East Antarctic Terrestrial Environments

Two main pre-Quaternary sedimentary sequences recording glacial events are found on land in East Antarctica, the Sirius Group in the Transantarctic

Mountains and the Pagodroma Group in the Prince Charles Mountains flanking the Lambert Glacier (Fig. 10.2). The two sequences are quite different in character. The Sirius Group is a mainly terrestrial glacigenic succession whose age has proved highly controversial, with Pliocene, mid-Miocene or even older ages suggested. The Pagodroma Group is an ice-proximal fjordal sequence up to several hundred metres thick, and is well dated on the basis of in situ marine fossils. All these well-exposed deposits are important in unravelling the history of the EAIS, as they are the nearest

Figure 10.2: (a) Map of Antarctica showing key sites of investigations of on-shore pre-quaternary glacigenic sediments. (b) The distribution of known Sirius Group outcrops. (c) Location of the Pagodroma Group sites along the Lambert Graben (redrawn from Hambrey and McKelvey, 2000a; Hambrey et al., 2003).

Figure 10.2: (a) Map of Antarctica showing key sites of investigations of on-shore pre-quaternary glacigenic sediments. (b) The distribution of known Sirius Group outcrops. (c) Location of the Pagodroma Group sites along the Lambert Graben (redrawn from Hambrey and McKelvey, 2000a; Hambrey et al., 2003).

deposits to the heart of the ice sheet, and yield valuable information concerning palaeogeography and palaeoclimate.

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