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XRF core-scanning data of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

XRF core-scanning data characterizes the sediment composition geochemically and supports palaeoclimatic reconstruction of glacial/interglacial cycles for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany. A 72.8 m long sediment record was recovered by means of wire-line drilling with 3 m long liners from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. The composite record ROD11 was subjected to XRF core scanning with a spatial resolution of 2 mm using an ITRAX XRF core scanner, Cox Analytics with a Molybdenum X-ray tube (Croudace et al., 2019; Croudace and Rothwell, 2015). The measurements were conducted with a fixed setting of 30 kV, 40 mA, and an exposure time of 5 s. The software Q-spec (Cox Analytics) was employed for processing of the scanner output and calculation of qualitative elemental measurements in counts. Principal component analysis was then employed to reduce the data dimension and identify latent environmental control factors for the reliable set of elemental data in the normalized (clr-transformed) and standardized XRF dataset (Bertrand et al., 2024). Valued by multiple dating techniques for the past 430 ka, this terrestrial record provides an environmental reconstruction since the Middle Pleistocene.

Bulk geochemistry of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

Bulk geochemistry characterizes sediment composition and supports palaeoclimatic reconstruction of glacial/interglacial cycles for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany. A sediment record measuring 72.8 m in length was retrieved by employing wire-line drilling techniques, utilising 3 m-long liners, from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. The composite record ROD11 was subjected to continuous analysis for bulk geochemistry (total carbon, total nitrogen, total sulphur) with 10 cm spatial resolution employing a CNS analyser (EuroEA, Eurovector). Additionally, the analysis of total organic carbon was carried out with the same setup but after the destruction of carbonates with 3% and 20% sulphuric acid. The difference between total carbon and total organic carbon yields total inorganic carbon, a proxy parameter for carbonates. The calculation of organic matter was performed by multiplication of total organic carbon with a value of 2.13, in accordance with the methodology proposed by Dean (1974). The calculation of carbonaceous matter was accomplished by multiplying total inorganic carbon values with 8.33, in order to account for the stoichiometric mass change from C to CaCO3. Minerogenic matter was determined as the difference between 100 and the sum of organic matter and carbonaceous matter. These parameters enhance the palaeoclimatic interpretation for the past 430 ka. Valued by multiple dating techniques, this terrestrial record provides an environmental reconstruction since the Middle Pleistocene.

Biogenic silica of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

Biogenic silica data characterize lacustrine sediments and support the palaeoclimatic interpretation of interglacials for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany A 72.8 m long sediment record was recovered by means of wire-line drilling with 3 m long liners from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. The composite record ROD11 was analysed for the presence of biogenic silica, with a 20 cm spatial resolution for interglacial periods and a 100 cm spatial resolution for glacial periods. The investigations were conducted using automated leaching in a continuous flow system (Müller and Schneider, 1993). The extraction of biogenic silica was performed with 1 M NaOH solution at a temperature of 85 °C. The presence of dissolved biogenic silica was detected through spectrophotometric analysis. This parameter serves as a proxy for the presence of diatoms in the sediment record and indicates the depositional conditions in a lake and its trophic state. This proxy parameter enhances the interpretation of organic matter, which is not only of lacustrine origin but can also be contributed by in wash of terrestrial plant remains, and the palaeoclimatic interpretation over the past 430 ka. The terrestrial record from Rodderberg is of significant value, as it can be dated using multiple techniques and provides a reconstruction of the environment since the Middle Pleistocene.

Magnetic susceptibility of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

Magnetic susceptibility – a proxy parameter for core correlation and reconstruction of glacial/interglacial cycles for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany. A 72.8 m long sediment record was recovered by means of wire-line drilling with 3 m long liners from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. The two drill holes (ROD11-2 and ROD11-3) were merged to establish a composite record (ROD11) based on macroscopic sediment description and were fine-tuned by magnetic susceptibility data. Magnetic susceptibility was continuously logged with 1 cm spatial resolution with a Bartington loop-sensor (MS2C) on a GEOTEK multi-sensor core-logger. Furthermore, this parameter facilitates the differentiation between glacial and interglacial sediments, thereby supporting the palaeoclimatic interpretation based on geochemical data spanning the past 430 ka. The combined evidence suggests a depositional evolution from a deep crater lake via a shallow lake or desiccating wetland followed by deposition of loess and pedogenesis. This terrestrial record, evaluated through multiple dating techniques, offers a comprehensive environmental reconstruction since the Middle Pleistocene.

Grainsize composition of composite sediment core ROD11 from the crater basin of Rodderberg, Germany

Grainsize data supports palaeoclimatic reconstruction of glacial/interglacial cycles for the Middle Pleistocene sediment record from the crater basin of Rodderberg, Germany. A sediment record measuring 72.8 m in length was retrieved by employing wire-line drilling techniques, utilising 3 m-long liners, from the silted-up crater basin of Rodderberg (East Eifel Volcanic Field) in the vicinity of the city of Bonn, Germany. For the purpose of grainsize analysis, the composite record ROD11 was systematically subsampled at a spatial resolution of 2 cm and examined through a laser diffraction particle size analyser (Beckman Coulter LS 13320). The resulting sedimentological data characterise glacials as silt-dominated (aeolian sediments: loess), interglacials as sand-dominated (runoff-related deposits from the step crater walls) and clay dominance for the Holocene soil. The terrestrial sediment record has been evaluated through multiple dating techniques and it provides a comprehensive environmental reconstruction since the Middle Pleistocene, thus providing valuable insights into the region's climate history.

