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  • 40Ar/39Ar geochronology data of basalt samples from the Kerguelen Plateau and Broken Ridge The samples include basalts from ODP drilling cores and dredge sites. The drilling core samples were stored in the Kochi Core Centre, Japan and the dredged samples were stored in the National Museum of Natural History, France. Analytical methods of the 40Ar/39Ar geochronology data: Samples were crushed and minerals/groundmass were separated using a Frantz magnetic separator. Plagioclase, pyroxene, amphibole, sericite, and basaltic glass crystals and groundmass were separated from either the 125–212 μm or the 212–355 μm size fractions using a Frantz isodynamic magnetic separator. Minerals and groundmass were subsequently hand-picked grain-by-grain under a binocular stereomicroscope. Plagioclase and groundmass were further leached using diluted HF (2N) for 5 minutes and thoroughly rinsed in distilled water. Samples were loaded into several large wells of 1.9cm diameter and 0.3 cm depth aluminium discs. The discs were Cd-shielded to minimise undesirable nuclear interference re-actions and irradiated for 40 hours in the Oregon State University nuclear reactor (USA) in the central position. The samples were irradiated alongside FCs and GA1550 standards, for which ages of 28.294 ± 0.037 Ma and 99.738 ± 0.100 Ma were used, respectively. The 40Ar/39Ar analyses were performed at the Western Australian Argon Isotope Facility at Curtin University. The samples were step-heated using a continuous 100 W PhotonMachine© CO2 (IR, 10.4 µm) laser fired on the crystals during 60 seconds. Each of the standard crystals was fused in a single step. The gas was purified in an extra low-volume stainless steel extraction line of 240cc and using one SAES AP10 and one GP50 getter. Ar isotopes were measured in static mode using a low volume (600 cc) ARGUS VI mass spectrometer from Thermofisher© set with a permanent resolution of ~200. Measurements were carried out in multi-collection mode using four faradays to measure mass 40 to 37 and a 0-background compact discrete dynode ion counter to measure mass 36. We measured the relative abundance of each mass simultaneously using 10 cycles of peak-hopping and 33 seconds of integration time for each mass. Detectors were calibrated to each other electronically and using air shot beam signals. The raw data were processed using the ArArCALC software. The criteria for the determination of plateau are as follows: plateaus must include at least 70% of 39Ar released. The plateau should be distributed over a minimum of 3 consecutive steps agreeing at 95% confidence level and satisfying a probability of fit (P) of at least 0.05. Plateau ages are given at the 2σ level and are calculated using the mean of all the plateau steps, each weighted by the inverse variance of their individual analytical error. Uncertainties include analytical and J-value errors.

  • This dataset represents the collected work arising from ASAC projects 263, 351, 497 and 716 (ASAC_263, ASAC_351, ASAC_497, ASAC_716). The data are pooled together into a single excel file, and presented by year. Descriptions/explanations of acronyms used are given at the bottom of each spreadsheet. One worksheet also details all publications arising from (and related to) the four ASAC projects. The full titles of the four ASAC projects are: ASAC 263: Metamorphic Evolution and Tectonic Setting of Granulites from Eastern Prydz Bay ASAC 351: The Role of Partial Melting in the Genesis of Mafic Migmatites and Orthogenesis within the Rauer islands ASAC 497: Structural and Chemical Processes in Granulite Metamorphism: the Rauer Group and Brattstrand Bluffs Region, Prydz Bay ASAC 716: Archaean Crustal Accretion Histories and Significance for Geological Correlations Between the Vestfold Block and Rauer Group The fields in this dataset are: Archive Collector Sample Number Location Location Code Latitude Longitude Field description Collected for Reported in Comments Type Grid reference Worker

