Auflistung Geochemie, Mineralogie, Petrologie nach Titel
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H2O in omphacite of quartz and coesite eclogite from Erzgebirge and Fichtelgebirge, Germany
(Journal of Metamorphic Geology, 2021-12-13)Major and trace elements in omphacite, including hydrogen, were determined in eclogites from two Variscan basement complexes in Germany: Erzgebirge (EG) and Fichtelgebirge (FG). Erzgebirge eclogite is derived from three ... -
Hard X‐ray full‐field nanoimaging using a direct photon‐counting detector
(Journal of Synchrotron Radiation, 2023-02-01)Full‐field X‐ray nanoimaging is a widely used tool in a broad range of scientific areas. In particular, for low‐absorbing biological or medical samples, phase contrast methods have to be considered. Three well established ... -
Hf-W chronology of a macrochondrule from the L5/6 chondrite Northwest Africa 8192
(Meteoritics & Planetary Science, 2020)A large, igneous-textured, and 2 cm-sized spherical object from the L5/6 chondrite NWA 8192 was investigated for its chemical composition, petrography, O isotopic composition, and Hf-W chronology. The petrography and ... -
Hidden in plain sight: A microanalytical study of a Middle Stone Age ochre piece trapped inside a micromorphological block sample
(Geoarchaeology, 2020-12-15)A complete Middle Stone Age ochre piece was unintentionally collected and fully preserved within a micromorphological block sample intended to characterise a 74 ± 3 ka occupation horizon at Blombos Cave, South Africa. ... -
High field strength element systematics and Lu-Hf & Sm-Nd garnet geochronology of orogenic eclogites
(Univ. Frankfurt (Main), 2008)Concerning the Bulk Silicate Earth (BSE), the depleted mantle and the continental crust are thought to balance the budget of refractory and lithophile elements, resulting in complementary trace element patterns. However, ... -
High-Resolution Imaging of Texture and Microstructure by the Moving Detector Method
(Textures and Microstructures, 2003)In order to describe texture and microstructure of a polycrystalline material completely, crystal orientation g={?1F?2} must be known in all points x={x1?x2?x3} of the material. This can be achieved by locationresolved ... -
High‐resolution facies analysis of a coastal sabkha in the eastern Gulf of Salwa (Qatar): A spatio‐temporal reconstruction
(Sedimentology, 2021-10-12)Abstract Sabkhas are key landforms along the southern coast of the Arabian Gulf and represent modern analogues for depositional and diagenetic processes controlling properties and quality of ancient hydrocarbon‐bearing ... -
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 ... -
High‐temperature treatments of niobium under high vacuum, dilute air‐ and nitrogen‐atmospheres as investigated by in situ X‐ray absorption spectroscopy
(Journal of Synchrotron Radiation, 2020-12-18)Niobium metal foils were heat‐treated at 900°C under different conditions and in situ investigated with time‐resolved X‐ray absorption fine‐structure (EXAFS and XANES) measurements. The present study aims to mimic the ... -
Hochtemperatur-Lösungskalorimetrie und Leistungsdifferenzkalorimetrie zur thermodynamischen Charakterisierung von Mineralien
(Univ. Bochum, 2000)Kalorimetrische Untersuchungen sind ein unverzichtbares Instrument bei der Bestimmung der thermodynamischen Eigenschaften von Mineralen, um deren Gleichgewichts- und Reaktionsbeziehungen vorhersagbar zu machen.Im Rahmen ... -
How do secondary iron enrichments form within basaltic eucrites? An experimental approach
(Meteoritics & Planetary Science, 2021-05-02)Some basaltic eucrites and basaltic lithologies in howardites derived from the asteroid 4 Vesta exhibit unusual secondary veinlet textures consisting mostly of fayalitic olivine and Fe‐enrichments within pyroxenes. Recent ... -
How Important is Denitrification in Riparian Zones? Combining End-Member Mixing and Isotope Modeling to Quantify Nitrate Removal from Riparian Groundwater
(Water Resources Research, 2020)Riparian zones are important buffer zones for streams as they are hotspots of nitrate transformation and removal in agricultural catchments. However, mixing of water from different sources and various transformation processes ... -
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 ... -
Hydrochemistry and environmental isotopes (18O, 2H, 3H, 3He/4He) of groundwater and floodwater in the great area of Hurghada, Eastern Desert of Egypt
(Environmental Earth Sciences, 2021-05-28)Porous and fractured aquifers exist in the area of Hurghada, Eastern Desert of Egypt, whose recharge processes through the common flash floods are not identified. Hydrochemical parameters, stable isotopes 18O, ... -
Hydrogen Diffusion in Clinopyroxene at Low Temperatures (195°C–400°C) and Consequences for Subsurface Processes
(Geochemistry, Geophysics, Geosystems, 2022-12-12)Studying diffusion of hydrogen in nominally anhydrous minerals, like clinopyroxene, at low temperatures is a challenging task due to experimental and analytical difficulties. In this study, to overcome these problems we ... -
Hydrothermalsynthesen von PbS-ZnS und FeS-ZnS
(Aachen, Technische Hochschule, Fakultät für Bergbau und Hüttenwesen, 1963)Der Anlaß für die in dieser Arbeit unternommenen hydrothermalsynthetischen Versuche war die auf sulfidischen Bleizinkerzlagerstätten allgemein beobachtete Erscheinung, daß Zinkblende vor Bleiglanz auskristallisiert. Die ... -
Ice Age‐Holocene Similarity of Foraminifera‐Bound Nitrogen Isotope Ratios in the Eastern Equatorial Pacific
(Paleoceanography and Paleoclimatology, 2021-05-19)Bulk sediment δ15N records from the eastern tropical Pacific (ETP) extending back to the last ice age most often show low glacial δ15N, then a deglacial δ15N maximum, followed by a gradual decline to a late Holocene δ15N ... -
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, ... -
Immiscible silicate liquids: K and Fe distribution as a test for chemical equilibrium and insight into the kinetics of magma unmixing
(Contributions to Mineralogy and Petrology, 2021-05-24)Silicate liquid immiscibility leading to formation of mixtures of distinct iron-rich and silica-rich liquids is common in basaltic and andesitic magmas at advanced stages of magma evolution. Experimental modeling of the ... -
Impact Experiment on Gneiss: The Effects of Foliation on Cratering Process
(Journal of Geophysical Research: Solid Earth, 2019)Two impact experiments were carried out on blocks of Maggia gneiss to assess the influence of mechanical target anisotropies on the cratering process. The experiments were done within the framework of Multidisciplinary ...