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  • The Surface Hydrology Points (Regional) dataset provides a set of related features classes to be used as the basis of the production of consistent hydrological information. This dataset contains a geometric representation of major hydrographic point elements - both natural and artificial. This dataset is the best available data supplied by Jurisdictions and aggregated by Geoscience Australia it is intended for defining hydrological features.

  • This dataset maps the geomorphic habitat environments (facies) for 36 South Australian coastal waterways. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Most of the 36 coastal waterways have a "Modified" environmental condition (as opposed to "Near Pristine"), according to the National Land and Water Resources Audit definition.

  • This dataset maps the geomorphic habitat environments (facies) for 213 Queensland coastal waterways. This version of the dataset includes 73 newly mapped estuaries, classified as 'Near pristine'. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Southern and central Great Barrier Reef lagoon coasts have a broad spectrum of river, tide and wave- dominated estuaries.

  • This document represents part of Geoscience Australia's contribution to the National Estuaries Assessment and Management (NE) project, Theme 5 (Assessment and Monitoring), Task 5A 'Conceptual Models of Australian Estuaries and Coastal Waterways'. The report contains comprehensive conceptual models of the biophysical processes that operate in a wide range of estuaries and coastal waterways found around Australia. Geomorphic conceptual models have been developed for each of the seven types of Australian estuaries and coastal waterways. Each conceptual model comprises a three-dimensional block diagram depicting detailed summaries of the structure, evolutionary characteristics, and geomorphology of each coastal waterway type, which are ?overlain? by flow diagrams that depict some of the important biotic and abiotic processes, namely: hydrology, sediment dynamics, and nutrient dynamics. Geomorphology was used as the common 'base layer' in the conceptual models, because sediment is the fundamental, underlying substrate upon which all other estuarine processes depend and operate. In the conceptual models, wave-dominated systems are depicted as having a relatively narrow entrance that restricts marine flushing, and low water-column turbidity except during extreme events. Tide-dominated systems feature relatively wide entrances, which likely promote efficient marine flushing, very large relative areas of intertidal habitats, and naturally high turbidity due to strong turbulence induced by tidal currents. Strong evidence exists suggesting that estuaries (both wave- and tide-dominated) are the most efficient 'traps' for terrigenous and marine sediments, and these are depicted as providing the most significant potential for trapping and processing of terrigenous nutrient loads. Intertidal areas, such as mangroves and saltmarshes, and also the central basins of wave-dominated estuaries and coastal lagoons, are likely to accumulate the majority of trapped sediments and nutrients. Conceptual model diagrams, with overlays representing environmental processes, can be used as part of a decision support system for environmental managers, and as a tool for comparative assessment in which a more integrative and shared vision of the relationship between components in an ecosystem can be applied.

  • The Australian Flood Studies Database is available on line by Geoscience Australia. The database provides metadata on Australian flood studies and information on flood risk with a digital version where available. The purpose of the document is to guide new users in data entry and uploading of flood studies to a level acceptable for inclusion in the database.

  • The Australian Flood Studies Database is available on line by Geoscience Australia via the Australian Flood Risk Information Portal. The database provides metadata on Australian flood studies and information on flood risk with a digital version where available. The purpose of the document is to guide new users in data entry and uploading of flood studies to a level acceptable for inclusion in the database.

  • This project was conducted by Geoscience Australia in collaboration with the Water Science Branch of the Department of Water, Western Australia, to acquire baseline information supporting the condition assessment for Hardy Inlet. The project contributes to the Estuarine Resource Condition Indicators project funded by the Strategic Reserve of the National Action Plan for Salinity and Water Quality / National Heritage Trust and forms part of the Resource Condition Monitoring endorsed under the State (Western Australia) Natural Resource Management framework. Two surveys were undertaken in Hardy Inlet in September 2007 and April 2008 with the aim to develop an understanding of the historical environmental changes and current nutrient and sediment conditions for the purpose of developing sediment indicators to characterise estuary condition.

  • We examine surface sediment and water column total nutrient and chlorophyll a concentrations for 12 estuaries with average water depths <4 m, and calculated sediment loads ranging from 0.2 to 10.8 kg m-2 year-1. Sediment total nitrogen, phosphorus and organic carbon concentrations vary inversely with sediment loads due to: (i) the influx of more mineral-rich sediment into the estuaries; and (ii) increasing sediment sulfidation. Sediment total organic carbon (TOC) : total sulfur (TS) and TS : Fe(II) ratios correlated to sediment loads because enhanced sedimentation increases burial, hence the importance of sulfate reduction in organic matter degradation. Curvilinear relationships were found between a weathering index and organic matter 13C in sediment, and sediment load. The rising phase of the curve (increasing weathering, lighter isotopic values) at low to intermediate loads relates to soil erosion, whereas regolith or bedrock erosion probably explains the declining phase of the curve (decreasing weathering, heavier isotopic values) at higher sediment loads. The pattern of change for water column total nutrients (nitrogen and phosphorus) with sediment loads is similar to that of the weathering index. Most water quality problems occur in association with soil erosion, and at sediment loads that are intermediate for the estuaries studied. Limited evidence is presented that flushing can moderate the impact of sediment loads upon the estuaries.

  • For nearly nine months of the year the river proper is confined to a narrow channel two to three hundred feet wide. During the remainder of the year, however, the river is subject to periodical floodings resulting from heavy tropical rain on its water-shed and for periods of a week of more at a time the low level bridge is covered by flood water. The dislocation of rail traffic which results from these periodical floodings has been a matter of serious concern to the Queensland authorities for many years and a decision was made to construct a high level rail and road bridge to replace the existing structure. Construction was commenced, but before it proceeded far, it was considered desirable that the depth of the bedrock, previously examined, should be established without doubt. In view of the uncertainty of the depth to be drilled and the very considerable difficulty in drilling through alternating layers of drift sand and boulder wash, a request was made by the Co-ordinator General of Public works for Queensland for a geophysical investigation of the site. A survey was carried out by the geophysical section of the Commonwealth Bureau of Mineral Resources during August and September, 1947. The investigation of the results is far from complete but the seismic method gave such concise results that this preliminary statement is justified. Geology, geophysical methods, results, interpretation, and testing are discussed in this report.

  • The Commonwealth Flax Production Committee conducts a flax mill at Ballarat. The flax is first treated with water and 25,000 gallons per day are used in the process. After the treatment, the water is allowed to run to waste, and is at present being conducted through an earthen drain to natural drainage channels. This disposal of effluent water is not approved by the Ballarat Council, and other means of disposal have to be found. The objective of the present investigation was to determine if another borehole could be suitably sited to dispose of the effluent. The geology of the area, possibilities of disposal, and recommendations are discussed in this report. Two accompanying plates are included.