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Geochemical signature of last glacial maximum European loess samples

In a previous analysis of bulk sediment from Last Glacial Maximum loess deposits over Europe, a local to regional origin of the deposited material has been demonstrated (Rousseau et al., 2014). In a refined study, the same European sequences have been analyzed studying the trace elements and the strontium and lead isotopic ratios from different grain-size fractions: <2 micron, 2-20 micron and bulk. The later was reanalyzed to compare with the previous study. First the new bulk values are similar to the previously published ones. Furthermore, the results show that the <2 micron fraction is different than the 2-20 micron or bulk ones when comparing the trace element. Second, the 87Sr/86Sr vs 208Pb/204Pb diagram shows that the sequences analyzed keep their regional to local signature, mainly along the 87Sr/86Sr axis for the 2-20 micron and bulk samples. On the contrary, the <2 micron samples are all grouped in a well identified cluster clearly indicating a different source and even a different transport. The comparison of the results of the geochemical analysis with climate modeling of dust transport at LGM supports this interpretation. The datasets correspond to i) the code and geographical coordinates, ii) the trace element contents for the <2 micron, 2-20 micron and bulk fractions, iii) the Sr-Pb isotopic ratios for the <2 micron, 2-20 micron and bulk fractions, and iv) the grain size composition of the studied LGM European loess samples.

Water and sediment analysis from column experiments

This data set contains data from water analyses from column experiments. The water analyses included cations (sodium, potassium, calcium, magnesium, iron and manganese), anions (nitrate, chloride, sulphate, bromide and phosphate) and selected trace elements (arsenic, cobalt, nickel, vanadium and zinc). The column experiments were conducted with two different types of unconsolidated sandy sediments from aquifers in Denmark (Quaternary) and Germany (Cretaceous). In both sediments, the nitrate degradation capacity was almost exhausted. To induce denitrification, 5 mmol ethanol was added to the column experiments. This also caused a decrease in the concentration of trace elements in the water. A sequential extraction procedure was performed to determine the trace element sinks. The data set therefore also contains contents of selected elements (equal to water analyses) from the sequential extraction procedure of the sediment before and after the column tests. The results observed in the laboratory were additionally modeled with Phreeqc. The Phreeqc input data complete the data set.

Foraminiferal geochemistry and assemblage data, and pore water oxygen data of IODP Site 347-M0059

The dataset includes foraminiferal geochemistry and assemblage data, and pore water oxygen isotopes. The samples were collected during IODP Expedition 347 from Site M0059, located in the southern section of the Little Belt in the Baltic Sea. We have measured trace element concentrations (by LA-ICP-MS), oxygen and carbon isotopes of foraminiferal calcite, and fauna assemblage, for reconstruction of past environmental conditions over the past ~7.5 thousand years. We have also measured pore water oxygen isotopes from the same site. In the dataset we also present the trace element concentrations of foraminiferal calcite from IODP347 Site M0059 measured by solution-based ICP-OES. In addition, we include the measurement of water column salinity and oxygen isotopes data from cruise MSM 50 between the Skagerrak and the southern Baltic Sea.

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.

Grain size composition of LGM European loess samples

Grain size composition of loess samples from LGM European loess sequences. Loess samples of about 200 g were prepared to extract the grain size fractions studied. Grain size separations were performed on at least 10 g of dry sample. First, the entire sample was sieved with demineralized water on 63 microns and 20 microns sieves. The rejects were collected, dried and weighed. The clay fraction was obtained by decanting the fraction below 20 microns. The rest of the sample was mixed and left to settle for 1 hour. This procedure is repeated until a transparent supernatant is obtained. The two fractions thus obtained are dried and weighed. The size of the different fractions was then checked by laser granulometry.

