The final technical report for the Ti-Tree Basin Demonstration site for work undertaken as part of the Palaeovalley Groundwater Project

This GA Record report is one of a series of 4 reports undertaken by the GA Groundwater Group under the National Collaboration Framework Project Agreement with the Office of Water Science (in the Department of the Environment). The report was originally submitted to the OWS in July 2013, and subsequently reviewed by the Victorian and South Australian governments. The Otway Basin is a priority coal-bearing sedimentary basin that is not currently slated for Bioregional Assessment programme research in the initial tranche of work.

This GA Record report is one of a series of 4 reports undertaken by the GA Groundwater Group under the National Collaboration Framework Project Agreement with the Office of Water Science (in the Department of the Environment). The report was originally submitted to the OWS in July 2013, and subsequently reviewed by the SA government. The St Vincent Basin in South Australia is a priority coal-bearing sedimentary basin that is not currently slated for initial Bioregional Assessment.

Poster prepared for International Association of Hydrogeologists Congress 2013 In this study, AEM mapping validated by drilling has enabled the lateral extents and thickness of the Pliocene aquifers to be identified. The Pliocene in this area dominantly comprises the fluvial Calivil Formation, with the shallow marine Loxton-Parilla Sands restricted to the southernmost part of the area. Post-depositional warping, tilting and discrete offsets associated with neotoectonics are also recognised. Facies analysis indicates the Calivil was deposited in deep braided streams across a dissected sedimentary landscape. Overall, the sequence is fining-upwards, with evidence for progradation over the Loxton-Parilla. Channel fill materials comprise gravels and sands, and local fine-grained units represent abandoned channels and local floodplain sediments. Integration of textural and hydraulic testing data has revealed there are five hydraulic classes within the Calivil,. At a local scale (10s to 100s of metres), there is considerable lithological heterogeneity, however at a regional scale (kms), sands and gravels are widely distributed with particularly good aquifers developed in palaeochannels and at the confluence of palaeo-river systems. Aquifer testing has revealed Calivil to be an excellent aquifer, with high storage capacity, and locally very high transmissivities (up to 50 l/s). Integration of the AEM data with borehole geophysical data (gamma, induction and NMR) and textural and pore fluid data has enabled maps of aquifer properties including groundwater salinity, porosity, storage and hydraulic conductivity to be derived. Overall, the multi-disciplinary approach adopted has enabled rapid delineation of new groundwater resources, and facilitated assessment of the Pliocene aquifers for managed aquifer recharge.

Poster prepared for International Association of Hydrogeologists Congress 2013 In this study, a multi-disciplinary systems mapping approach has completely revised our understanding of the age, stratigraphy, mode of deposition and landscape evolution of Lower Darling Valley (LDV) sediments within the north-western Murray Basin. The Cenozoic sequence in this area contains Paleogene and Neogene shallow marine, fluvial and shoreline sediments overlain by Quaternary lacustrine, aeolian and fluvial units. The surficial Quaternary fluvial units of the valley form a complex group of morphostratigraphic units which vary in their distribution, character and geomorphic expression through the study area. Resolving the distribution of these units has been particularly important for understanding surface-groundwater interactions. In the LDV Quaternary fluvial sequence, multiple scroll-plain tracts are incised into higher, older more featureless floodplains. Prior to this study, these were respectively correlated to the Coonambidgal and Shepparton Formations of the Riverine Plain in the eastern Murray Basin and associated with the subsequently discarded Prior Stream/Ancestral River chronosequence of different climatically controlled depositional styles. In contrast to that proposition, we ascribe all LDV Quaternary fluvial deposition to lateral-migration depositional phases of one style, though with more variable stream discharges and channel and meander-scroll dimensions. Successively higher overbank-mud deposition through time obscures scroll traces and provides the main ongoing morphologic difference. A new morphostratigraphic unit, the Menindee Formation, refers to the mostly older and higher floodplain sediments, where scroll traces are obscured by overbank mud which continues to be deposited by the highest modern floods. Younger inset scroll-plain tracts, with visible scroll-plain traces, are still referred to the Coonambidgal Formation. Another new stratigraphic unit, the Willotia beds, refers to even older fluvial sediments, now above modern floodplain levels and mostly covered by aeolian sediments. This work provides important insights into the nature of Australian Quaternary fluvial deposition, with important implications for hydrogeological processes, groundwater resources and the assessment of managed aquifer recharge options.

