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  • The Ocean Drilling Program (ODP) has been the largest cooperative marine geology program in history. The Australian Antarctic Division contributed to the Australian ODP budget while ODP was drilling in Antarctic or sub-Antarctic waters. Although initially related to ODP Leg 120 on Kerguelen Plateau (1988), the spirit of this project can also extend to Leg 188 (2000). These involvements have been primarily on foraminifera from the Cretaceous and Neogene but have also contributed to understanding of the sediments and changes of environment with time. A lot has been published and further papers are in press or in preparation. Leg 183 involvement was invited and turned down but Pat Quilty was then asked to present one paper on Late Cretaceous benthic foraminifera (published) and to act as external editor for the volume. This work is now almost final and is available on the WWW. Some sample data are available for download at the url below. For complete datasets, see the ODP website. The fields in this dataset are: Sample Accessory Depth (metres below surface) Species Planktonic percentage Barren

  • A collaborative Italian/Australian marine geoscience research voyage to the George Vth Land sector of the East Antarctic continental margin was carried out between 11th February and 20th March, 2000, on board the of the RV Tangaroa. The cost of the expedition was shared jointly by the Italian and Australian National Antarctic Research Programs. Twenty four scientific personnel from 13 institutions participated in the expedition. The geophysical data collected includes a total of 1827 km of multi-channel seismic data and 562 km of Chirper sonar data. A total of 11 gravity cores, 28 piston cores, 18 surface grabs and 11 short trigger cores were collected on the voyage. Water profile (CTD) measurements and water samples were collected at nine stations and seabed bottom photographs were made at 11 stations. The expedition discovered and mapped a shelf sediment drift deposit covering about 400 km2 lying in an greater than 800m deep section of the George Vth basin west of the Mertz Glacier. It is a true 'drift' deposit, since these sediments exhibit a patchy distribution, large-scale bedforms, contain foreset bedding and display a depositional architecture indicative of contour-parallel sediment transport. A significant observation is that the drift thins to the north into an acoustically-transparent veneer; this observation implies that the drift is sourced from the outer continental shelf, with sediment being transported landwards, across the shelf and into an 850m deep inner shelf basin. The 'Mertz Drift' is over 35 m thick and core samples demonstrate that it is composed of laminated, anoxic, gelatinous olive green, silicious mud and diatom ooze (SMO). Preliminary shipboard counts of the laminae suggest a thickness of from 4 to 20mm, with a mean of about 7mm. While the lower sediments are laminated, there is a 20 to 50cm thick sandy drape at the surface over the whole of the drift. This suggests that a recent (late Holocene) change in the depositional environment has occurred, possibly related to changes in the extent of the nearby Mertz Glacier tongue, current regime and/or to the persistence of sea ice over the shelf area. Multi-channel seismic data show the occurrence of foreset beds at the shelf break, interpreted as having been deposited by ice streams that grounded on the outer shelf during glacial maxima. On the shelf, the seismic character of the seafloor exhibits highly reflective, parabolic reflectors suggestive of crystalline basement, cropping out at the seafloor. Northwards of these basement outcrops, the water depth increases to over 1,100 m which is the George Vth Basin. The basin coincides with an abrupt transition in seismic character from acoustic basement in the south to seaward (northeasterly) dipping reflectors. On the continental rise, seismic sections were taken across a contourite drift deposit and submarine canyon system in 2500 to 3500 m water depth. Piston cores were collected along the profile of one drift deposit which gave a preliminary Mid-Pliocene age to truncated strata that crop out on the drift's steeper lee side. These data will provide useful site-survey information in support of a proposal sent to the Ocean Drilling Program under the auspices of the SCAR-ANTOSTRAT project for drilling key sites along the Antarctic margin.

  • Preliminary data set contains details of cores processed (eg. sample name/interval, dry weights, reactions, notes) and the methodology used. The future data set will document diatoms observed and counted for each sample. This project also has links to ASAC project 1044 (ASAC_1044), the Wilkes Land Glacial History (WEGA) project. WEGA cores from both the continental shelf (PC7,11,12) and slope (PC19, 20, 21) region have been silica-selectively processed for their diatom content (see methodology file for details). The slides are mounted for quantitative assessment. Details of the cores that have been prepared are listed in the file WEGA_cores.csv in the downloadable dataset. Additional silica-selective slides of the surface sediments on the continental shelf were processed for quantitative assessment. Details of the samples and their locations are listed in the file sediment_samples.csv in the downloadable dataset. There have been no publications from the prepared slides as of the 15/04/02. An unpublished Honours Thesis uses limited diatom counts from slides prepared from PC 12. (Ms J. Erbs 2001). Title to be forthcoming. Any further enquiries referring to sample availability, curation, additional samples or publications arising from this material should be directed to Dr L. Armand. The fields in this dataset are: dry weight (gm) Sol A* reaction HCL reaction final dilution notes cm depth bottom depth latitude longitude core depth

  • At Loewe Massif and Amery Oasis, samples were taken; - for sediment analysis (XRF geochemistry and grain size) - for geochronology (cosmogenic isotope analysis). The custodian for these samples is Dr Damian Gore, Macquarie University. Lake sediment samples were taken from Lake Terrasovoje, Radok Lake and Beaver Lake. The custodian for these lacustrine samples is Dr Martin Melles, Leipzig University. The dataset also includes weather/meteorological observations. Further work in project 1071 was also completed as part of PCMEGA. The fields in this dataset are: Date Site Latitude Longitude Time Altitude Temperature Pressure Wind direction Wind Speed Cloud Relative Humidity