API src

Found 118 results.

Related terms

Trace element contents for the <2 μm, 2-20 μm and bulk fractions from LGM European loess sequences

Trace element contents in microg/g measured on the <2 microns, 2-20 microns size fractions and bulk samples from LGM European loess sequences. Samples were crushed in an agate mortar and trace element concentrations were measured following Chauvel et al. (2011). Reproducibility for trace element analyses is better than 5% based on repeat measurements, and the accuracy is also better than 5%, based on the analyses of international rock standards (JSD-1, JSD-3 and LKSD-1.

Chemical composition and Sr, Nd, Pb isotope ratios of mafic igneous rocks from the Ordovician Saxothuringian basin east of and within the post-Devonian Müncheberg massif, NE Bavaria, Germany

The sampling area is located east (E-domain) and west (W-domain) of the Münchberg gneiss massif, NE Bavaria. Germany. Major and trace element compositions and Sr, Nd, and Pb isotope composition of a selected subset of Ordovician samples and post- Devonian samples of mafic igneous rocks are documented in the Table 1 'E-domain'. Sr, Nd, and Pb isotope composition of selected mafic igneous rocks from the W-domain of Ordovicician, Silurian, and Devonian age are documented together with the previously analysed Rb-Sr, Sm-Nd, U-Th-Pb concentrations (Höhn et. al., 2018, doi:10.1007/s00531-017-1497-2) in the Table 2 'W-domain'.

Analysis of Mn-deposits from the Alps

In the aftermath of the Triassic?Jurassic extinction event, extant slopes of drowned alpine reef buildups were recolonized in patches by predominantly non-rigid sponges. Just a few localities in the Northern Calcareous Alps display autochthonous communities of these rarely in situ-preserved species and provide an insight into their taphonomy. In a depression of the former Triassic reef surface at Steinplatte (Austria) lyssacinosid sponges formed spicular mats during starved Liassic sedimentation. They settled on detrital soft- or firmgrounds that were successively dominated by spicules of their own death predecessors and infiltrated sediments. Skeletal remains and adjacent micrites were partly fixed by microbially induced carbonate precipitation due to the decay of sponge organic matter. The irregular compaction of the sediment as well as volume reduction during microbialite formation resulted in syndiagenetic stromatactis cavities. Subjacent to the spiculite allochthonous sediments fill up sinkholes and crevices of the rough Triassic relief. In order to define the Lower Liassic paleoenvironment, the sediments and associated ferromanganese crusts were analysed by X-ray fluorescence and ICP-mass spectrometry. The distribution pattern of major and trace elements show usual contents of hydrogeneous Fe/Mn-precipitates. In contrast, the results of rare earth element analyses revealed a negative Cerium anomaly within the crusts and the spiculite at Steinplatte locality. In Lower Liassic sediments of the Northern Calcareous Alps such an anomaly has been proved for the first time. Most likely it is related to higher precipitation rates caused by microbial mats or possibly by a minor influx of hydrothermal fluids. Carbon and oxygen stable isotopes of the same sequence show primary signals of a small negative ?13Ccarb excursion that extends from Hettangian to Lower Sinemurian time.

(Table 1, page 215) Chemical composition Mn deposits from the Middle Jurassic part of the Austrian Kalkalpen

The X-ray diffraction analyzes of two ferromanganese crust samples found at the base of the Klaus red Jurassic limestone beds of the Unterberg formation indicate pyrolusite as the main mineral. The crusts contain also a range of trace elements in concentrations comparable of present day oceanic deposits. The low Fe/Mn ratio found in sample 06-32a is in agreement with the geochemical data from Pacific Ocean manganese nodules and crusts of hydrothermal genesis. However, the simultaneously high contents in cerium and yttrium (rare earth metals) are more likely to suggest a precipitation of the manganese from the free water column (hydrogenetic origin). In addition, there are no identified hydrothermal sources in the vicinity of the hosting limestone beds. Iron-rich manganese nodules have also been found in the Jurrasic limestones beds of the Ruhpolding formation. In these deposits, hematite is the dominant mineral phase. The high Fe/Mn ratio as well the detritic material they contain (quartz, mica) lead to a possible continental margin origin for these nodules.

X-ray Fluorescence (XRF) measurements of floodplain sediments from NEP 1, NEP 2 and NEP 3 from Nördlingen, southern Germany

This data set presents bulk sample-based X-ray Fluorescence (XRF) measurements. For XRF sample preparation freeze-dried sediments from silt-clay overbank deposits of the Eger floodplain in Southern Germany were seaved (2mm) to discard the gravel fraction and large organic matter. Further homogenization was undertaken by grinding the samples with PM 200 planetary ball mill from Retsch. 8 g of sediment sample (<30 µm) homogenized in the ball mill were mixed with 2 g of special wax and homogenized with a shaker. Uniform pellets were formed using a Vaneox press at 20 t for 2 minutes. Elemental analyses were conducted in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer.