NOTE: removed on request: 25 May 2016 by Sundaram Baskaran GWATER is a corporate database designed to accommodate a number of existing project groundwater and surface water data sets in AGSO. One of the aims in developing the database as a corporate repository is to enable sharing between AGSO projects allowing re-use of data sets derived from various sources such as the State and Territory water authorities. The database would also facilitate an easier exchange of data between AGSO and these authorities. This document presents an overview of the current structure of the database, and describes the present data entry and retrieval forms in some detail. Definitions of all tables and data fields contained within them are listed in an appendix. The database structure will not remain static. Future developments, such as the integration of data directly out of the database into geographic information systems, are expected to lead to modifications in the database structure with possible addition of new tables or fields. Use of GWATER by a range of project areas will undoubtedly lead to different needs in accessing the data, resulting in the request for further development of the data access tools.

Poster prepared for International Association of Hydrogeologists Congress 2013 Surface-groundwater interactions are often poorly understood. This is particularly true of many floodplain landscapes in Australia, where there is limited mapping of recharge and discharge zones along the major river systems, and only generalised quantification of hydrological fluxes based on widely spaced surface gauging stations. This is compounded by a lack of temporal data, with poor understanding of how surface-groundwater interactions change under different rainfall, river flow and flood regimes. In this study, high resolution LiDAR, in-river sonar, and airborne electromagnetic (AEM) datasets (validated by drilling) have been integrated to produce detailed 3-dimensional mapping that combines surface geomorphology and hydrogeology. This mapping enables potential recharge zones in the river and adjacent landscape to be identified and assessed under different flow regimes. These potential recharge zones and groundwater flow pathways were then compared against the spatial distribution of discontinuities in near-surface and deeper aquitard layers derived from the AEM interpretation. These 3D mapping constructs provide a framework for considering groundwater processes. Hydrochemistry data, allied with hydraulic data from a bore monitoring network, demonstrate the importance of recharge during significant flood events. In many places, the AEM data also affirm the spatial association between fresher groundwater resources and sites of river and floodplain leakage. At a more localised scale, hydrogeochemical data allows discrimination of lateral and vertical fluxes. Overall, this integrated approach provides an important conceptual framework to constrain hydrogeological modelling, and assessments of sustainable yield. The constructs are also invaluable in targeting and assessing managed aquifer recharge (MAR) options.

Geoscience Australia was recently involved in the reconceptualisation of the hydrogeology of the Great Artesian Basin (GAB), as part of the Great Artesian Basin Water Resource Assessment. The project refined the understanding of key hydrostratigraphic units within the GAB. This brochure describes key aquifers in the GAB and is designed to be distributed with samples from the aquifers. Aquifers covered are the Winton-Mackunda, Cadna-owie-Hooray, Adori Sandstone/Springbok Sandstone, Hutton Sandstone and Precipice Sandstone. Brochure prepared for the International Association of Hydrogeologists Congress 2013, Perth, Australia

Layer 08B Base of Poolowanna Formation Surface produced for the Great Artesian Water Resource Assessment (GABWRA) by Geoscience Australia (http://www.ga.gov.au). This surface was created for 3D visualisation of the Base of Poolowanna Formation . The surface is available in the following formats 1. GOCAD surface (.ts) 2. ESRI grid 3. ASCII grid (.grd) Use limitations: 1. GOCAD surface requires program capable of reading GOCAD *.ts (triangulated surface) files 2. ASCII grid data requires re-interpolation by end-user resulting in minor differences to accompanying GOCAD *.ts surface This layer is part of a set comprised of: Layer 01 3-second Digital Elevation Model surface (catalogue #75990) Layer 02 Base of Cenozoic surface (catalogue #75991) Layer 03 Base of Mackunda Formation and equivalents surface (catalogue #76021) Layer 04 Base of Rolling Downs Group surface (catalogue #76022) Layer 05 Base of Hooray Sandstone and equivalents surface (catalogue #76023) Layer 06 Base of Injune Creek Group surface (catalogue #76024) Layer 07 Base of Hutton Sandstone surface (catalogue #76025) Layer 05-07 Base of Algebuckina Sandstone surface (catalogue #76952) Layer 08A Base of Evergreen and Marburg formations (catalogue #76026) Layer 08B Base of Poolowanna Formation (catalogue #76953) Layer 09 Base of Precipice Sandstone and equivalents surface (catalogue #76027) Layer 10 Base of Jurassic-Cretaceous sequence surface (catalogue #76028) This dataset and associated metadata can be obtained from www.ga.gov.au, using catalogue number 76953.

Freshwater coastal aquifers provide an important resource for irrigated agriculture, human consumption and the natural environment. Approximately 18 million people live within 50 km of the coast in Australia, and many coastal communities are reliant on groundwater. These coastal aquifers are vulnerable to seawater intrusion (SWI) - the landward encroachment of seawater - due to their close proximity to the ocean. To assess the threat of SWI in Australia, a comprehensive literature review was undertaken with input from state/territory agencies. The literature review, in combination with contributions from stakeholders, identified sites within each of the states and the Northern Territory where SWI had been reported or where it was considered to be a serious threat. International Association of Hydrogeologists 2013 Congress poster