1,168 research outputs found
Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period
No full textLumineszenz-Datierung der Löss-Paläoboden-Sequenz in der Kiesgrube Gaul/Weilbach, Südhessen
No full textA thick Middle and Late Pleistocene loess/palaeosol sequence is exposed at the gravel quarry Gaul located east of Weilbach in the southern foreland of the Taunus Mountains. The loess/palaeosol sequence correlates to the last three glacial cycles. Seven samples were dated by luminescence methods using an elevated temperature IRSL (post-IR IRSL) protocol for polymineral fine-grains to determine the deposition age of the sediment and to set up a more reliable chronological framework for these deposits. The fading corrected IR50 and the pIRIR225 age estimates show a good agreement for almost all samples. The fading corrected IRSL ages range from 23.7 ± 1.6 ka to >350 ka indicating that the oldest loess was deposited during marine isotope stage (MIS) 10 or earlier and that the humic-rich horizon (Weilbacher Humuszone) was developed during the late phase of MIS 7. Loess taken above the fCc horizon most likely accumulated during MIS 6 indicating that the remains of the palaeosol are not belonging to the last interglacial soil. The two uppermost samples indicate that the youngest loess accumulated during MIS 2 (Upper Würmian). Age estimates for the loess-palaeosol sequence of the gravel quarry Gaul/Weilbach could be obtained up to ~350 ka using the pIRIR225 from feldspar. Keywords: loess, luminescence dating, IRSL, fading, Weilbach, chronostratigraphyLumineszenz-Datierung der Löss-Paläoboden-Sequenz in der Kiesgrube Gaul/Weilbach, Südhessen Kurzfassung: Eine mächtige Löss-Paläoboden-Sequenz des Mittel- und Spätpleistozäns ist in der Kiesgrube Gaul östlich von Weilbach im südlichen Taunusvorland aufgeschlossen. Lösse der letzten drei Glazialzyklen, mit zwischengeschalteten Paläoböden, sind aufgeschlossen. Sieben Proben wurden mit der Lumineszenz-Datierungsmethode, basierend auf einem post-IR IRSL Messprotokoll, untersucht, um einen verlässlicheren chronologischen Rahmen für diese Sedimente zu etablieren. Die „fading“ korrigierten IR50 und die pIRIR225 Alter sind für fast alle Proben in guter Übereinstimmung. Die IRSL Alter reichen von 23.7 ± 1.6 ka bis >350 ka und deuten an, dass der älteste Löss während des marinen Isotopenstadiums (MIS) 10 oder früher abgelagert wurde, und dass die Weilbacher Humuszonen sehr wahrscheinlich während einer späten Phase des MIS 7 gebildet wurden. Lösse über dem fCc Horizont wurden sehr wahrscheinlich während des MIS 6 abgelagert, was darauf hindeutet, dass die Reste des Paläobodens nicht mit dem letzten Interglazial korrelieren. Die beiden obersten Proben deuten darauf hin, dass der jüngste Löss während dem letzten Pleniglazial (Oberwürm, MIS 2) abgelagert wurde. Mit dem pIRIR225 Signal konnten Alter bis ~350 ka für die Proben der Löss-Paläoboden-Sequenz in der Kiesgrube Gaul gemessen werden
Grainsize composition of composite sediment core ROD11 from the crater basin of Rodderberg, Germany
No full textGrainsize 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
Palaeoecology and Archaeology of the Kärlich–Seeufer Open-Air Site (Middle Pleistocene) in the Central Rhineland, Germany
No full textThe Kärlich–Seeufer archaeological site in Germany's central Rhineland was excavated between 1980 and 1992. The site provides evidence for hominid activity during a Middle Pleistocene interglaciation known up to now only from the Kärlich clay pit and therefore defined as the Kärlich Interglaciation, which is considered to be post-Cromer IV and pre-Holstein ( sensu stricto ) in age. The site is characterized by Acheulean artifacts, a fauna dominated by Elephas (Palaeoloxodon) antiquus , and a unique and outstanding preservation of wooden and other palaeobotanical remains. Assuming all finds are associated, the site previously was interpreted as an elephant hunting camp with a wooden structure, together with wood and bone implements preserved in situ. Recent analysis of the same features has shown that the site can also be interpreted as a reworked archaeological sample. Hominid occupation occurred in the vicinity of a small lake with prevailing meso-oligotrophic conditions. Expanding boreal forests and fen vegetation characterized the landscape
The Gottingen tree-ring chronologies of peat-preserved oaks and pines from Northwest Germany
No full textTo date, the tree-ring chronology of peat-preserved pines from Northwest Germany (Fig. 1) spans from 6703 BC to 1166 BC, but still contains two gaps. It was dated with the help of the previously constructed bog-oak chronology of Northwest Germany, the older part of which in turn has been dated using the pine chronology (Fig. 2), now covering from 6628 to 6178 BC additional to the previous span of 6069 BC to 931 AD. Compared to the oaks, chronology construction required large numbers of samples of the short-lived pine trees, many of which remained undated or dated relatively only. The dendrochronological process, which at times delivered a multitude of floating chronology fragments, was complemented by a number of radiocarbon dates. Preceding and following the calendar-dated pine chronology, there are radiocarbon dated floating chronologies. This pine record partly dates back to the beginning of the 9th millennium BC and documents environmental conditions during the early Holocene. It also shows the potential of the chronology to be extended further into the past. The Northwest German pine chronology has since been the base for dating i.a. archaeological finds, such as Neolithic wooden bog trackways. Moreover, the peat-preserved pines have proved to be valuable in palaeoenvironmental research, as they grew at sites where they were sensitive to hydrological changes. Particularly the climate-related advances of raised bog are well reflected in the material.German Research Foundation DFG [LE 1805/1-2, FR877/16-1, HA4438/1
Biogenic silica of composite sediment core ROD11 from the crater basin of Rodderberg, Germany
No full textBiogenic 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
No full textMagnetic 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
Bulk geochemistry of composite sediment core ROD11 from the crater basin of Rodderberg, Germany
No full textBulk 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
Love in the First Degree: Manfred, Byron, and Incest
No full textThis is the author accepted manuscript. The final version is freely available from the University of Colorado via the link in this recordNote that the text of the manuscript varies considerably from the final published versionThis essay suggests that Byron’s Manfred contains not an expression of Byron’s guilt about his incest with his half-sister Augusta Leigh, as previous critics have suggested, but rather considerable evidence of his lack of guilt. It argues that the play displays incest and torment, but in fact does not link the two, instead displaying Manfred’s love for Astarte as deeply felt without regrets. The essay then argues that one finds the same combination of deep love and lack of regret in Byron’s remarks about his relationship with his half-sister, as well as in the representations of incest in his other works. It suggests that this acceptance of incest links to Byron’s commitment to rational thinking and personal freedom, and it invites future criticism to explore this connection in more detail
XRF core-scanning data of composite sediment core ROD11 from the crater basin of Rodderberg, Germany
No full textXRF 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
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