Speleothem-inferred paleoclimate records at 620-450 thousand years ago from northern Mediterranean
Abstract
The marine isotope stages 13 and 14 (MIS 13 and 14) from 565 to 480 thousand years ago (ka) is characterized by less significant glacial conditions in northern hemisphere. However, understanding sea-level change during this period, especially the termination VI at 533-530 ka, was still unclear. Here we present the 230Th-dated speleothem-inferred records of one drilled flowstone core from 620 to 450 ka in Basura cave, northern Italy. Carbonate δ18O records paced previous Mediterranean sea-level curves from MIS 13 to 15, supporting the interpretation of "source effect" on orbital-scale δ18O fluctuations. However, the warming event during MIS 13 at 533-480 ka indicated from Greenland pollen records is ambiguous in our sea-level sensitive records; the 1.5‰ changes in δ18O at Termination VI, similar to these of adjacent Mediterranean foraminifera, are relatively small compared to average 2-3‰ changes at other Terminations. An extra-long "interglacial" period with small sea-level variations at 620-500 ka in Basura record implies a limited extent of ice sheet in both north and south hemispheres.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMPP51F1427C
- Keywords:
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- 1009 Geochemical modeling;
- GEOCHEMISTRY;
- 4914 Continental climate records;
- PALEOCEANOGRAPHY;
- 4924 Geochemical tracers;
- PALEOCEANOGRAPHY;
- 4994 Instruments and techniques;
- PALEOCEANOGRAPHY