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.

中文翻译：

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南设得兰群岛（南极洲）乔治王岛东部渐新世-中新世序列的岩石地层和年代学研究，以及冰川期与全球同位素事件的相关性

乔治王岛（南极半岛南设得兰群岛）以其陆地古环境记录而闻名，其中包括可能多达四个新生代冰川期的证据。岛上冰川成因露头的一个优点是它们与可以同位素测年的火山地层有关。作为一项新的测绘和年代学研究的结果，现在可以表明，乔治王岛东部许多地质单元的已发表地层学和年龄需要进行重大修订。波洛涅兹冰川的年代为C。26.64 ± 1.43 Ma（渐新世晚期（Chattian 阶段）），包括以前被认为是始新世冰川（“克拉科夫冰川”）证据的露头。紧随其后的是在相对较短的间隔（< 2 Ma）内形成的两个重要的火山事件（Boy Point 和 Cinder Spur 形成），这也在渐新世 Chattian 阶段爆发。梅尔维尔冰川的年代为C。21-22 Ma（可能 21.8 Ma；早中新世（Aquitanian 阶段）），Legru 冰期可能≤C。10 Ma（晚中新世或更早）。作为这项研究的结果，Polonez 和 Melville 冰川现在可以分别与增加对 Oi2b 和 Mi1a 同位素带的信心相关联，因此代表了主要的冰川事件。