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| Titel |
Surface exposure dating of Holocene basalt flows and cinder cones in the Kula volcanic field (western Turkey) using cosmogenic 3He and 10Be |
| VerfasserIn |
Caroline Heineke, Samuel Niedermann, Ralf Hetzel, Cüneyt Akal |
| 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 |
250103013
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| Publikation (Nr.) |
 EGU/EGU2015-2414.pdf |
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| Zusammenfassung |
| The Kula volcanic field is the youngest volcanic province in western Anatolia and covers an
area of about 600 km2 around the town Kula (Richardson-Bunbury, 1996). Its alkali basalts
formed by melting of an isotopically depleted mantle in a region of long-lived continental
extension and asthenospheric upwelling (Prelevic et al., 2012). Based on morphological
criteria and 40Ar/39Ar dating, four phases of Quaternary activity have been distinguished in
the Kula volcanic field (Richardson-Bunbury, 1996; Westaway et al., 2006). The youngest
lava flows are thought to be Holocene in age, but so far only one sample from this
group was dated by 40Ar/39Ar at 7±2Âka (Westaway et al., 2006). In this study, we
analysed cosmogenic 3He in olivine phenocrysts from three basalt flows and one
cinder cone to resolve the Holocene history of volcanic eruptions in more detail. In
addition, we applied 10Be exposure dating to two quartz-bearing xenoliths found at the
surface of one flow and at the top of one cinder cone. The exposure ages fall in the
range between ~500 and ~3000Âyears, demonstrating that the youngest volcanic
activity is Late Holocene in age and therefore distinctly younger than previously
envisaged. Our results show that the Late Holocene lava flows are not coeval but
formed over a period of a few thousand years. We conclude that surface exposure
dating of very young volcanic rocks provides a powerful alternative to 40Ar/39Ar
dating.
References
Prelevic, D., Akal, C. Foley, S.F., Romer, R.L., Stracke, A. and van den Bogaard, P.
(2012). Ultrapotassic mafic rocks as geochemical proxies for post-collisional dynamics of
orogenic lithospheric mantle: the case of southwestern Anatolia, Turkey. Journal of Petrology,
53, 1019-1055.
Richardson-Bunbury, J.M. (1996). The Kula Volcanic Field, western Turkey: the
development of a Holocene alkali basalt province and the adjacent normal-faulting graben.
Geological Magazine, 133, 275-283.
Westaway, R., Guillou, H., Yurtmen, S., Beck, A., Bridgland, D., Demir, T.,
Scaillet, S. and Rowbotham, G. (2006). Late Cenozoic uplift of western Turkey:
Improved dating of the Kula Quaternary volcanic field and numerical modelling
of the Gediz River terrace staircase. Global and Planetary Change, 51, 131-171. |
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