present the Mapped Observation‐Based ... -
Seasonality of Organic Matter Degradation Regulates Nutrient and Metal Net Fluxes in a High Energy Sandy Beach
(Journal of Geophysical Research: Biogeosciences, 2020)During seawater circulation in permeable intertidal sands, organic matter degradation alters the composition of percolating fluids and remineralization products discharge into surficial waters. Concurrently, coastal seawater ... -
Secondary Minerals Drive Extreme Lithium Isotope Fractionation During Tropical Weathering
(Journal of Geophysical Research: Earth Surface, 2022-02-15)Lithium isotopes are used to trace weathering intensity, but little is known about the processes that fractionate them in highly weathered settings, where secondary minerals play a dominant role in weathering reactions. ... -
Sectioning effects of porphyritic chondrules: Implications for the PP/POP/PO classification and correcting modal abundances of mineralogically zoned chondrules
(Meteoritics & Planetary Science, 2020)Mineralogically zoned chondrules are a common chondrule type in chondrites. They consist of olivine cores, surrounded by low-Ca pyroxene rims. By serial sectioning porphyritic chondrules from carbonaceous, ordinary, and ... -
Sediment Properties Drive Spatial Variability of Potential Methane Production and Oxidation in Small Streams
(Journal of Geophysical Research: Biogeosciences, 2020)Emissions of the potent greenhouse gas methane (CH4) from streams and rivers are a significant component of global freshwater methane emissions. The distribution of CH4 production and oxidation within stream sections and ... -
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 ... -
Sedimentological and carbonate isotope signatures to identify fluvial processes and catchment changes in a supposed impact ejecta‐dammed lake (Miocene, Germany)
(Sedimentology, 2021-06-20)The identification and distinction of fluvial from lacustrine deposits and the recognition of catchment changes are crucial for the reconstruction of climate changes in terrestrial environments. The investigated drill core ... -
Separation of the inelastic and elastic scattering in time‐of‐flight mode on the pinhole small‐angle neutron scattering diffractometer KWS‐2
(Journal of Applied Crystallography, 2021-07-30)To study and control the incoherent inelastic background in small‐angle neutron scattering, which makes a significant contribution to the detected scattering from hydrocarbon systems, the KWS‐2 small‐angle neutron scattering ... -
Serpentinization-driven H2 production from continental break-up to mid-ocean ridge spreading: unexpected high rates at the West Iberia margin
(2021)Molecular hydrogen (H2) released during serpentinization of mantle rocks is one of the main fuels for chemosynthetic life. Processes of H2 production at slow-spreading mid-ocean ridges (MORs) have received much attention ... -
Shallow‐marine carbonate cementation in Holocene segments of the calcifying green alga Halimeda
(Sedimentology, 2021-09-15)Early‐diagenetic cementation of tropical carbonates results from the combination of numerous physico‐chemical and biological processes. In the marine phreatic environment it represents an essential mechanism for the ... -
Shock-induced formation of wüstite and fayalite in a magnetite-quartz target rock
(Meteoritics & Planetary Science, 2019)Projectile–target interactions as a result of a large bolide impact are important issues, as abundant extraterrestrial material has been delivered to the Earth throughout its history. Here, we report results of shock-recovery ... -
Silicon and iron isotopes in components of enstatite chondrites: Implications for metal–silicate–sulfide fractionation in the solar nebula
(Meteoritics & Planetary Science, 2023-06-28)Silicon and iron isotope compositions of different physically separated components of enstatite chondrites (EC) were determined in this study to understand the role of nebular and planetary scale events in fractionating ... -
Silicon Isotopes in an EMIC's Ocean: Sensitivity to Runoff, Iron Supply, and Climate
(Paleoceanography and Paleoclimatology, 2020)The isotopic composition of Si in biogenic silica (BSi), such as opal buried in the oceans' sediments, has changed over time. Paleorecords suggest that the isotopic composition, described in terms of δ30Si, was generally ... -
Simulated Future Trends in Marine Nitrogen Fixation Are Sensitive to Model Iron Implementation
(Global Biogeochemical Cycles, 2022-02-24)Biological nitrogen fixation is an important oceanic nitrogen source, potentially stabilizing marine fertility in an increasingly stratified and nutrient‐depleted ocean. Iron limitation of low latitude primary producers ... -
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 ... -
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 ...