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| Titel |
Local and regional oscillations of carbon and oxygen isotopes in terestrial carbonates |
| VerfasserIn |
Raminta Skipitytė, Migle Stancikaite |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250086562
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| Publikation (Nr.) |
 EGU/EGU2014-453.pdf |
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| Zusammenfassung |
| Stable isotope ratios of carbon and oxygen in sediment carbonates are used as a tool to
identify climatic changes in the past [1], [2]. Carbon is more related to humidity whereas
oxygen is thought to respond the temperature [2]. Nevertheless number of questions about
local, regional and global scale impacts to these records is left.
In this research work carbon and oxygen isotope ratios in lacustrine carbonates are
used to identify palaeoenvironmental dynamics of different locations. Samples of
lacutrine carbonates were obtained from 8 sequences of different sites in Lithuania (4),
Poland (1), Belarus (1) and Kaliningrad (1). Every sequence was divided into 2 cm
intervals.
The study showed differences in average carbon and oxygen isotope ratios between
Lithuania and other countries (Poland, Belarus and Kaliningrad). Carbon and oxygen isotope
ratios in 4 sites in Lithuania are:
¯U la δ13C -4.72± 2.11, o and δ18O -9.46± 1.9, o ; Zervynos δ13C -4.79± 1.82, o and
δ18O -9.57± 1.69, o ; Rudnia δ13C -4.94± 7.53, o and δ18O -9.3± 3.92, o ; Pauliai δ13C
-4.15± 0.67, o and δ18O -9.94± 1.07, o :
In other countries:
Poland δ13C -1.07± 1.94, o and δ18O -7.69± 0.95, o ; Belarus δ13C 0.97± 1.94, o
and δ18O -7.61± 1.42, o ; Kaliningrad δ13C -1.14± 1.43, o and δ18O -6.51± 1.00, o
:
Average stable carbon and oxygen isotope values from four sites in Lithuania were
-4.65 o for carbon and -9.51 o for oxygen. Despite homogeneity of average isotope
signals in these four sites there are relatively large oscillations of isotopic values in
Rudnia and relatively small in Pauliai. These oscillations could be related to local
characteristics of particular place such as environmental conditions, water balance, input of
terrigenous materials into basin, etc. Total amount of CaCO3 could also play a
significant role in reconstructing palaeoenvironment from stable isotopes and creating
isomaps.
The comparison of isotope records from different locations could enable to separate local,
regional and even global environment condition impact to isotopic values in the
past.
1. Hammarlund, Dan, et al. "Climate and environment during the Younger Dryas (GS-1)
as reflected by composite stable isotope records of lacustrine carbonates at Torreberga,
southern Sweden." Journal of Quaternary Science 14.1 (1999): 17-28.
2. Makhnach, N., et al. "Stable oxygen and carbon isotopes in Late Glacial–Holocene
freshwater carbonates from Belarus and their palaeoclimatic implications." Palaeogeography,
Palaeoclimatology, Palaeoecology 209.1 (2004): 73-101. |
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