GEMAS – Geochemische Kartierung der Acker- und Grünlandböden Europas, Parameter und Indizes, Magnetische Suszeptibilität

GEMAS (Geochemical Mapping of Agricultural and Grazing Land Soil in Europe) ist ein Kooperationsprojekt zwischen der Expertengruppe „Geochemie“ der europäischen geologischen Dienste (EuroGeoSurveys) und Eurometeaux (Verbund der europäischen Metallindustrie). Insgesamt waren an der Durchführung des Projektes weltweit über 60 internationale Organisationen und Institutionen beteiligt. In den Jahren 2008 und 2009 wurden in 33 europäischen Ländern auf einer Fläche von 5 600 000 km² insgesamt 2219 Ackerproben (Ackerlandböden, 0 – 20 cm, Ap-Proben) und 2127 Grünlandproben (Weidelandböden, 0 – 10 cm, Gr-Proben) entnommen. Neben den chemischen Elementgehalten wurden in den Proben auch Bodeneigenschaften und -parameter wie der pH-Wert, die Korngrößenverteilung, die effektive Kationenaustauschkapazität (CEC), MIR-Spektren und die magnetische Suszeptibilität untersucht sowie einige Koeffizienten berechnet. Die Downloaddateien zeigen die flächenhafte Verteilung der magnetischen Suszeptibilität in Form von farbigen Isoflächenkarten.

New and compiled palaeomagnetic data from western Ross Sea (Antarctica) spanning the last ca. 10 ka

This dataset includes both original and previously published paleomagnetic data. The new data refer to a marine sediment sequence (ANTA02-AV43 core) collected in the in Wood Bay, located along the coast of Victoria Land, within the western Ross Sea (Antarctica) and spanning the last ca. 10 ka. The formerly published paleomagnetic data from coeval sediment cores refer to the from the RS15‐GC57 core of Truax et al. (2025) collected in the adjacent Robertson Bay, and from the PC18 and PC19 cores of Macrì et al. (2005), recovered from the continental rise of the Wilkes Land basin offshore the coast of East Antarctica. The data from these two latter cores were relocated to the location of the ANTA02-AV43 core with the Noel and Batt (1990) method. The estimated age of the formerly published dataset has been re-evaluated after correlation of paleomagnetic trends with the ANTA02-AV43 core and prediction of geomagnetic variation at the ANTA02-AV43 site according to the CALS10k.2 model of Constable et al. (2016). We then combined the new ANTA02-AV43 dataset with existing Holocene records from sediment cores of comparable resolution (PC18 and PC19) to develop the paleomagnetic “HOLOANTA” stack. This composite record averages paleomagnetic data over the last 10,000 years in 200-year intervals. It includes relative paleointensity (RPI) as well as paleomagnetic inclination and declination data, providing a robust regional Holocene RPI curve alongside directional secular variation (PSV) trends.

Magnetic susceptibility record of the Pod Barrandovem section (Praha Formation)

The Early Devonian geological time scale (base of the Devonian at 418.8 ±2.9Myr, Becker et al. (2012; doi:10.1016/B978-0-444-59425-9.00022-6) suffers from poor age control, with associated large uncertainties between 2.5 and 4.2 Myr on the stage boundaries. Identifying orbital cycles from sedimentary successions can serve as a very powerful chronometer to test and, where appropriate, improve age models. Here, we focus on the Lochkovian and Pragian, the two lowermost Devonian stages. High-resolution magnetic susceptibility (χin- 5 to 10 cm sampling interval) record are gathered from one main limestone section, the Pod Barrandovem (174 m; Praha Formation) in the Czech Republic. This record is used with two other records (Pozare and Branzovy) to provide a cyclostratigraphic time scale and to provide time estimates for the Lochkovian and Pragian. Magnetic susceptibility (χin) measurements have been carried out in different laboratories. Using a KLY-2 at the Czech Academy of Sciences and a MFK-1 at Utrecht University, both are Kappabridge device, manufactured by AGICO (Brno, Czech Republic).

