A lithostratigraphical and chronological study of Oligocene-Miocene sequences on eastern King George Island, South Shetland Islands (Antarctica) and correlation of glacial episodes with global isotope events

Smellie, John L.; McIntosh, William C.; Whittle, Rowan ORCID: https://orcid.org/0000-0001-6953-5829; Troedson, Alexa; Hunt, Richard J.. 2021 A lithostratigraphical and chronological study of Oligocene-Miocene sequences on eastern King George Island, South Shetland Islands (Antarctica) and correlation of glacial episodes with global isotope events. Antarctic Science, 33 (5). 502-532. https://doi.org/10.1017/S095410202100033X

Before downloading, please read NORA policies.

Preview

Text (Open Access) © The Author(s), 2021. Published by Cambridge University Press. a-lithostratigraphical-and-chronological-study-of-oligocene-miocene-sequences-on-eastern-king-george-island-south-shetland-islands-antarctica-and-correlation-of-glacial-episodes-with-global-isotope-ev.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (3MB) | Preview

Abstract/Summary

King George Island (South Shetland Islands, Antarctic Peninsula) is renowned for its terrestrial palaeoenvironmental record, which includes evidence for potentially up to four Cenozoic glacial periods. An advantage of the glacigenic outcrops on the island is that they are associated with volcanic formations that can be isotopically dated. As a result of a new mapping and chronological study, it can now be shown that the published stratigraphy and ages of many geological units on eastern King George Island require major revision. The Polonez Glaciation is dated as c. 26.64 ± 1.43 Ma (Late Oligocene (Chattian Stage)) and includes the outcrops previously considered as evidence for an Eocene glacial ('Krakow Glaciation'). It was succeeded by two important volcanic episodes (Boy Point and Cinder Spur formations) formed during a relatively brief interval (< 2 Ma), which also erupted within the Oligocene Chattian Stage. The Melville Glaciation is dated as c. 21–22 Ma (probably 21.8 Ma; Early Miocene (Aquitanian Stage)), and the Legru Glaciation is probably ≤ c. 10 Ma (Late Miocene or younger). As a result of this study, the Polonez and Melville glaciations can now be correlated with increased confidence with the Oi2b and Mi1a isotope zones, respectively, and thus represent major glacial episodes.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1017/S095410202100033X
ISSN:	0954-1020
Additional Keywords:	40Ar/39Ar, Kraków Glaciation, Polonez Glaciation, Melville Glaciation, Legru Glaciation, isotope zones
Date made live:	02 Aug 2021 15:23 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/529379

Actions (login required)

View Item

Document Downloads

More statistics for this item...