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| Titel |
A long-term rock uplift rate for eastern Crete from exposure dating of marine terraces |
| VerfasserIn |
M. Strobl, R. Hetzel, S. Ivy-Ochs, V. Alfimov, P. W. Kubik, C. Fassoulas, L. Palumbo |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250020572
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| Zusammenfassung |
| Abstract
The island of Crete in the forearc of the Hellenic subduction zone has a rugged
topography with a relief exceeding 2 km. Rock uplift rates of 2-4 mm/a were estimated
previously from raised Late Holocene shorelines (Lambeck, 1995) but may not be
representative on longer timescales, because earthquakes with up to 9 m of coseismic uplift
have recently affected Crete (Stiros, 2001). Here we use marine terraces near Kato Zakros to
quantify the long-term rock uplift rate for eastern Crete. Our field investigations and
topographic profiles document a flight of at least 15 marine bedrock terraces carved into
limestone bedrock. Age constraints for the terraces were obtained by 36Cl exposure dating of
bedrock samples and 10Be dating of sandstone cobbles found on some terraces. Our results
suggest that the terraces T4 and T5 at elevations of 68 and 76 m, respectively, formed
during sea level highstands associated with marine isotope stage 5e, i.e. ~125 ka
ago. Correlating the other terraces (T1 to T11) to a sea-level curve for the Red Sea
(Siddall et al., 2003) indicates an uplift rate of 0.5-0.6 mm/a during the last 400 ka;
significantly lower than previous estimates based on the elevation of Late Holocene
shorelines.
References
Lambeck, K. (1995), Late Pleistocene and Holocene sea-level change in Greece and SW
Turkey - a separation of eustatic, isostatic and tectonic contributions. Geophys. J. Int. 122,
1022-1044.
Siddall, M., Rohling, E.J., Almogi-Labin, A., Hemleben, C., Meischner, D., Schmelzer,
I., and Smeed, D.A. (2003), Sea-level fluctuations during the last glacial cycle. Nature, 423,
853-858.
Stiros, S.C. (2001), The AD 365 Crete earthquake and possible seismic clustering during
the fourth to sixth centuries AD in the Eastern Mediterranean: a review of historical and
archaeological data. J. Struct. Geol., 23, 545-562. |
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