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Draft Genome Sequence of Caloramator australicus Strain RC3T, a Thermoanaerobe from the Great Artesian Basin of Australia ▿

Ogg, Christopher D.; Patel, Bharat K. C.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2011 EN
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66.63%
Caloramator australicus strain RC3T (JCM 15081T = KCTC 5601T) is the type strain of a newly identified thermophilic species, which was isolated from red microbial mats that thrive at 66°C in the runoff channel of a Great Artesian Basin bore (New Lorne bore, registered number 17263) in outback Queensland, Australia. The ability of the C. australicus strain to use metals as terminal electron acceptors has led to concerns that it could colonize and enhance corrosion of the metal casing of Great Artesian Basin bore well pipes and that this could subsequently lead to bore failure and loss of water availability for the community which is so reliant on it. The genome of the C. australicus strain has been sequenced, and annotation of the ∼2.65-Mb sequence indicates that the attributes are consistent with physiological and phenotypic traits.

Desulfotomaculum varum sp. nov., a moderately thermophilic sulfate-reducing bacterium isolated from a microbial mat colonizing a Great Artesian Basin bore well runoff channel

Ogg, Christopher D.; Patel, Bharat K. C.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
EN
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66.42%
A strictly anaerobic moderately thermophilic bacterium, designated strain RH04-3T (T = type strain), was isolated from a red colored microbial mat that colonizes a Great Artesian Basin (GAB) bore well (Registered Number 17263) runoff channel at 66 °C. The cells of strain RH04-3T were straight to slightly curved, sporulating, Gram-positive rods (2.0–5.0 × 1.0 μm) that grew optimally at 50 °C (temperature growth range between 37 and 55 °C) and at pH 7 (pH growth range of 5.0 and 8.5). Growth was inhibited by NaCl concentrations ≥1.5% (w/v), and by chloramphenicol, streptomycin, tetracycline, penicillin and ampicillin. The strain utilized fructose, mannose, glycerol, lactate, pyruvate and H2 in the presence of sulfate, and fermented pyruvate in the absence of sulfate. Strain RH04-3T reduced sulfate, sulfite, thiosulfate and elemental sulfur, but not nitrate, nitrite, iron(III), arsenate(V), vanadium(V) or cobalt(III) as terminal electron acceptors. The G + C content of DNA was 52.4 ± 0.8 mol % as determined by the thermal denaturation (Tm) method. 16S rRNA sequence analysis indicated that strain RH04-3T was a member of the genus Desulfotomaculum and was most closely related to Desulfotomaculum putei (similarity value of 95.2%) and Desulfotomaculum hydrothermale (similarity value of 93.6%). On the basis of phylogenetic and phenotypic characteristics...

Draft Genome Sequence of Fervidicella metallireducens Strain AeBT, an Iron-Reducing Thermoanaerobe from the Great Artesian Basin

Patel, Bharat K. C.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em 01/05/2014 EN
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66.42%
The genome sequence of Fervidicella metallireducens strain AeBT, a curved, heterotrophic, thermoanaerobic, and iron-reducing bacterium isolated from a gray microbial mat colonizing the free-flowing waters of a Great Artesian Basin (GAB) bore well located in outback Queensland, Australia, is reported here. The analysis of the 2.9-Mb sequence indicates that the attributes of the genome are consistent with its physiological and phenotypic traits.

Great Artesian Basin groundwater modelling

Welsh, WD; Doherty, J
Fonte: Engineers Australia Publicador: Engineers Australia
Tipo: Conference paper Formato: 329146 bytes; 359 bytes; application/pdf; application/octet-stream
EN_AU
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96.69%
This paper describes the history of groundwater modelling in the Great Artesian Basin and the challenges the data pose to groundwater modellers. Whole of basin modelling commenced in the 1970s and was taken up again in the 1990s. Improvements in computing hardware and software, data quality and hydrodynamic understanding of the Basin enabled iterative improvements in the models. Some issues persist, such as data quality and a limited understanding of the hydrogeology of the Eulo-Nebine Ridge area in southern Queensland. A method of more accurately interpolating the hydraulic head where water level measurements are decades apart is presented.; yes

