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| Titel |
In situ produced 10Be depth profiles and luminescence data tracing climatic and tectonic control on terrace formation, Danube River, Central Europe, Hungary |
| VerfasserIn |
Zsófia Ruszkiczay-Rüdiger, Régis Braucher, Ágnes Novothny, Gábor Csillag, László Fodor, Gábor Molnár, Balázs Madarász, Aster Team |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250107266
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| Publikation (Nr.) |
 EGU/EGU2015-15847.pdf |
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| Zusammenfassung |
| The terrace sequence of the Hungarian part of the Danube valley preserves a record of
varying tectonic uplift rates along the river course and throughout several climate
stages. To establish the chronology of formation of these terraces, two different
dating methods on alluvial terraces were used: 1) in situ produced cosmogenic
10Be, which yield the time of abandonment of the terrace and 2) luminescence
dating, which provides burial ages of the sediment. In situ produced cosmogenic
10Be samples originated from vertical depth profiles to enable the determination of
both the exposure time and the denudation rate at each locality. We used Monte
Carlo approach to model the denudation rate-corrected exposure ages. Post-IR
IRSL measurements were carried out on K-feldspar samples to obtain the ages of
sedimentation.
The highest and oldest terrace remnants (tIV-VI) yield a minimum 10Be exposure age of
800 ka close to MIS 22, the onset of major continental glaciations of Quaternary age,
suggesting climatic signal of the abandonment of the uppermost terrace levels. For the lower
terraces it was possible to reveal close correlation with MIS stages using IRSL ages. The new
chronology enables the distinction of tIIb (60-110 ka; MIS 4-5d) and tIIIa (130-190 ka;
MIS 6) in the study area. Surface denudation rates were well constrained by the
cosmogenic 10Be depth profiles between 5.9 m/Ma and 10.0 m/Ma for all terraces.
Maximum incision rates of the Danube were calculated for middle and late Pleistocene
times. These rates were increasing from west to east, toward the more elevated
Transdanubian Range from 0.05 mm/a to 0.12 mm/a. Incision rates derived from the age of
the low terraces (0.13 mm/a) may suggest a slight acceleration of uplift towards
present.
Our research was supported by the OTKA PD83610, PD100315, NK60455, K062478,
K83150 and F042799, the French-Hungarian Balaton-Tét Project (FR-32/2007;
TÉT_11-2-2012-0005), the Bolyai János Scholarship of the Hungarian Academy of
Sciences and by the “Lendület” program of the Hungarian Academy of Sciences
(LP2012-27/2012).
The 10Be measurements performed at the ASTER AMS national facility (CEREGE, Aix en
Provence) were supported by the INSU/CNRS, the French Ministry of Research and Higher
Education, IRD and CEA. The gamma-spectrometry measurements and part of the
preparation of the luminescence samples were carried out at the Leibniz Institute for Applied
Geophysics, Hannover, Germany. |
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