Clay mineralogy of Cape Roberts sediment cores ...
The clay mineral assemblages of the ca. 1600 m thick Cenozoic sedimentary succession recovered at the CRP-1, CRP-2/2A and CRP-3 drill sites off Cape Roberts on the McMurdo Sound shelf, Antarctica, were analysed in order to reconstruct the palaeoclimate and the glacial history of this part of Antarct...
Main Authors: | , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
PANGAEA
2005
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Subjects: | |
Online Access: | https://dx.doi.org/10.1594/pangaea.738196 https://doi.pangaea.de/10.1594/PANGAEA.738196 |
Summary: | The clay mineral assemblages of the ca. 1600 m thick Cenozoic sedimentary succession recovered at the CRP-1, CRP-2/2A and CRP-3 drill sites off Cape Roberts on the McMurdo Sound shelf, Antarctica, were analysed in order to reconstruct the palaeoclimate and the glacial history of this part of Antarctica. The sequence can be subdivided into seven clay mineral units that reflect the transition from humid to subpolar and polar conditions. Unit I (35-33.6 Ma) is characterised by an almost monomineralic assemblage consisting of well crystalline, authigenic smectite, and therefore does not allow a palaeoclimatic reconstruction. Unit II (33.6-33.1 Ma) has also a monomineralic clay mineral composition. However, the assemblage consists of variably crystallized smectite that, at least in part, is of detrital origin and indicates chemical weathering under a humid climate. The main source area for the clays was in the Transantarctic Mountains. Minor amounts of illite and chlorite appear for the first time in Unit III ... : Supplement to: Ehrmann, Werner; Setti, Massimo; Marinoni, L (2005): Clay minerals in Cenozoic sediments off Cape Roberts (McMurdo Sound, Antarctica) reveal palaeoclimatic history. Palaeogeography, Palaeoclimatology, Palaeoecology, 229(3), 187-211 ... |
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