Magnetochronostratigraphic data from marine sediments off Patagonia, SE Pacific – cores from expedition MR16-09 Leg 2, Japanese RV Mirai, 2017

Sediment cores PC02, PC03, and PC04 were recovered during the ship expedition MR16-09 Leg 2 of Japanese RV Mirai in 2017 (Murata et al., 2017) using piston corers. For paleo- and rock magnetic analyses clear plastic boxes with a volume of 7 cm3 were pressed into the split halves of the generally 1 m long sections of the sediment cores. X-ray fluoresence (XRF) scans were performed with an Itrax XRF Corescanner (Cox Analytical systems) at Kochi Core Center, Japan (Hagemann et al. 2024). The downcore resolution was set to 5 mm, and the scans were performed with a Mo X-ray tube at 30 kV and 55 mA for a measurement time of 15 s. The Itrax X-ray beam was set to 0.2 mm × 20 mm. Measurements of low-field magnetic susceptibility (klf same as: k-bulk) and its anisotropy (AMS) were performed with an AGICO MFK1-A susceptibility meter. The principal AMS axes Kmax, Kint, and Kmin, the three axes of the anisotropy ellipsoid, were used to calculate the degree of anisotropy, as well as the shape factor of anisotropy. The frequency dependency of magnetic susceptibility was determined with an automated MAGNON Variable Field Susceptibility Meter (VFSM) by measuring magnetic susceptibility at different frequencies with logarithmically equidistant steps at a field amplitude of 250 µT. Susceptibilities of core PC02 samples were measured at 7 frequencies F from 375 Hz to 4775 Hz. Samples from cores PC03 and PC04 were measured at 5 frequencies from 475 to 4775 Hz. The frequency dependency Dk/Dlog(F) then was determined by linear regression of susceptibility k versus the decadal logarithm of frequency F. Values are given as decay rate in percent over one frequency decade (% / decade (F)) relative to the measurement at the lowest frequency. Thus, values obtained are negative. Measurements of the natural remanent magnetization (NRM) and of the anhysteretic remanent magnetization (ARM) were performed with a 2G 755 SRM long-core cryogenic magnetometer. ARMs were produced with a 2G660 single-axis alternating field (AF) demagnetizer using 100 mT alternating field and 50 µT static field. NRMs and ARMs both were stepwise demagnetized with the in-line 3-axes AF demagnetizer of the cryogenic magnetometer. AF steps for NRM: 0, 5, 10, 15, 20, 30, 40, 50, 65, 80, 100 mT. AF steps for ARM: 0, 10, 20, 30, 40, 50, 65, 80 mT. Iso-thermal remanent magnetizations (IRM) were imparted with a 2G 660 pulse magnetizer using 1500 mT for producing a saturation magnetization (SIRM) and -200 mT for remagnetization of the low-coercive fraction. Measurements were performed with a Molyneux spinner magnetometer. Data records were turned into time series by applying the age model for PC03 (Hagemann et al., 2024), correlating PC02 to PC03, and correlating PC04 to PC03 (back to 140 ka) and further using the PISO1500 paleointensity stack (Channell et al., 2009), paleomagnetic data from the Black Sea (Liu et al., 2020, Nowaczyk et al., 2021), and paleoclimatic data from Antarctica (Jouzel et al., 2007; Bazin et al., 2013) for reference for older core sections.

Magnetochronostratigraphic data from sediments in the Drake Passage – cores from expedition PS97, German RV Polarstern, 2016

Sediment cores were recovered during the ship expedition of German RV Polarstern in 2016 (PS97) using piston corers. For paleo- and rock magnetic analyses clear plastic boxes of 20×20×15 mm were pressed into the split halves of the generally 1 m long sections of the sediment cores. In order to determine the direction of the characteristic remanent magnetization (ChRM), demagnetization results of the NRM were subjected to principal component analysis (PCA) according to Kirschvink (1980). The PCA also provided the maximum angular deviation (MAD) as a measure of the precision of the determined ChRM direction. ChRM declinations obtained by PCA were rotated around a vertical axis until the declinations of all samples falling into a circular window of 35° around the direction expected from a geocentric axial dipole (-72.9°) yielded a mean of 0°. ChRM data from core PS97-085-1 (-85-3) were tentatively tilted by +17° (-7°) around the EW axis in order to parallel the maximum in the inclination distribution with the inclination of a geocentric axial dipole field. The anhysteretic susceptibility K(ARM) is defined as the ARM intensity normalised by the static field used for producing the ARM. The anhysteretic susceptibility normalised by the low field bulk susceptibility K(ARM)/klf then is a magnetic grain size proxy with low (high) ratios indicating relatively large (small) magnetite particles. In order to discriminate samples being dominated by low-coercive minerals (magnetite, Fe3O4 and greigite, Fe3S4) from samples being dominated by high-coercive minerals (mostly hematite, Fe2O3), the S-ratio was calculated using S=0.5×(1-[IRM(-200 mT)/SIRM(1500 mT)]). S-ratios range from 0 to 1, with: dominance of magnetite/greigite: 0<<S≤1, and dominance of hematite: 0≤S<<1. As another grain size proxy the ARM intensity was normalised by the SIRM: (1000×ARM/SIRM) with low (high) ratios indicating relatively large (small) magnetite particles. The factor of 1000 is introduced in order to avoid small numbers. Relative paleointensity variations were estimated by three different proxies: slope of NRM vs. ARM of common demagnetization steps (slope(NRM/ARM)), NRM intensity demagnetized with 30 mT normalized with bulk susceptibility klf (pjk(30mT)), and NRM intensity demagnetized with 30 mT normalized with saturation magnetization SIRM (pjs(30mT)). Data records were turned into time series by correlation to dated reference records from Antarctica (Wu et al., 2021) and the Black Sea (Liu et al., 2021).

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