Sr-Pb isotopic ratios for the <2 μm, 2-20 μm and bulk fractions from LGM European loess sequences

Sr-Pb isotopic ratios for the <2 microns, 2-20 microns size fractions and bulk samples from LGM European loess sequences. Samples were crushed in an agate mortar and Sr and Pb isotopes were measured following Chauvel et al. (2011). Lead and strontium were analyzed after dissolution of the powder and without leaching procedure. Blanks run in parallel with the samples during the course of this work were less than 80 pg of Pb and 250 pg of Sr for the entire chemical separation procedure. These amounts are negligible relative to the amount of Pb and Sr present in the beakers after isolation of pure Pb and Sr (typically, 600 ng of Pb and 4 microg of Sr).

Global mantle clinopyroxene data (major and trace elements)

Compilation of global major and trace element compositional data for clinopyroxenes from mantle xenoliths from 972 locations worldwide, originally downloaded from the GEOROC database (https://georoc.eu/; accessed 14 July 2020). Each location includes multiple samples and analyses. To exclude unreliable samples, we used only clinopyroxenes with 40–60 wt.% SiO2, <40 wt.% MgO, <30 wt.% FeOT, <26 wt.% CaO, and oxide totals of 98.5–101.5 wt.%. Elements missing from >60% of the entire dataset were not considered. The dataset contains 21,605 observations (rows) corresponding to clinopyroxene major element analyses (SiO2, TiO2, Al2O3, Cr2O3, FeOT, CaO, MgO, MnO, and Na2O), and 2,967 rows of trace element analyses (including Sc, Ti, V, Cr, Ni, Rb, Sr, Y, Zr, Nb, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Pb, Th, and U). Database as published in Qin et al. (2022).

Stable oxygen isotope ratios of pore water from IODP Site 347-M0059

Solution based trace element concentration of IODP Site 347-M0059

Concentrations of selected elements and organochlorine pesticides in layers of dated sediment cores of ten lakes in northeastern Germany

Lake sediment chronologies of ten lakes in northeastern Germany (Arendsee [AS], Carwitzer See [CR], Feldberger Haussee [FH], Breiter Luzin [BL], Schmaler Luzin [SL], Oberuckersee [OR], Scharmützelsee [PL], Stechlinsee [ST], Tiefwarensee [TF], Großer Wummsee [WM]) were created to reconstruct anthropogenic activity over the past 100 years starting from 2015 as the most present date. Collection of samples took place between 2015-07-10 and 2015-09-04 for all but one lake which was re-sampled in December 2016 (ST). Cores of lake sediments were collected using a gravity corer (90 mm diameter; UWITEC, Mondsee, Austria). Minimum length of the cores was 1 m. Cores were sliced immediately at the shore of each lake into 5 mm (lakes FH and BL) or 10 mm samples (all other lakes). Sliced cores were stored at 4 °C until arrival at the IGB laboratory at Lake Stechlin. There, they were weighed and then frozen at -20 °C for storage until further processing. Loss of ignition was determined using an electric muffle furnace (SNOL 8,2/1100, Utena, Lithuania). Dating of each sliced core horizon was performed by direct gamma assay of isotopes 210Pb and 137Cs of a freeze-dried subsample (1 g). Depending on the lake, a time span starting with the sampling year (i.e. 2015/2016) and reaching back to at least the 1950s and at most to pre-1900s was covered. Concentrations of elements (aluminium, arsenic, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, molybdenum, sodium, nickel, phosphorus, lead, sulphur, zinc) were determined with microwave-assisted aqua-regia (MAE-AR) extraction in conjunction with inductively coupled plasma-optical emission spectrometry (ICP-OES). Concentrations of organic pesticides DDX (2,4'- and 4,4'- congeners of each dichlorodiphenyltrichloroethane [DDT], dichlorodiphenyldichloroethane [DDD] and dichlorodiphenyldichloroethylene [DDE]), hexachlorobenzene (HCB), HCHs (α-, β-, γ-, δ-hexachlorocyclohexane [HCH]) and trifluralin were extracted applying miniaturized solid-liquid extraction (MISOLEX; Simon et al. 2021, doi:10.1007/s11368-021-03080-0). Extracts were measured with solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS).

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