The cartographic collection of the Doc Fisher Geoscience Library consists of the maps and air photos created or acquired by agency staff since the formation of BMR in 1946. This includes maps produced by agencies which have merged with these over the years, such as AUSLIG. Maps held include: Australian geological map series (1:250,000, 1:100,000 and the 1 mile series); topographic maps produced by NATMAP and its predecessors (1:250,000, 1:100,000 and 1:50,000) - latest editions only; various Australian geochemical, geophysical and other thematic maps; geoscience map series from other countries acquired on an exchange basis, including some with accompanying explanatory notes; Non-series maps acquired by donation or exchange; atlases. The Air photos are predominantly those used for mapping Australia and, to a lesser extent, Papua New Guinea and Antarctica, by BMR/AGSO from the 1940s to the 1980s. Geographical coverage of the sets is not complete, but many individual photos are unique in that they have pin points, overlays or other markings made by teams in the field. The Papua New Guinea photographs in the collection may, in many cases, be the only existing copies. Flight diagrams are also held for many (but not all) sets of air photos. Some other related materials, such as montages of aerial photographs (orthophotos), are also represented in the collection.

Executive Summary Key Scientific Results and the Wallis Lake System. The key results of the survey are summarised in Table A. The oxygen fluxes into the sediments vary about two-fold between all sites. The oxygen fluxes measured here are typical, but are in the low to medium range of other fluxes in Australian estuaries. These oxygen fluxes represent winter rates only. We speculate oxygen flux into the sediments will probably be higher in spring, as a result of typical 'spring bloom' conditions, increased temperatures (10 oC or more), fresh water and nutrient runoff from the catchment, and higher carbon and nutrient loads to sediments. The carbon fluxes (TCO2) measured are indicative of the amount of organic carbon oxidised in the sediments. When O2 and TCO2 fluxes are about the same, then oxygen reduction accounts for most carbon oxidised. This was found at all sites except Wallis Creek (Site 3), where we infer that some sulphate reduction was occurring in near-surface sediments at the time of the survey. The carbon flux data are also indicative of a minimum carbon load to the sediments and these have been used to make an assessment of trophic status of sites based upon work done by Nixon (1995) (oligotrophic (O), mesotrophic (M) and eutrophic (E)). We use the O, M, E notations in a qualitative context only. Most sites in Wallis Lake have a mesotrophic status. The data from the Coolongolook River (Site 1) indicate that, in addition to organic matter, other reduced substances (perhaps metallic sulphides) are consuming oxygen. The % denitrification efficiency is emerging as a potential indicator of water and sediment quality. Because N is probably most important in controlling primary productivity (and plant growth) in Australian estuaries the % denitrification efficiency, when high, is indicative of most N being lost from the system as N2 gas. Conversely when low, this measuare indicates most N is retained in the system and, as such, could result in deteriorating water quality. On this basis all sites currently have 'good' water quality with denitrification efficiencies between 85 to 100 %. Some other modelling work indicates that a critical denitrification efficiency of about 40 % is indicative of deteriorating water quality. The sediment fluxes of phosphorus indicate that the sediments are a trap for P released from organic matter at the sediment water interface. There is no evidence for a release of P from sediments as a result of catchment P loadings Site Comparisons. The % denitrification efficiency indicator has been summarised above. All sites are ranked equally, and this indicator suggests no current risk to water quality because of poor N cycling in sediments. The TS % (total sulphur) content of the sediments is indicative of sulphate reduction occurring in the sediments. All sites have TS contents above background levels and do indicate that sulphate reduction has been occurring in these sediments. The data from the benthic chambers indicate that only at one site (Wallis Creek) was sulphate reduction occurring in the sediments at the time of the survey. The surface sediment (0 - 1 cm) TS data are integrated over about 10 year period (at sedimentation rates of about 1 mm/yr). We suggest that sulphate reduction is more likely to occur during the summer months when primary productivity is probably higher and the water column is more likely to be stratified. Sulphate reduction produces reduced sulphides in the sediments that may interfere with the nitrification process and reduce denitrification efficiency. We rank the 'risk' of deteriorating water quality at these sites in the following order: Site 2 > 4 > 3 > 1 > 5.

AGSO and in collaboration with Nigel Press and Associates, AUSLIG and Radarsat International (RSI) have undertaken an interpretative study of hydrocarbon migration and seepage in the offshore Bonaparte and Browse Basins, North-Western Australia. The study used Radarsat images, detailed water column Geochemical Sniffer and Airborne Laser Fluorosensor data, acquired over a number of many years. The intrepertations derived from these seepage technologies were compared and contrasted, and then intergrated with a wide variety of petroleum geological information, including regional seismic data, isopach maps, key reservoirs, source and sealing units and fault maps. All the data and many more have been placed into a 'regional' ArcView GIS associated with the final reports, Acrobat and Powerpoint files.

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The current perception is that rocks of the tonalite-trondhjemite-granodiorite (TTG) suite are the dominant Archaean granite type, that only become less important towards the end of the Archaean with the onset of significant reworking of older continental crust and the production of more potassic granites. This broadly established sequence is, however, oversimplified. Clearly different granites, including high-Mg varieties, alkaline/sub-alkaline granites, and granites with A-type affinities, are also important in the Archaean. More importantly, the increasing recognition of granites with evidence for an enriched-mantle component is providing constraints on both crustal growth mechanisms and on possible tectonic environments. Archaean granites in Australia are best known from the Pilbara and Yilgarn Cratons, Western Australia. Both are examples of Archaean granite-greenstone terrains dominated (>65%) by granites (and orthogneisses). This paper compares and contrasts granites from the central and eastern parts of the Pilbara Craton (CEP) with those from the Eastern part of the Yilgarn Craton (EY). Geological data combined with a compilation of >1200 geochemical analyses are utilised to identify both broad regional granite groups and secular changes within the both regions. Although the cratons exhibit different pre-histories it is notable that they share a somewhat similar pattern of granite evolution. It is clear that the granite types in both the CEP and EY exhibit an overall tendency to become more potassic (higher LILE contents), but also more variable in composition with time. This reflects initial continental crustal growth, and subsequent reworking, to produce an increasingly mature and heterogeneous crust, occurring over a long period (eastern CEP), or very rapidly (EY, western CEP). There is also increasing evidence for enriched-mantle components in post 3.0 Ga magma production, in both the CEP and EY, that probably reflect subduction-environment processes. Finally, it is evident that TTG magmatism, often regarded as a voluminous characteristic of Archaean terrains, is, at the present exposure level, relatively poorly represented in both the Pilbara and Yilgarn cratons, and particularly the latter. Volumetrically, more important in these regions, are granites with a high pressure signature, that fall into a more felsic more potassic (LILE-richer) group, best thought of as transitional TTGs. The presence of such granites can be taken as indicative of the involvement of pre-existing felsic crust at the time of their genesis, unlike more typical TTGs.

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