Whole-rock chemical analyses from the Heldburg dyke swarm

In the project "Geochemistry and geochronology of the Heldburg dyke swarm, Central European Volcanic Province" we conducted geochemical and geochronological investigations on mafic dykes and former magma chambers of the Heldburg dyke swarm. The latter is part of the Central European Volcanic Province and positioned in the South of Thuringia and the North of Bavaria (Germany). It consists of several hundred mafic NNE-SSW striking dykes with an usual thickness of < 1m and few former magma chambers. All of these have an atypical position within the Central European Volcanic Province located away from Hercynian massifs and major rift axes and were hitherto poorly investigated. In general, 10 different locations of the Heldburg dyke swarm were sampled for whole-rock analyses and 4 different locations were chosen for determining their apatite and zircon ages. The fieldwork was conducted between March 2022 and December 2023. The analytical work was done between June 2022 and April 2024 at the Department of Geodynamics and Geomaterials Research, University of Würzburg (samples preparation, X-ray fluorescence), at the GeoZentrum Nordbayern, University of Erlangen (trace element contents, LA-ICP-MS) and at FIERCE (Frankfurt Isotope & Element Research Center), Goethe University Frankfurt (apatite and zircon ages, LA-ICP-MS). Here, we present the full dataset of 55 whole-rock chemical analyses (X-ray fluorescence, LA-ICP-MS) from ten locations of the Heldburg dyke swarm.

Trace metal distribution for water samples of the cruise AT010

Offshore wind energy is a steadily growing sector contributing to the worldwide energy production. The impact of these offshore constructions on the marine environment, however, remains unclear in many aspects. In fact, little is known about potential emissions from corrosion protection systems such as organic coatings or galvanic anodes composed of Al and Zn alloys, used to protect offshore structures. In order to assess potential chemical emissions from offshore wind farms and their impact on the marine environment water and sediment samples were taken in and around offshore wind farms of the German Bight between 04.04.2022 and 14.04.2022 within the context of the Hereon-BSH project OffChEm II. The water samples were taken in metal-free GO-FLO sampling bottles, filtered over <0.45 µm polycarbonate filters into pre-cleaned LDPE bottles and acidified with nitric acid. The filtrates were then measured for their (trace) metal concentrations with ICP-MS/MS coupled online to a seaFAST preconcentration and matrix removal system.

Metal distribution for sediment samples of the cruise AT010

Offshore wind energy is a steadily growing sector contributing to the worldwide energy production. The impact of these offshore constructions on the marine environment, however, remains unclear in many aspects. In fact, little is known about potential emissions from corrosion protection systems such as organic coatings or galvanic anodes composed of Al and Zn alloys, used to protect offshore structures. In order to assess potential chemical emissions from offshore wind farms and their impact on the marine environment water and sediment samples were taken in and around offshore wind farms of the German Bight between 04.04.2022 and 14.04.2022 within the context of the Hereon-BSH project OffChEm II. The surface sediment samples were taken by a box grab, homogenized, freeze-dried and wet-sieved to gain the <20 µm grain size fraction. The <20 µm grain size fraction was acid digested and measured by ICP-MS/MS for their (trace) metal mass fractions.

Ahr river overbank sediments: XRF elemental composition data set (Mayschoß-Transect, core Ahr2022-1_1, Ahr2022-1_2, Ahr2022-2_1, Ahr2022-2_2)

The elemental composition of samples from four sediment cores from the Mayschoß floodplain (Ahr river) was determined by X-ray fluorescence spectrometry (XRF). In the first step of preparation, large organic matter and pebbles were removed from freeze-dried samples (8 g) by sieving (2 mm). Subsequently, the samples were powdered and homogenised with vibratory Retsch mill MM 200. The uniform pills for the analysis were pressed with a carbon-based binding agent by Vaneox press at 20 t for 2 min. The elemental analysis of 50 elements was conducted in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer. The surface elevation was extracted from Brell et al. (2023).

Beurteilung des Einflusses von degeneriertem Graphit auf das zyklische Werkstoffverhalten von Gusseisen mit Kugelgraphit für dickwandige Komponenten, Teilvorhaben: Einflussfaktoren und metallurgische Verhinderung der Bildung degenerierten Graphits

1 2 3 4 5 … 10 11 12