Auflistung Geochemie, Mineralogie, Petrologie nach Titel
Anzeige der Dokumente 267-286 von 567
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Late Holocene to Recent aragonite-cemented transgressive lag deposits in the Abu Dhabi lagoon and intertidal sabkha
(Sedimentology, 2020)Modern cemented intervals (beachrock, firmgrounds to hardgrounds and concretionary layers) form in the lagoon and intertidal sabkha of Abu Dhabi. Seafloor lithification actively occurs in open, current-swept channels in ... -
Lateral variations in the Unit 7–8 boundary zone of the Rum Eastern Layered Intrusion, NW Scotland: implications for the origin and timing of Cr-spinel seam formation
(Contributions to Mineralogy and Petrology, 2020-09-02)The Rum Layered Suite, NW Scotland, hosts Cr-spinel seams at the bases of peridotite–troctolite macro-rhythmic units in the eastern portion of the intrusion. Here, we present detailed field observations together with ... -
Latest Carboniferous to early Permian volcano-stratigraphic evolution in Central Europe: U–Pb CA–ID–TIMS ages of volcanic rocks in the Thuringian Forest Basin (Germany)
(International Journal of Earth Sciences, 2020-11-23)Mainly acidic Stephanian to early Permian volcanic rocks and intercalated sediments accumulated in the Thuringian Forest Basin (TFB) in central Germany to a total thickness of ca. 2000 m. This basin offers a wide range of ... -
Layer groups: Brillouin‐zone and crystallographic databases on the Bilbao Crystallographic Server
(Acta Crystallographica Section A, 2021-09-24)The section of the Bilbao Crystallographic Server (https://www.cryst.ehu.es/) dedicated to subperiodic groups contains crystallographic and Brillouin‐zone databases for the layer groups. The crystallographic databases ... -
Li-Co–Ni-Mn-(REE) veins of the Western Erzgebirge, Germany—a potential source of battery raw materials
(Mineralium Deposita, 2021-06-25)Situated in the western Erzgebirge metallogenetic province (Vogtland, Germany), the Eichigt prospect is associated with several quartz-Mn-Fe-oxyhydroxide veins that are exposed at surface. Bulk-rock geochemical assays of ... -
Limited angle tomography for transmission X-ray microscopy using deep learning
(Journal of Synchrotron Radiation, 2020)In transmission X-ray microscopy (TXM) systems, the rotation of a scanned sample might be restricted to a limited angular range to avoid collision with other system parts or high attenuation at certain tilting angles. Image ... -
Linking the Dissolved and Particulate Domain of Organic Carbon in Inland Waters
(Journal of Geophysical Research: Biogeosciences, 2021-05-11)Organic carbon (OC) in inland waters is found in either dissolved or particulate states, each contributing differently to carbon cycling through state‐specific forms of transport, processing, and mineralization. Degradation ... -
Lithium and Sr isotopic composition of salar deposits in the Central Andes across space and time: the Salar de Pozuelos, Argentina
(Mineralium Deposita, 2021-07-07)The Central Andes of South America host the largest known lithium resources in a confined area, but the primary lithium sources of the salar deposits and the mobilisation process of lithium are still a matter of speculation. ... -
Long‐Period Astronomical Forcing of Westerlies' Strength in Central Asia During Miocene Climate Cooling
(Paleoceanography and Paleoclimatology, 2019-11-29)The continental expression of global cooling during the Miocene Climate Transition in Central Asia is poorly documented, as the tectonically active setting complicates the correlation of Neogene regional and global climatic ... -
Long‐term intercomparison of two pCO2 instruments based on ship‐of‐opportunity measurements in a dynamic shelf sea environment
(Limnology and Oceanography: Methods, 2020-12-28)The partial pressure of carbon dioxide (pCO2) in surface seawater is an important biogeochemical variable because, together with the pCO2 in the atmosphere, it determines the direction of air–sea carbon dioxide exchange. ... -
Long‐Term Nitrate Trajectories Vary by Season in Western European Catchments
(Global Biogeochemical Cycles, 2021-09-12)Human alteration of nutrient cycles has caused persistent and widespread degradation of water quality around the globe. In many regions, including Western Europe, elevated nitrate (NO3−) concentration in surface waters ... -
Lösungskinetik von Gips und Anhydrit
(Univ. Bremen, 2002)The dissolution kinetics of gypsum and anhydrite have been measured under various conditions. For gypsum an almost linear rate equation R=ks1(1-c/ceq)n1 is valid, where R is the surface rate, n1 1 is the kinetics order, ... -
Lu–Hf geochronology of ultra-high-pressure eclogites from the Tromsø-Nappe, Scandinavian Caledonides: evidence for rapid subduction and exhumation
(International Journal of Earth Sciences, 2020-05-01)Geochronology of ultra-high-pressure metamorphic rocks is able to constrain the timing and rates of subduction-zone processes. Lu–Hf garnet dating has the potential to yield information about the timing of the prograde ... -
Machine learning for scattering data: strategies, perspectives and applications to surface scattering
(Journal of Applied Crystallography, 2023-01-24)Machine learning (ML) has received enormous attention in science and beyond. Discussed here are the status, opportunities, challenges and limitations of ML as applied to X‐ray and neutron scattering techniques, with an ... -
Mafic explosive volcanism at Llaima Volcano: 3D x-ray microtomography reconstruction of pyroclasts to constrain shallow conduit processes
(Bulletin of Volcanology, 2021-12-06)Mafic volcanic activity is dominated by effusive to mildly explosive eruptions. Plinian and ignimbrite-forming mafic eruptions, while rare, are also possible; however, the conditions that promote such explosivity are still ... -
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 ... -
Manual measurement of angles in backscattered and transmission Kikuchi diffraction patterns
(Journal of Applied Crystallography, 2020)A historical tool for crystallographic analysis is provided by the Hilton net, which can be used for manually surveying the crystal lattice as it is manifested by the Kikuchi bands in a gnomonic projection. For a quantitative ... -
Mapping the 3D position of battery cathode particles in Bragg coherent diffractive imaging
(Journal of Synchrotron Radiation, 2023-02-16)In Bragg coherent diffractive imaging, the precise location of the measured crystals in the interior of the sample is usually missing. Obtaining this information would help the study of the spatially dependent behavior of ... -
Marble decay: towards a measure of marble degradation based on ultrasonic wave velocities and thermal expansion data
(Environmental Earth Sciences, 2021-05-23)Marble as ornamental and dimensional stones as well as in their natural environments show complex weathering phenomena. Physical, chemical, and biological weathering of marble are well documented. The impact of climate ... -
Measured and Simulated Carbon Dynamics in Midwestern U.S. Corn‐Soybean Rotations
(Global Biogeochemical Cycles, 2020-12-29)Corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) production dominate Midwestern U.S. agriculture and impact the regional carbon and nitrogen cycles. Sustaining soil carbon is important for corn‐soybean production ...