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Global compilation of the first occurrence of Gephyrocapsa huxleyi and other Gephyrocapsa species from sediment core samples

The data compilation includes the first occurrence of G. huxleyi and other species of Gephyrocapsa as revealed by Quaternary sediment samples from the world oceans. This new synthesis includes previously published data, all with rigorous relationships of their emergence events with marine isotope stages based on good quality oxygen isotope stratigraphy and/or astronomical tuning from each sediment core.

Loess in Armenia

This project aims to characterize, map, analyze and date recently discovered loess-palaeosol sequences from NE Armenia. These sequences have proved to be especially rewarding because of their thickness (up to 45 m) and the presence of diagnostic tephra layers. The project seeks to derive a standard profile for NE Armenia and thus for the Lesser Caucasus. We will use luminescence technologies to date the loess sections, environmental magnetism to understand soil development, mineralogy to constrain provenance and weathering-potential, and terrestrial Mollusca and biomarkers to evaluate different vegetation formations.

Geochemical and isotopic compositions of minerals and bulk rocks of the Chachimbiro Volcanic Complex (Northern Andes, Ecuador)

This dataset provides geochemical data from from the Quaternary Chachimbiro Volcanic Complex (CVC), situated in the Western Cordillera of Ecuador, Northern Andes (0.468°N, 78.287°W). The CVC is subdivided into 4 eruptive stages (CH1, CH2, CH3, CH4) ranging in age between ~400 and ~4 ka ago (Bellver-Baca et al., 2020). The CH1 stage consists of andesitic flows erupted between 405.7 ± 20.0 and 298.6 ± 32.9 ka with collapse of the pre-existing cone at the end of the effusive period (File #1). The following CH2 stage (121.75 ± 23.2 -36.08 ± 2.8 ka) consists of andesitic to dacitic domes and pyroclastic rocks which also suffered a collapse event as shown by the scar and the uprooted domes in the hillside of the edifice (File #1). The CH3 unit (36.08 ± 0.28 – 22.73 ± 0.12 ka) consists of two main andesitic to dacitic domes (Hugá and Albují: H and A, respectively, in File #1) and effusive rocks. CH4 consists of a volumetrically small rhyodacitic pyroclastic unit which was produced by a lateral blast dated at 5.5-5.8 ky ago. A younger pyroclastic episode (<4.15 ka ago) has been related to the Pucará dome (Comida, 2012), but rocks of this event have not been investigated in the present study. The bulk rock and mineral data are used to reconstruct the plumbing system beneath the CVC during its ~400 ka long lifetime. Since the temporal geochemical evolution of CVC bulk rocks towards higher values of adakite-like indices (e.g., Sr/Y, La/Yb) bears strong similarities to that of magmatic systems associated with supergiant porphyry copper deposits, these data may serve to better understand how adakite-like signatures are acquired in fertile arc magmatic systems with metallogenic implications. Files included are: • 2024-018_Chiaradia-et-al_Table-1_Sample-overview: sample overview table with coordinates of and type of analyses carried out on each sample (Table #1) • 2024-018_Chiaradia-et-al_File_1_map: a geological map with location of investigated samples (File #1) • 2024-018_Chiaradia-et-al_File_2_WholeRocks: geochemical and radiogenic isotope data on bulk rocks (File #2). • 2024-018_Chiaradia-et-al_File_3_Pyroxene: contains microprobe and LA-ICP-MS major and trace element analyses of clino- and orthopyroxenes from the CVC and P-T conditions retrieved from clinopyroxene compositions (File #3) • 2024-018_Chiaradia-et-al_File_4_Amphibole: contains microprobe and LA-ICP-MS major and trace element analyses of amphiboles from the CVC and P-T-H2Omelt, fO2 conditions retrieved from amphibole compositions (File #4). • 2024-018_Chiaradia-et-al_File_5_Plagioclase: contains microprobe and LA-ICP-MS major and trace element analyses of plagioclases from the CVC (File #5). • 2024-018_Chiaradia-et-al_File_6_Equilibrium tests: reports the calculations to retrieve pressure and temperature data from clinopyroxene-melt equilibrium and clinopyroxene-only composition (File #6). • 2024-018_Chiaradia-et-al_File_7_CPX_Thermo_Barometry: reports the calculations to obtain P-T conditions from clinopyroxene-orthopyroxene equilibria in the same thin section (File #7). • 2024-018_Chiaradia-et-al_File_8_Cpx_Opx_Thermo_Barometry: reports the equilibrium tests between minerals (clinopyroxene, orthopyroxene, amphibole) and host rock compositions and the P-T values retrieved by clinopyroxene and amphibole analyses that passed the test (File #8). Associated RStudio Scripts are available as https://doi.org/10.5880/fidgeo.2025.010 (Chiarada, 2025).

Multi-proxy analysis of two loess-paleosol sequences in southern Germany

Two loess-paleosol sequences from the Heilbronn Basin in southwestern Germany, Frankenbach and Talheim, have been investigated to gain information about environmental conditions during the last interglacial-glacial cycle. Since paleoenvironmental research on terrestrial archives is crucial for understanding past climatic and environmental conditions, the profiles were studied using a multi-proxy approach. Applied methods include the analyses of grain-size distribution, element concentrations, color data, and rock magnetism. The data reveal that the two profiles show large variations in conservation due to their different geomorphologic positions. Moreover, the results imply a subarctic climate with stable conditions during the Middle Pleniglacial (MIS 3) in-situ soil formation phase. At the same time, the Lower Pleniglacial (MIS 4) was characterized by erosion and reworking of Eemian and Early Glacial (MIS 5) material but also by the accumulation of aeolian material during the late Lower Pleniglacial (MIS 4) in Frankenbach. The results further suggest that the Rhine River floodplain has been a major source for the accumulated material in the two profiles, which indicates westerly wind directions during the time of accumulation. The low GSI and U-Ratio of Upper Pleniglacial (MIS 2) sediments, supported by the overall high content of fine material, imply a larger distance to the source area. We give an overview of loess in the Heilbronn Basin and place it in a wider context of loess in Western Europe.

Grain size anaylsis from the Talheim loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

Grain size anaylsis from the Frankenbach loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

Rock magnetic data of the Talheim loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

Geochemical anaylsis from the Talheim loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

Geochemical anaylsis from the Frankenbach loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

Rock magnetic data of the Frankenbach loess-paleosol sequence in the Heilbronn Basin, southwestern Germany

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