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  • The palaeontology collection at the British Antarctic Survey is a unique and internationally important collection of specimens sourced predominantly from the Antarctic Peninsula and Scotia Arc. The collection was started in the 1940s and continues to be added to frequently through ongoing BAS research. Its importance lies not only in the fact that it is globally one of the main reference collections of Antarctic palaeontological material, but also in its high proportion of Mesozoic flora and fauna which can be used to understand evolutionary dynamics, continental movements and climatic changes over the past 250 ma. In addition to molluscs and other major animal phyla, the collection is particularly strong in plant material, ranging from fossilised wood and exceptionally preserved leaves to pollen and spores. Given the logistical challenges of sampling material from the Antarctic continent, this collection represents a wealth of taxa which were previously unknown to science and consequently houses a high number of taxonomic types. A project is underway to digitally catalogue the BAS Type and Figured fossil collection and make the data easily accessible to researchers worldwide. Currently the data from over 2000 fossil specimens are available online, together with high resolution photographs. Over the next year further specimens, including palynological samples, will be added to the database and photographs will be made available of the entire collection. Please direct any comments, questions or enquiries to: fossils@bas.ac.uk

  • The British Antarctic Survey holds one of the most extensive collections of Antarctic rocks and fossils anywhere in the world. These are predominately from the Antarctic Peninsula region and Scotia Arc, although there is also important material from areas such as the Ellsworth Mountains, Marie Byrd Land and the Transantarctic Mountains. Some of these specimens go back to the very earliest days of the Falkland Islands Dependencies Survey in the 1940s, and include collections made by the pioneer geologists at bases such as Hope Bay and Deception Island. Right from the outset, every specimen collected in Antarctica has been numbered and catalogued, and a vast reference archive is now available for use by the geoscience community. We currently have information relating to 150,000 field samples often with associated analysis data such as geochemistry. Additionally we hold a variety of data for nearly 500 marine cores. Metadata and data are stored digitally within a number of Oracle 10g database tables and for some datasets such as the type and figured fossil collection there is external access through a web interface. However, a significant number of datasets exist only in analog form and are held within the BAS archives organised by individual geologist. This abstract acts as an overview of the BAS geological data - both terrestrial and marine.

  • The British Antarctic Survey holds magnetic data measuring the plasmaspheric mass loading on magnetic field lines in Antarctica. The network of Low Power Magnetometer (LPM) instruments consists of permanent and temporary sites. The data is collected in 3 D fluxgate at up to 1 second and 1 nT resolution. Samples are taken once a second for 150 milliseconds at maximum power. This decreases to once a minute if power is low over the winter. Time and position is measured using an attached GPS system.

  • A transect of cores was taken from shelf to deep sea west of the Antarctic Peninsula off Marguerite Bay using a 12 m RVS piston corer, box corer and BGS vibrocorer deployed from RSS James Clark Ross cruise JR71 (12 days sea-time in 2001-2002). Successful coring and examination of sediments now on and immediately beneath the sea floor, which provided the deforming bed of the former ice stream, enhanced our understanding of conditions beneath ice streams. Data was collected as part of a project was to reconstruct the Late Quaternary dynamics of the Antarctic Peninsula Ice Sheet in Marguerite Bay and to compare sedimentation and ice-rafted debris records with the Larsen Ice Shelf area, on the other side of the Antarctic Peninsula. The mapping of streamlined sedimentary bedforms on the outer shelf has allowed the dimensions of a former fast-flowing ice stream present at the Last Glacial Maximum to be defined. This, in turn, enabled estimates of the past magnitude of ice flow through this glacial system to be calculated.

  • Geochemical analysis of rock samples acquired by dredging activities in the Scotia Sea between Feb and Mar 2004 aboard James Clark Ross (cruise no JR77). The initial aim of this project was to carry out a higher resolution geochemical study of mantle flow using existing samples. This confirmed flow from the Bouvet domain into the East Scotia Sea and placed constraints on flow pathways. The second stage was to sample further within the West Scotia Sea and to use elemental and isotope (Sr, Nd, Pb, Hf) analyses to fingerprint mantle provenance. The results were used to locate and investigate the nature of the Pacific-South Atlantic mantle domain boundary and thus to contribute to the understanding and quantification of global upper mantle fluxes.

  • Dredge sampling was carried out aboard the James Clark Ross (cruise no JR77 ) during Feb and Mar 2004. The dredge target area was along the eastern segments of the West Scotia Ridge, an ocean spreading centre which stopped spreading about 10 million years ago. The spreading centre has high topographic relief and contains an axial rift, which has flanks that are suitable for dredging. The plan was to map the spreading centre using the swath bathymetry system, and then to use this map to locate the best dredging sites. Thirteen dredges were successful in recovering oceanic rocks of mixed sizes, up to and including very large boulders and dredge paths of up to 1 km were followed.

  • Dredging for rock samples was conducted in the West Scotia Sea during James Clark Ross cruise no JR77 between Feb and Mar 2004. The aim was to acquire rock samples to constrain the history of the mantle beneath the Scotia Sea, from which the oceanic crust was derived by melting. Twenty days of rock dredging were conducted at fourteen sites in five main areas. Thirteen dredges were successful in recovering oceanic rocks of mixed sizes, up to and including very large boulders and dredge paths of up to 1 km were followed. The cruise also (remarkably) recovered fresh mantle peridotite nodules from the West Scotia Ridge, the first of its type - to our knowledge - from the world''s ocean ridge system.

  • Sediments cores collected aboard the RRS James Clark Ross (JR104) in the Bellingshausen Sea, 2004. This work was carried out as part of the first systematic investigation of the former ice drainage basin in the southern Bellingshausen Sea. Reconnaissance data collected on previous cruises JR04 (1993) and cruises of R/V Polarstern in 1994 and 1995 suggested that this area contained the outlet of a very large ice drainage basin during late Quaternary glacial periods. The data and samples collected allowed us to address questions about the timing and rate of grounding line retreat from the continental shelf, the dynamic character of the ice that covered the shelf, and its influence on glaciomarine processes on the adjacent continental slope.

  • The chemistry of mafic volcanic rocks and minor intrusions erupted on continents can be used to define the composition and history of subcontinental asthenospheric and lithospheric mantle domains. We have produced new and collated published data for Antarctica in order to identify mantle domains beneath the continent. Suitable material archived at the British Antarctic Survey, Cambridge, the result of previous geological research, was sampled and prepared for petrographic and geochemical analysis in the intervening period between field collection and sample arrival in the United Kingdom. Field information, petrography and raw geochemical data obtained from XRF (X-ray fluorescence), ICPMS (Inductively coupled plasma-mass spectrometer), TIMS (Thermal Ionization Mass Spectrometer), Ar/Ar analysis and Electron Microprobe analysis of rock samples collected from Palmer Land and Graham Land was used to define a geochemical profile of crust/mantle architecture beneath the Antarctic Peninsula.

  • Initial work during the 2001/2002 field season commenced with reconnaissance and sampling in northeast Palmer Land. Over a two month period, outcrop from the Welch Mountains to the Eternity Range was visited, the geology described, and mafic dyke samples collected for analysis. This was followed by a further two months based on the ship HMS Endurance, carrying out helicopter assisted sampling of numerous islands and coastal localities along the western and eastern margin of northern Graham Land. Approximately 200 rock samples (400kg of dyke and host rock at Palmer land and 80kg at nine localities in Graham Land) were collected.