Abstract
Late Cenozoic, subglacially erupted volcanic sequences are scattered throughout the Antarctic Peninsula. Two of the best preserved examples, at Mount Pinafore (Alexander Island; c. 5.5-6 Ma) and Brown Bluff (Graham Land; c. 1 Ma), are complete enough to be regarded as sequence holotypes for this uncommonly preserved eruptive/depositional setting. Despite a common glacial association, the sedimentary lithofacies in the two outcrops suggest flowing and ponded water conditions, respectively, indicating significant differences in the depositional palaeoenvironments. The original ice thicknesses exerted a major control on the lithofacies which resulted from each eruptive phase. At Mount Pinafore, the lithofacies were confined within a steep-sided valley during successive eruptions beneath thin (100-150 m?), wet-based ice. The much thicker succession at Brown Bluff is a tindar-tuya edifice, which formed within a small basin (probably 15 km across) confined by ice 400 m thick.
Original language | English |
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Pages (from-to) | 115-129 |
Number of pages | 15 |
Journal | Sedimentary Geology |
Volume | 91 |
Issue number | 1-4 |
DOIs | |
Publication status | Published - Jun 1994 |
Keywords
- Peninsula
- Pliocene
- Deposits
- Rocks