A molecular systematic overview of wolf spiders associated with Great Artesian Basin springs in South Australia: evolutionary affinities and an assessment of metapopulation structure in two species

Gotch, T.; Adams, M.; Murphy, N.; Austin, A.
Fonte: C S I R O Publishing Publicador: C S I R O Publishing
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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66.57%
The molecular genetic techniques of allozyme electrophoresis and mitochondrial DNA sequencing were used to examine species boundaries, phylogenetic affinities, and population structure in wolf spiders associated with artesian springs of the Great Artesian Basin (GAB) in South Australia. These springs contain the only permanent water in this extremely arid region, and consequently are of great biological, economic, and sociological significance. Molecular diagnoses of species boundaries in nine lycosid species, involving 56 individuals genotyped at 37 putative allozyme loci and 21 individuals sequenced for a ~600-bp portion of nicotinamide adenine dinucleotide dehydrogenase 1 (NADH1), were largely concordant with those recently proposed on morphological criteria. They also identified a species not previously collected, and suggested that GAB and mesic forms of Venatrix arenaris (Hogg) may not be conspecific. As well as insights into the evolutionary relationships among species and genera, phylogenetic analysis demonstrated two distinct GAB lineages within Venatrix Roewer and Hogna Simon. Population structure analyses of the two most widespread species revealed contrasting patterns. For V. fontis Framenau & Vink, allozyme analyses of 300 individuals at 15 polymorphic loci plus NADH1 sequence analysis of 72 individuals revealed the presence of distinctive subpopulations at most sites...

A new approach to monitoring spatial distribution and dynamics of wetlands associated flows of Australian Great Artesian Basin springs using QuickBird satellite imagery

White, D.; Lewis, M.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
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96.63%
This study develops an expedient digital mapping technique using Very High Resolution satellite imagery to monitor the temporal response of permanent wetland vegetation to changes in spring flow rates from the Australian Great Artesian Basin at Dalhousie Springs Complex, South Australia. Three epochs of QuickBird satellite multispectral imagery acquired between 2006 and 2010 were analysed using the Normalised Difference Vegetation Index (NDVI). A regression of 2009 NDVI values against vegetation cover from field botanical survey plots provided a relationship of increasing NDVI with increased vegetation cover (R2 = 0.86; p < 0.001). On the basis of this relationship a vegetation threshold was determined (NDVI ≥ 0.35), which discriminated perennial and ephemeral wetland vegetation from surrounding dryland vegetation in the imagery. The extent of wetlands for the entire Dalhousie Springs Complex mapped from the imagery increased from 607 ha in December 2006 to 913 ha in May 2009 and 1285 ha in May 2010. Comparison of the three NDVI images showed considerable localised change in wetland vegetation greenness, distribution and extent in response to fires, alien vegetation removal, rainfall and fluctuations in spring flow. A strong direct relationship (R2 = 0.99; p < 0.001) was exhibited between spring flow rate and the area of associated wetland vegetation for eight individual springs. This relationship strongly infers that wetland area is an indicator of spring flow and can be used for monitoring purposes. This method has the potential to determine the sensitivity of spring wetland vegetation extent and distribution to associated changes in spring flow rates due to land management and aquifer extractions. Furthermore...

