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  • Several grounding zone wedges were left on the floor and flanks of Prydz Channel in western Prydz Bay by the Lambert Glacier during the last glacial cycle. Seismic profiles indicate that vertical accretion at the glacier bed was the most important depositional process in forming the wedges, rather than progradation by sediment gravity flows. Sidescan sonographs reveal extensive development of flutes on the sea floor inshore from the wedges, indicating deformable bed conditions beneath the ice. The region inshore of the east Prydz Channel wedge features extensive dune fields formed by currents flowing towards the grounding zone. This orientation is consistent with models of circulation beneath ice shelves in which melting at the grounding line generates plumes of fresher water that rise along the base of the ice shelf, entraining sea water into a circulation cell. The Lambert Deep is surrounded by a large composite ridge of glacial sediments. Internal reflectors suggest formation mostly by subglacial accretion. The sea floor in the Lambert Deep lacks dune fields and shows evidence of interspersed subglacial cavities and grounded ice beneath the glacier. The absence of bedforms reflects sea floor topography that would have inhibited the formation of energetic melt water-driven circulation.

  • The Rayner Complex of East Antarctica is exposed between 45??80?E in the Enderby Land through Princes Elizabeth Land sector of East Antarctica. It is known to correlate with parts of present day India and to have been deformed and metamorphosed at high grades in the earliest Neoproterozoic (990-900 Ma). The age and origin of the protolith rocks of the Rayner Complex however remains largely unknown, as does the tectonic setting in which these rocks formed. New age data collected from the northern Prince Charles Mountains (eastern Rayner Complex), demonstrate that the pre-orogenic rocks from this region consist of: (1) volcanogenic and terrigenous sediments deposited between 1400 Ma and 1020 Ma in a magmatically active basin characterised by limited input from cratonic sources and, (2) probable syn-sedimentary granitoids dated to 1150 Ma. Our data confirm the continuity of the Rayner Complex into Prydz Bay, a region that preserves a remarkably similar geologic history but which is often differentiated from the Rayner Complex on the basis of a higher grade early Cambrian (~520 Ma) overprint. On the basis of our data we further conclude that the Rayner Complex protoliths likely in formed in a back-arc system that existed along the margin of the pre-Gondwana Indian craton. Anticlockwise P-T paths and high-T, low-P metamorphism associated with the inversion of the Rayner back-arc (990-900 Ma) suggest this event resulted from the accretion of a number of independent microplates, rather than continent-continent collision.

  • The sediments deposited beneath the floating ice shelves around the Antarctic margin provide important clues regarding the nature of sub-ice shelf circulation and the imprint of ice sheet dynamics and marine incursions on the sedimentary record. Understanding the nature of sedimentary deposits beneath ice shelves is important for reconstructing the icesheet history from shelf sediments. In addition, down core records from beneath ice shelves can be used to understand the past dynamics of the ice sheet. Six sediment cores have been collected from beneath the Amery Ice Shelf in East Antarctica, at distances from the ice edge of between 100 and 300 km. The sediment cores collected beneath this ice shelf provide a record of deglaciation on the Prydz Bay shelf following the last glaciation. Diatoms and other microfossils preserved in the cores reveal the occurrence and strength of marine incursions beneath the ice shelf, and indicate the varying marine influence between regions of the sub-ice shelf environment. Variations in diatom species also reveal changes in sea ice conditions in Prydz Bay during the deglaciation. Grain size analysis indicates the varying proximity to the grounding line through the deglaciation, and the timing of ice sheet retreat across the shelf based on 14C dating of the cores. Two of the cores contain evidence of cross-bedding towards the base of the core. These cross-beds most likely reflect tidal pumping at the base of the ice shelf at a time when these sites were close to the grounding line of the Lambert Glacier.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.

  • The Antarctic field notebooks contain the geological observations recorded by Bureau of Mineral Resources geologists during their trips to Antarctica between 1948 – 1980s. Files include a scanned copy of the original handwritten field notebook, transcription of the notebook’s contents transcribed by volunteers and validated by an experienced geologist, and a csv file of the transcription with Text Encoding Initiative (TEI) tags. The original Antarctic field notebooks are held at the N.H. (Doc) Fisher Geoscience Library at Geoscience Australia, Canberra.