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 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 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 – 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 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.