Trapped in desert springs: phylogeography of Australian desert spring snails

Murphy, N.; Breed, M.; Guzik, M.; Cooper, S.; Austin, A.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
66.42%
AIM: We investigate the phylogeographical history and determine the time-scale of population divergence of hydrobiid freshwater snails (genus Trochidrobia) inhabiting groundwater springs in the Australian desert. We test the hypothesis that divergence between geographically distinct snail populations occurred simultaneously due to their isolation in hydrologically discrete spring systems, i.e. ‘trapped in desert springs’. LOCATION: Groundwater springs of the Great Artesian Basin (GAB) in central Australia. METHODS: DNA sequence data from the mitochondrial cytochrome c oxidase subunit I gene and the nuclear 28S and internal transcribed spacer rRNA genes were used to reconstruct phylogenetic relationships within and among three species of Trochidrobia (Hydrobiidae): T. punicea (13 spring groups, n = 90), T. smithi (12 spring groups, n = 62) and T. minuta (2 spring groups, n = 4). Bayesian relaxed molecular clock analyses and approximate Bayesian computation were used to date lineage divergence and distinguish between alternative biogeographical scenarios. RESULTS: The diversification of the three Trochidrobia species probably occurred between 2.54 and 9.3 Ma, prior to the formation of the springs c. 1 Ma. Intraspecific divergences within the two widespread species occurred after the formation and colonization of the springs. Coalescent modelling and molecular clock analyses supported a simultaneous radiation of five allopatric intraspecific snail lineages within T. punicea (two lineages)and T. smithi (three lineages) across the GAB springs examined. MAIN CONCLUSIONS: The analyses support the ‘trapped in desert springs’ hypothesis for the diversification of intraspecific lineages within the species T. punicea and T. smithi. This hypothesis suggests that the formation of deserts around Lake Eyre in the early Pleistocene led to the hydrological isolation of spring complexes in the GAB...

Monitoring temporal dynamics of Great Artesian Basin wetland vegetation, Australia, using MODIS NDVI

Petus, C.; Lewis, M.; White, D.
Fonte: Elsevier BV Publicador: Elsevier BV
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.42%
Caroline Petus, Megan Lewis, Davina White

Cutting grass on desert islands: Genetic structure of disjunct coastal and central Australian populations of Gahnia trifida (Cyperaceae)

Clarke, L.; Whalen, M.; Mackay, D.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.52%
AIM Great Artesian Basin (GAB) springs in central Australia support several plant species otherwise not found in the arid zone. Evolutionary theory predicts that isolated populations will experience reductions in gene flow and genetic diversity, and higher levels of inbreeding. Our aim was to test this prediction by comparing the genetic structure of cutting grass, Gahnia trifida, (Cyperaceae) on disjunct GAB springs with coastal populations that have experienced recent fragmentation. LOCATION Naturally isolated GAB springs near Lake Eyre, central Australia, and coastal sites in southern Australia. METHODS We used 13 microsatellite markers to genotype 267 samples from six GAB spring and four coastal G. trifida populations. These data were used to estimate population genetic statistics and contemporary and historical measures of gene flow in the two regions. RESULTS GAB spring populations display lower levels of genetic diversity compared with coastal populations. Furthermore, GAB spring populations displayed much higher levels of genetic differentiation (FST = 0.52) than populations at coastal sites (FST = 0.22). Several coastal populations exhibited historical genetic connectivity, whereas analysis of molecular variation (AMOVA) and contemporary migration rate estimates indicate that populations from GAB spring groups are demographically independent. MAIN CONCLUSIONS Divergence estimates based on microsatellite data suggest restriction of central Australian G. trifida populations to refugial spring habitats since at least 15–28 ka...

Defining ecosystem processes of the Australian Great Artesian Basin springs from multi-sensor synergies

White, D.; Lewis, M.
Fonte: The Modelling and Simulation Society of Aust & NZ; Australia Publicador: The Modelling and Simulation Society of Aust & NZ; Australia
Tipo: Conference paper
Publicado em //2013 EN
Relevância na Pesquisa
66.65%
The Australian Great Artesian Basin (GAB) supports a unique and diverse range of ecologically significant groundwater-fed wetland ecosystems termed GAB springs. The springs are of great national and international importance for their ecological, scientific and economic values, and are culturally significant to indigenous Australians. The ecological sustainability of the springs has become uncertain in recent times due to increased mining operations and associated groundwater extractions from the GAB. The impacts of existing water extractions from the time of European settlement, pastoral activities and more recently mining are largely unknown. This situation is compounded by the likelihood of future increasing demand of water extractions for mining operations. The GAB springs are spatially disparate ecosystems located within the arid interior of South Australia, akin to islands in their ecological setting. The springs exhibit a diverse range of geomorphology, hydrogeology, surface expressions and vegetation community composition over a wide range of spatial scales. A suite of remote sensing technologies were used to capture the range of scales of the spring wetlands and their surface expressions. This multi-sensor approach enabled definition of the spatial and temporal responses of dominant plant species...