  • The SCAR Spatial Data Model has been developed for Geoscience Standing Scientific Group (GSSG). It was presented to XXVII SCAR, 15-26 July 2002, in Shanghai, China. The Spatial Data Model is one of nine projects of the Geographic Information Program 2000-2002. The goal of this project is 'To provide a SCAR standard spatial data model for use in SCAR and national GIS databases.' Activities within this project include: 1. Continue developing the SCAR Feature Catalogue and the SCAR Spatial Data Model 2. Provide SCAR Feature Catalogue online 3. Creation and incorporation of symbology 4. Investigate metadata / data quality requirements 5. Ensure compliance to ISO TC211 and OGC standards Source: Spatial data are increasingly being available in digital form, managed in a GIS and distributed on the web. More data are being exchanged between nations/institutions and used by a variety of disciplines. Exchange of data and its multiple use makes it necessary to provide a standard framework. The Feature Catalogue is one component of the Spatial Data Model, that will provide the platform for creating understandable and accessible data to users. Care has been taken to monitor the utility of relevant emerging ISO TC211 standards. The Feature Catalogue provides a detailed description of the nature and the structure of GIS and map information. It follows ISO/DIS 19110, Geographic Information - Methodology for feature cataloguing. The Feature Catalogue can be used in its entirety, or in part. The Feature Catalogue is a dynamic document, that will evolve with use over time. Considerable effort has gone into ensuring that the Feature Catalogue is a unified and efficient tool that can be used with any GIS software and at any scale of geographic information. The structure includes data quality information, terminology, database types and attribute options that will apply to any GIS. The Feature Catalogue is stored in a database to enable any component of the information to be easily viewed, printed, downloaded and updated via the Web.

  • Heard Island Expedition, 16 November 1986 to 21 January 1987, report written by Rod Ledingham, Officer in Charge. Taken from the report: The 1986-87 expedition was the second in a series of three consecutive expeditions planned to conduct new scientific work and to check on changes since the early wintering years from 1948-1954 and more recent sporadic visits by various government and private expeditions. We were dropped off at Heard Island on the 14th November 1986 by the Nella Dan. The main thrust of this expedition was originally to have been geological but this was later expanded to cover biology and archaeology. Transport was provided by three Hughes 500 helicopters, old faithfuls VH-BAD piloted by John Robertson and VH-BAG piloted by Doug Crossan, and a new arrive from NZ, VH-HED flown by Phillip Turner, to provide speedy access to all areas of rock, either coastal or at high altitude on the mountain. Of particular interest to the geologists were the lavas of the January 1985 Big Ben eruption spotted by observers including Dick Williams, on the French vessel Marion Dufresne. Despite some initial doubts about the possibility of flying, or even holding, aircraft at Heard for any length of time, and numerous relatively minor problems with weather and wind blown volcanic sand, the operation went very well and a great deal of new ground was covered, including several flights to the summit of Big Ben and the discovery of a new active crater and the expedition lava flows on the south-western slopes at Cape Arkona. Two geologists accompanied the expedition, Jane Barling and Graeme Wheller. Geological mapping of the whole island was carried out by Jane where access was not too difficult or dangerous. Jane had previously worked on the samples brought back from Long Ridge and the summit by the Heard Island Expedition (private) on Anaconda II in 1983. The original map produced by Ainsworth in 1947 will be greatly improved when the material has been studied in more detail. The second geologist Graeme studied the relationships of the more recent lavas and attempted to get samples from the summit vent. The failure to do so was somewhat ameliorated by the finding of the new lava which it appears had emanated from the summit vent pipe and samples of summit rock were therefore available from 700m above Cape Arkona. Further information about the botanical and biological work is available in the report.

  • The snapshot (originally produced on CD for a conference) was produced by the Australian Antarctic Data Centre for distribution to Heard Island expeditioners in the 2003/2004 season. The snapshot contained all publicly available data held by the Australian Antarctic Data Centre related to Heard Island at the time of production. The snapshot also contained all metadata held by the AADC at the time of production. Furthermore, information is also included from: AADC's gazetteer biodiversity database satellite image archive gis shapefiles heard island wilderness reserve management plan Finally, freely available software needed to browse some of the data are also included.