Oceanographic processes in the subantarctic region contribute crucially to the physical and biogeochemical aspects of the global climate system. To explore and quantify these contributions, the Antarctic Cooperative Research Centre (CRC) organised the SAZ Project, a multidisciplinary, multiship investigation carried out south of Australia in the austral summer of 1997-1998. Taken from the abstracts of the referenced papers: The SAZ project organised by the Antarctic CRC has a continuing program of moored sinking particle trap studies in the Aub-Antarctic and Polar Frontal zones southwest of Tasmania along 140 degrees E. The first deployment obtained weekly or higher resolution samples through the austral summer from September 1997 through February 1998 at three locations: the central Sub-Antarctic Zone (47 degrees S, traps at 1000, 2000 and 3800 m depth), the Sub-Antarctic Front (51 degrees S, 1 trap at 3300 m) and above the Southeast Indian Ridge in the Polar Frontal Zone (54 degrees S, 2 traps at 800 and 1500 m). The particles were analysed for total mass, inorganic carbon, total carbon, nitrogen, silicon, and aluminium. Hence values for organic carbon, biogenic silica, and lithogenics were obtained, and the mass fluxes calculated. This report details the sites, moorings, data from the current meters and sediment traps, and results of analyses performed on the collected sediment trap material. Sediment trap moorings were deployed from September 21, 1997 through February 21, 1998 at three locations south of Australia along 140 degrees E: at -47 degrees S in the central Subantarctic Zone (SAZ) with traps at 1060, 2050, and 3850 m depth, at-51 degrees S in the Subantarctic Front with one trap at 3080m, and at -54 degrees S in the Polar Front Zone(PFZ) with traps at 830 and 1580m. Particle fluxes were high at all the sites (18-32gm-2 yr-1 total mass and 0.5-1.4g organic carbon m-2 yr-1 at ~1000m, assuming minimal flux outside the sampled summer period). These values are similar to other Southern Ocean results and to the median estimated for the global ocean by Lampitt and Antia [1997], and emphasise that the Southern Ocean exports considerable carbon to the deep sea despite its "high-nutrient, low chlorophyll" characteristics. The SAZ site was dominated by carbonate (greater than 50% of total mass) and the PFZ site by biogenic silica (greater than 50% of total mass). Both sites exhibited high export in spring and late summer, with an intervening low flux period in December. For the 153 day collection period, particulate organic carbon export was somewhat higher in all the traps in the SAZ (range 0.57-0.84 gC m -L) than in the PFZ (range 0.31-0.53), with an intermediate value observed at the SAF (0.60). The fraction of surface organic carbon export (estimated from seasonal nutrient depletion, Lourey and Trull [2001]) reaching 1000 m was indistinguishable in the SAZ and PFZ, despite different algal communities.

Ice-rafted debris is characterised by coarse material with typically angular grains, transported within icebergs and deposted in the ocean as the icebergs melt. This iceberg rafted debris (IBRD) flux data submitted here, was calculated by quantifying the coarse sand fraction (CSF) as a percentage of the bulk sample (weight of grains in the 250 micron to 2 mm size fraction), the dry bulk density (DBD) and the linear sedimentation rate (LSR) (following Krissek et al., 1995, Patterson et al., 2014). A method for quantifying the IBRD flux uses the coarse sand fraction (CSF) as a percentage of the bulk sample, dry bulk density (DBD) and the linear sedimentation rate (LSR) (Krissek et al., 1995, Patterson et al., 2014): The CSF (250μm-2mm) was acquired from samples at 10cm intervals along KC14 by wet-sieving approximately 20g of sediment per sample. Authigenic grains and microfossils were removed from the samples under a microscope. The remaining material was weighed on a microbalance and calculated as a percentage of the bulk sample. The DBD was calculated by subsampling approximately 8cm3 of sediment from the same depth intervals and dividing the dry weight of the sediment by the volume of the subsampler. The LSR was approximated by dividing the distance (cm) between the calibrated bulk carbon ages by the difference in time (kyr). The IBRD flux was then quantified using the above equation for each depth interval.

