Oligocene and Pliocene interglacial events in the Antarctic Peninsula dated using strontium isotope stratigraphy
Strontium isotope stratigraphy is used to date two interglacial-marine deposits in the Antarctic Peninsula region. On King George Island, interglacial pectinid-rich sediments in the Low Head Member of the Polonez Cove Formation give a strontium isotope stratigraphy age of 29.0+0.7−0.6 to 29.8+0.8−0....
Published in: | Journal of the Geological Society |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Geological Society of London
1997
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Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/514456/ https://doi.org/10.1144/gsjgs.154.2.0257 |
Summary: | Strontium isotope stratigraphy is used to date two interglacial-marine deposits in the Antarctic Peninsula region. On King George Island, interglacial pectinid-rich sediments in the Low Head Member of the Polonez Cove Formation give a strontium isotope stratigraphy age of 29.0+0.7−0.6 to 29.8+0.8−0.7 Ma (mid-Oligocene), which, in conjunction with previous K–Ar dating of volcanic rocks, indicates a glacial episode in the Antarctic Peninsula between middle Eocene (42.0 ±1.0 Ma) and mid-Oligocene time. In addition, an inter-glacial deposit (Pecten Conglomerate) from tectonically-elevated exposures on Cockburn Island is dated as Pliocene (3.5–5.3 Ma). Published data suggest these latter sediments were deposited under shallow marine conditions, which were warmer than those of present-day Antarctica. |
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