Browsing Geochemie, Mineralogie, Petrologie by Title
Now showing items 1-20 of 395
-
10Be/9Be Ratios Reveal Marine Authigenic Clay Formation
Bernhardt, A.; Oelze, M.; Bouchez, J.;
; Mohtadi, M.; Christl, M.; Wittmann, H. (Geophysical Research Letters, 2020-02-10)
As reverse weathering has been shown to impact long‐term changes in atmospheric CO2 levels, it is crucial to develop quantitative tools to reconstruct marine authigenic clay formation. We explored the potential of the ... -
A discussion on `Domain formation and phase transitions in the wurtzite‐based heterovalent ternaries: a Landau theory analysis'
Quayle, Paul C.; (Acta Crystallographica Section A, 2021-03-23)
Heterovalent ternary nitrides are considered one of the promising classes of materials for photovoltaics, combining attractive physical properties with low toxicity and element abundance. One of the front‐runner systems ... -
A history of violence: magma incubation, timing and tephra distribution of the Los Chocoyos supereruption (Atitlán Caldera, Guatemala)
; Schindlbeck‐Belo, Julie C.; ; ; ; ; Pérez, Wendy; Harvey, Janet C.; Wang, Kuo‐Lung; Lee, Hao‐Yang (Journal of Quaternary Science, 2021-01-11)
The climactic Los Chocoyos (LCY) eruption from Atitlán caldera (Guatemala) is a key chronostratigraphic marker for the Quaternary period given the extensive distribution of its deposits that reached both the Pacific and ... -
A new concept for temporal gating of synchrotron X‐ray pulses
(Journal of Synchrotron Radiation, 2021-02-05)A new concept for temporal gating of synchrotron X‐ray pulses based on laser‐induced thermal transient gratings is presented. First experimental tests of the concept yield a diffraction efficiency of 0.18%; however, the ... -
A new hydrate of magnesium carbonate, MgCO3·6H2O
(Acta Crystallographica Section C, 2020)During investigations of the formation of hydrated magnesium carbonates, a sample of the previously unknown magnesium carbonate hexahydrate (MgCO3·6H2O) was synthesized in an aqueous solution at 273.15 K. The crystal ... -
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 ... -
A novel experimental approach for nanostructure analysis: simultaneous small-angle X-ray and neutron scattering
(Journal of Applied Crystallography, 2020)Exploiting small-angle X-ray and neutron scattering (SAXS/SANS) on the same sample volume at the same time provides complementary nanoscale structural information in two different contrast situations. Unlike an independent ... -
A Triad Photoanode for Visible Light‐Driven Water Oxidation via Immobilization of Molecular Polyoxometalate on Polymeric Carbon Nitride
; ; ; ; ; ; ; ; (Advanced Sustainable Systems, 2022-03-08)
Due to their availability, low cost, nontoxicity, and tunability, polymeric carbon nitrides (CNx) represent one of the most attractive materials classes for the development of fully sustainable photo(electro)catalytic ... -
Advances in understanding calcite varve formation: new insights from a dual lake monitoring approach in the southern Baltic lowlands
; Dräger, Nadine; ; ; Pinkerneil, Sylvia; ; Lindemann, Christin; ; Brademann, Brian; Kaszubski, Michał; ; ; ; ; Brauer, Achim (Boreas, 2021-02-09)
We revise the conceptual model of calcite varves and present, for the first time, a dual lake monitoring study in two alkaline lakes providing new insights into the seasonal sedimentation processes forming these varves. ... -
Airborne and ground level flask sampling for regional carbon budgets - the potential of multiple tracer and isotope analyses ; development of a new "Investigation Strategy" and of an improved "Sampling System"
(Univ. Hamburg, 2005)Aim of the study was to test the capability of multiple trace gas analyses for the assessment of regional carbon budgets. Therefore, air samples were taken by airborne and ground level activities during several field ... -
Amplified Arctic Surface Warming and Sea Ice Loss Due to Phytoplankton and Colored Dissolved Material
; Losa, Svetlana N.; ; ; (Geophysical Research Letters, 2020-11-02)
Optically active water constituents attenuate solar radiation and hence affect the vertical distribution of energy in the upper ocean. To understand their implications, we operate an ocean biogeochemical model coupled to ... -
An unusual compound object in Yamato 793408 (H3.2-an): The missing link between compound chondrules and macrochondrules?
; ; ; Gurenko, Andrey; (Meteoritics & Planetary Science, 2020)
We found a large (~2 mm) compound object in the primitive Yamato 793408 (H3.2-an) chondrite. It consists mostly of microcrystalline material, similar to chondrule mesostasis, that hosts an intact barred olivine (BO) ... -
Analyse von Butylzinnverbindungen in Sedimenten mittels GC-AED
(Univ. Hamburg, 2007)Organotin compounds are variously used industrial chemicals. One of the most toxicological relevant compounds is tributyltin (TBT). TBT has been used as an effective component in antifouling paints for decades. Thus, it ... -
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 ... -
Anomalous SAXS at P12 beamline EMBL Hamburg: instrumentation and applications
(Journal of Synchrotron Radiation, 2021-05-02)Small‐angle X‐ray scattering (SAXS) is an established method for studying nanostructured systems and in particular biological macromolecules in solution. To obtain element‐specific information about the sample, anomalous ... -
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 ... -
Arsenic release from a natural rock under near-natural oxidizing conditions
; Chen-Braucher, D.; Schlothauer, Th. (Engineering in life sciences, 2008)
The solubilization of arsenic (As) from an ore material (native Arsenic [As, trig.] with Lollingite [FeAs2, rh.]) was characterized in leaching tests lasting for ≤ 99 days. The experiments were performed with materials of ... -
Assessing the Potential for Mobilization of Old Soil Carbon After Permafrost Thaw: A Synthesis of 14C Measurements From the Northern Permafrost Region
Estop‐Aragonés, Cristian;; ; ; ; ; Egan, Jocelyn E.; ; Garnett, Mark H.; Hartley, Iain P.; ; ; Natali, Susan M.; O'Donnell, Jonathan A.; ; Tanentzap, Andrew J.; ; ; Turetsky, Merritt; Anthony, Katey Walter (Global Biogeochemical Cycles, 2020-09-14)
The magnitude of future emissions of greenhouse gases from the northern permafrost region depends crucially on the mineralization of soil organic carbon (SOC) that has accumulated over millennia in these perennially frozen ... -
Assessing the robustness of carbonate‐associated sulfate during hydrothermal dolomitization of the Latemar platform, Italy
; ; ; (Terra Nova, 2021-09-12)
Carbonate‐associated sulfate (CAS) is an important proxy for reconstructing marine sulfur cycling throughout Earth's history. In order to assess the impact of carbonate neomorphism on δ34SCAS data, a mineralogical‐spatial ... -
Assessing Volcanic Controls on Miocene Climate Change
; ; ; (Geophysical Research Letters, 2022-01-18)
The Miocene period saw substantially warmer Earth surface temperatures than today, particularly during a period of global warming called the Mid Miocene Climatic Optimum (MMCO; ∼17–15 Ma). However, the long‐term drivers ...