Metadata record for data expected from ASAC Project 2915 See the link below for public details on this project. Petroleum contamination poses a major threat to Antarctic and subantarctic ecosystems because diesel and lubricants are persistent and, at poorly defined concentrations, are toxic in marine environments. This project will asses how quickly important components in these products are naturally depleted using a model field experiment. We will identify and quantify the non-degrading portions of the fuels, and assess the longevity and rate of removal of these. We will relate the chemical analysis data with biological data on organisms in the sea-bottom sediments, in order to assess which components of the fuels do most harm to the organisms. Project objectives: The overall objective is to better understand the long-term environmental impact of spilled petroleum products in Antarctic marine systems. Decades of Antarctic exploration have left a significant legacy of petroleum pollution on-land and in nearshore marine environments, particularly around human stations. The natural attenuation of spilled diesel and lubricants occurs slowly in cold climates, particularly once the pollutants have adsorbed onto marine sediments. Major programmes funded by the AAD have identified the location of spills, and the nature and fate of some of the pollutants. This project will address some of the significant uncertainties which still exist regarding the natural depletion and ecotoxicological impact of spilled diesel and lubricants in the marine environment. A new PhD student at Macquarie University will carry-out much of this work, in collaboration with the CI and investigators. The specific objectives are: 1. To develop a quantitative method using cutting edge two-dimensional gas chromatography-mass spectrometry (GCxGC-TOFMS) to identify the components of spilled diesel and lubricants, especially the complex mixtures of recalcitrant residues and the secondary products of alteration. 2. To calculate the rates of removal of pollutants in the marine environment by comprehensive statistical treatment of the chemical data-set, and to assess the processes by which this removal occurs (e.g. aerobic/anaerobic biodegradation, water-washing, etc). 3. To assess the degradation rates and longevity of pollutant components against the biology of the disturbed communities of microbes and microfauna in the same experiments, so as to form a hypothesis of which components of the complex mixtures have the most important ecotoxicological response and environment impact. 4. Using the most important single isolated or related groups of components, to test the specific ecotoxicological impact of each in the marine environment using a short-term field experiment and laboratory toxicity tests. Taken from the 2008-2009 Progress Report: Progress against objectives: 1. A GCxGC-FID was installed at Macquarie University. No TOFMS has been purchased yet, due to non-funding of ARC Lief grant application. No further progress made towards this objective. 2. We have a comprehensive dataset now of the rates of removal of hydrocarbon components of SAB from the SRE4 experiment. Detailed GC-MS has been carried out so as to track removal of components in much more detail than can be achieved by GC-FID alone. TPH data have been calculated. The data has been utilised in the draft of one paper by Shane Powell (Powell, Stark, Snape, Woolfenden, Bowman, Riddle; Effects of diesel and lubricant oils on Antarctic benthic microbial communities over five years) which has not been submitted yet, and in an early draft of a paper by PhD student Ellen Woolfenden (E. N. M. Woolfenden, G. Hince, S. Powell, S. Stark, J. Stark, I. Snape, S. George; Effects of diesel and lubricant oils on Antarctic benthic microbial communities over five years). 3. This has partly been done, and is being written up by the Powell et al. paper referred to above. Detailed analysis of which are the most toxic compounds of SAB awaits further work-up of the data. 4. The field season to carry out this test was postponed from 08/09 to 09/10. Taken from the 2009-2010 Progress Report: Progress against objectives: 1. An ARC LIEF grant application was successful and a TOFMS will be purchased from the funds gained in mid 2010. 2. So far the 0-1cm of 10cm cores of marine sediment spiked with Biodegradable lubricant, used lubricant, clean lubricant and Special Antarctic Blend (SAB) diesel have been analysed by gas chromatography coupled to a flame ionisation detector (GC-FID). Analyses by GC-FID allowed the Total Petroleum Hydrocarbon (TPH) concentration at each sample time to be calculated from statistical analysis. Further analyses were performed on the SAB sediments extractions by GC-MS (mass spectrometry). The chromatograms of the extractions were compared with chromatograms of standard mixtures of compounds and a compound identification library and thus, peaks were identified. From this peak identification, degradation patterns of compounds and groups of compounds could be seen; naphthalenes degrade less readily with increasing methyl groups but still degrade more readily than n-alkanes. From the analyses of the 0-1cm sediment extractions the most recalcitrant compounds were (adamantanes and diamantanes) and the most water soluble compounds were (naphthalenes and alkylnaphthalenes) in SAB diesel. The data has been written up in a draft paper by PhD student Ellen Woolfenden (E. N. M. Woolfenden, G. Hince, S. Powell, S. Stark, J. Stark, I. Snape, S. George; Effects of diesel and lubricant oils on Antarctic benthic microbial communities over five years). This paper will be submitted by May 2010. We also have started analysing the depth profiles for SAB in the SRE4 experiment. It is interesting to know as to whether any biodegradation patterns will be seen in the 1-10 cm depths of the sediment. Therefore the cores have been sectioned into 1 cm intervals and extracted at AAD. The extractions are awaiting analysis by GC-FID initially and GC-MS for further analysis. 3. This has partly been done, and is being written up by a Shane Powell et al. paper, that has not been published yet. Detailed analysis of which are the most toxic compounds of SAB awaits further work-up of the data. 4. The field season to carry out this test was carried out by Ellen Woolfenden in fieldseason 09/10. Samples have been collected and are stored at AAD. Marine sediment was collected and different portions were spiked with certain compounds from each of these groups as well as a selection of n-alkanes and SAB diesel as a comparison. These sediments have been extracted and are awaiting analysis by GC-MS to identify which of the compounds are depleted most readily within the experimental groups without the influence of other compounds present in SAB diesel. Ellen will be analysing them later in 2010. The dataset provided by Ellen Woolfenden contain a number of excel spreadsheets, as well as a word document providing further information about the data.

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.