New insights and tools for monitoring Australian Great Artesian Basin wetlands from multi-sensor synergies

Lewis, M.; White, D.
Fonte: IEEE; Online Publicador: IEEE; Online
Tipo: Conference paper
Publicado em //2013 EN
Relevância na Pesquisa
66.42%
The Great Artesian Basin (GAB) supports a unique and diverse range of spring-fed wetland ecosystems, which are highly valued from ecological, scientific, economic and cultural perspectives. They also provide a vital source of water in the arid inland heart of Australia. In recent decades the ecological sustainability of the springs has become uncertain as demands on the GAB water resource increase. The impacts of existing and proposed future water extractions from the GAB aquifers for mining and pastoral activities are unknown. Despite the importance of the GAB springs, few of their associated wetlands have been well documented. Accurate and repeatable methods for inventory and monitoring are required for these remote and spatially dispersed groundwater-dependent ecosystems. This paper presents results from the Australian National Water Commission flagship research program, Allocating Water and Maintaining Springs in the GAB, that has developed new tools for monitoring GAB spring sensitivity to water allocations and land use [1]. We applied a range of advanced remote sensing and spatial technologies to provide new insights into the spatial distribution and variability, vegetation composition, temporal dynamics and function of groups of springs in the south-western portion of the GAB. The paper provides an evaluation of the use and suitability of data of different spatial...

Using MODIS Normalized Difference Vegetation Index to monitor seasonal and inter-annual dynamics of wetland vegetation in the Great Artesian Basin: a baseline for assessment of future changes in a unique ecosystem

Petus, C.; Lewis, M.M.; White, D.
Fonte: International Society for Photogrammetry and Remote Sensing Publicador: International Society for Photogrammetry and Remote Sensing
Tipo: Conference paper
Publicado em //2012 EN
Relevância na Pesquisa
66.77%
The Great Artesian Basin mound springs (Australia) are unique wetland ecosystems of great significance. However, these unique ecosystems are endangered by anthropogenic water extraction. Relationships have been established between the vegetated wetland area and the discharge associated with individual springs, providing a potential means of monitoring groundwater flow using measurements of wetland area. Previous studies using this relationship to monitor Great Artesian Basin springs have used aerial photography or high resolution satellite images, giving sporadic temporal information. These "snapshot " studies need to be placed within a longer and more regular context to better assess changes in response to aquifer draw-downs. In this study, the potential of medium resolution MODIS Normalized Difference Vegetation Index data for studying the long-term and high frequency temporal dynamics of wetland vegetation at the Dalhousie Spring Complex of the GAB is tested. Photosynthetic activity within Dalhousie wetlands could be differentiated from surrounding land responses. The study showed good correlation between wetland vegetated area and groundwater flow, but also the important influence of natural species phenologies, rainfall, and human activity on the observed seasonal and inter-annual vegetation dynamic. Declining trends in the extent of wetland areas were observed over the 2000– 2009 period followed by a return of wetland vegetation since 2010. This study underlined the need to continue long-term medium resolution satellite studies of the Great Artesian Basin as these data provide a good understanding of variability within the wetlands...

Mapping the wetland vegetation communities of the Australian Great Artesian Basin springs using SAM, MTMF and spectrally segmented PCA hyperspectral analyses

