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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.

Laser ablation inductively coupled mass spectrometry trace elements analyses of Li-rich micas of Pan-African pegmatites in Mozambique

This data report presents the in-situ LA-ICP-MS trace element geochemistry of the micas of the Pan-African rare-element pegmatites of the Alto Ligonha Pegmatite District in northern Mozambique. The pegmatites contain Li-rich micas and primary Li aluminosilicates, such as spodumene. Five Alto Ligonha pegmatites, Naípa, Muiâne, Napepesso West, Nanro, and Natxepo, were investigated to better understand the fractionation of pegmatite melts leading to Li enrichment, utilizing e.g. the trace element chemistry of mica from different parts of these pegmatites. Micas collected from the wall zone, intermediate zone and core zone of the studied pegmatites show high but also highly variable concentrations of the incompatible elements like Li, Rb, Cs, Be, and Ta. Very strong pegmatite-internal fractionation is recorded by the mica chemistry of the Naípa, Muiâne and Nanro pegmatites. In these pegmatites, Li2O in white micas measured with LA-ICP-MS increases from 0.1-1.4 wt.% in the wall zone, to 0.3-1.7 wt.% in the intermediate zone, 1.5-3.8 wt.% in the core zone and up to 5.4 wt.% in the pockets. The data record extreme Li enrichment during the final crystallization stage.

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).

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.

40Ar/39Ar age, whole rock and mineral composition of Cenomanian Serra do Cuó basalts on the Brazilian equatorial margin

This dataset comprises new chemical, isotopic and geochronological analyses for 3 samples from the Cenomanian Serra do Cuó olivine basalts from northeast Brazil. Whole rock major, trace element and Sr-Nd-Pb isotope compositions as well as mineral oxide compositions for pyroxenes, plagioclase, olivine, and Fe-Ti oxides. New analyses on 3 samples are presented in the bulk and in-situ data templates developed by EarthChem. A compilation of all new analyses and previous whole-rock data from Sial (1978) are also provided. Analyses were carried out at the Geoanalítica Core Facility, Isotope Geology Research Center and Geochronological Research Center (CPGeo) at the Instituto de Geociências, University of São Paulo, Brazil. This dataset is supplementary to: Macêdo Filho, A. A., Oliveira, A. L., Klöcking, M., Janasi, V. A., Archanjo, C. J., & Lino, L. M. (2025). Petrology of Cenomanian basalts on the Brazilian equatorial margin: Implications for the tectonomagmatic evolution of the drift phase. Geochemistry, 126248. https://doi.org/10.1016/j.chemer.2025.126248. The data publication includes the following Excel Tables: (1) 2025-002_MacedoFilho_BulkSample_Analyses (DIGIS/EarthChem Template, EarthChem Team, 2022a): Whole rock major, trace element and Sr-Nd-Pb isotope compositions and 40Ar/39Ar age; with additional information on sample collection and analytical methods. (2) 2025-002_MacedoFilho_InSitu_Analyses (DIGIS /EarthChem Template, EarthChem Team, 2022b): Mineral oxide compositions for pyroxene, plagioclase, olivine, and Fe-Ti oxides; with additional information on sample collection and analytical methods. (3) 2025-002_MacedoFilho_suppl-compiled: supplementary data tables from Macêdo Filho et al. (2025). Excel file with the six spreadsheets: Table A1. whole-rock chemistry; Table A2. Feldspar chemistry; Table A3. Pyroxene chemistry; Table A4. Olivine chemistry; Table A5. Titanomagnetite chemistry; Table A6. Ar-Ar Geochronology. Table A1 compiles analyses from Sial (1978) as well as new data. Reference: Sial, A. N. (1978). Major and trace chemistry of the Tertiary basaltic suite of Rio Grande do Norte and Paraíba, northeast Brazil. Jornal de Mineralogia, 7, 119-128.

U-Pb age, whole rock and mineral composition of the Angicos Plutonism (Angicos Batholith and Poço da Oiticica Stock) from northern Borborema Province, NE Brazil

This dataset comprises new chemical, isotopic and geochronological analyses for 14 samples from the Angicos Plutonism (Angicos Batholith and Poço da Oiticica Stock) from northern Borborema Province, NE Brazil. Whole rock major and trace element compositions as well as mineral oxide compositions for feldspars, biotite, and Fe-oxides. New analyses on 14 samples are presented in the bulk and in-situ data templates developed by EarthChem. A compilation of all new analyses and previous whole-rock data from Jardim de Sá (1994) are also provided. Analyses were carried out at the Geoanalítica Core Facility at the Instituto de Geociências, University of São Paulo, Brazil. The data are reported with the EarthChem/ DIGIS data templates (IEDA, 2022).

Integrated Whole-Rock Geochemistry and Isotopic dataset of the Vitória Dike Swarm

This dataset includes new geochemical and isotopic analyses for 10 samples from the Vitória dike swarm in southeastern Brazil. Analytical work was conducted at the Geoanalítica Core Facility of the Instituto de Geociências, University of São Paulo, and at the Geochronology Laboratory of the University of Brasília, both in Brazil.

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

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