| SPELEOTHEMS |
Xia et al. 2001 Lynds Cave, Tasmania Speleothem Data
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Xia, Q.K.;Zhao, J.-x.;Collerson, K.D. 2001 Early-Mid Holocene climatic variations in Tasmania, Australia: multi-proxy records
in a stalagmite from Lynds Cave. Earth and Planetary Science Letters Vol. 194, Issues 1-2, pp. 177-187.
| Data Coverage |
North: -41.58 * South: -41.58 |
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West: 146.25 * East: 146.25 |
Start Year: -6938 AD
End Year: -3131 AD
Data: Please Cite Data Contributors!
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Summary: Mass spectrometric uranium-series dating and C-O isotopic analysis of a
stalagmite from Lynds Cave, northern Tasmania, Australia provide a high-
resolution record of regional climate change between 5100 and 9200 yr
before present (BP). Combined d18O, d13C, growth rate, initial 234U/238U
and physical property (color, transparency and porosity) records allow
recognition of seven climatic stages: Stage I (>9080 yr BP) ¿ a relatively
dry period at the beginning of stalagmite growth evidenced by elevated
234U/238U; Stage II (9080¿8600 yr BP) ¿ a period of unstable climate
characterized by high-frequency variability in temperature and
bio-productivity; Stage III (8600¿8000 yr BP) ¿ a period of stable and
moderate precipitation and stable and high bio-productivity, with a
continuously rising temperature; Stage IV (8000¿7400 yr BP) ¿ the warmest
period with high evaporation and low effective precipitation (rainfall
less evaporation); Stage V (7400¿7000 yr BP) ¿ the wettest period with
highest stalagmite growth and enhanced but unstable bio-productivity;
Stage VI (7000¿6600 yr BP) ¿ a period with a significantly reduced
precipitation and bio-productivity without noticeable change in temperature;
Stage VII (6600¿5100 yr BP) ¿ a period of lowest temperature and
precipitation marking a significant climatic deterioration. Overall,
the records suggest that the warmest climate occurred between 8000 and
7400 yr BP, followed by a wettest period between 7400 and 7000 yr BP.
These are broadly correlated with the so-called 'Mid Holocene optimum'
previously proposed using pollen and lake level records. However, the
timing and resolution of the speleothem record from Lynds Cave are
significantly higher than in both the pollen and lake level records.
This allows us to correlate the abrupt change in physical property,
d18O, d13C, growth rate, and initial 234U/238U of the stalagmite at
~8000 yr BP with a global climatic event at Early-Mid Holocene transition.
More Info on Speleothems |
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Complete XML Record: noaa-cave-5435
(Last Revised: 2007-10-18 )
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