White, D.C.; Lewis, M.M.
Fonte: ISPRS Publicador: ISPRS
Tipo: Conference paper
Publicado em //2012 EN
Relevância na Pesquisa
66.42%
The Australian Great Artesian Basin (GAB) supports a unique and diverse range of groundwater dependent wetland ecosystems termed GAB springs. In recent decades the ecological sustainability of the springs has become uncertain as demands on this iconic groundwater resource increase. The impacts of existing water extractions for mining and pastoral activities are unknown. This situation is compounded by the likelihood of future increasing demand for extractions. Hyperspectral remote sensing provides the necessary spectral and spatial detail to discriminate wetland vegetation communities. Therefore the objectives of this paper are to discriminate the spatial extent and distribution of key spring wetland vegetation communities associated with the GAB springs evaluating three hyperspectral techniques: Spectral Angle Mapper (SAM), Mixture Tuned Matched Filtering (MTMF) and Spectrally Segmented PCA. In addition, to determine if the hyperspectral techniques developed can be applied at a number of sites representative of the range of spring formations and geomorphic settings and at two temporal intervals. Two epochs of HyMap airborne hyperspectral imagery were captured for this research in March 2009 and April 2011 at a number of sites representative of the floristic and geomorphic diversity of GAB spring groups/complexes within South Australia. Colour digital aerial photography at 30 cm GSD was acquired concurrently with the HyMap imagery. The image acquisition coincided with a field campaign of spectroradiometry measurements and a botanical survey. To identify key wavebands which have the greatest capability to discriminate vegetation communities of the GAB springs and surrounding area three hyperspectral data reduction techniques were employed: (i) Spectrally Segmented PCA (SSPCA); (ii) the Minimum Noise Transform (MNF); and (iii) the Pixel Purity Index (PPI). SSPCA was applied to NDVI-masked vegetation portions of the HyMap imagery with wavelength regions spectrally segmented for the VIS-NIR (450-1...

Electrical geophysics of carbonate mound spring complexes of the South-Western Great Artesian Basin.

Inverarity, Kent
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
96.69%
Artesian mound springs occur along the south-western edge of the Great Artesian Basin, in northern South Australia, but their underground structure and relationship to faulting is not well understood. This work aims to address this shortcoming with geophysical surveys over three mound spring systems (Beresford and Warburton Springs, the Bubbler Spring complex, and Freeling Springs), using a range of techniques: self-potential, magnetotellurics, and time-domain electromagnetics. The self-potential data contain elevated local responses to spring vents and seeps. Spatial correlation suggests that these responses are caused by flow related to springs. Similar responses also occur underneath ‘extinct’ springs, suggesting shallow subsurface discharge of aquifer water is still occurring. Little evidence was found for significant downward infiltration from spring tails. Modelling of time-domain electromagnetic and magnetotelluric data show that the confining Bulldog Shale, which is generally very conductive, contains slightly more resistive areas underneath springs and spring complexes, which may be related to a combination of carbonate buildup in the subsurface and more resistive aquifer water flowing to the surface. Magnetotelluric data and anisotropic 1D modelling suggests that fault zones exist under many of the mound springs...

Monitoring groundwater flow using electrokinetics

Lampe, R. J.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2011 EN
Relevância na Pesquisa
66.63%
Very little is known about the groundwater flow paths from the subsurface of the Great Artesian Basin to the surface basins throughout the Australian continent. The Wabma Kadarbu Mound Springs in northern South Australia lie at the south-west margin of the Great Artesian Basin and contain a number of springs that continually discharge groundwater over time. This work deals with the self potential (SP) method which was used along three intersecting lines in the area to help gain a better understanding of groundwater flow. The SP method responds to the electrokinetic phenomenon of streaming potential which can be applied to hydrogeological investigations to help evaluate the subsurface groundwater flow conditions. Because the SP data do not intrinsically yield a good indication of the depth of the sources generating groundwater flow, numerical models are developed to assess the SP distribution resulting from subsurface fluid flow. The self-potential associated with groundwater flow in an electrolytic environment is modelled by assuming a primary source as an electric double layer between the flowing groundwater and the porous media created by the flowing SP currents. This primary flow generates the secondary surface charge and double layers on the interfaces between media with different conductivities. The geometry of the sources is obtained from an image reconstruction technique which determines the spatial locations of SP sources. The modelling and image reconstructions help to obtain a better understanding of these flow paths and how they make their way to the surface can give a greater chance of collecting the groundwater to use to good effect. The results showed evidence for groundwater flow networks in the subsurface of the Wabma Kadarbu springs. The groundwater flow networks for all three lines had similar characteristics including having individual columns connected at depth and large widths for the columns. This research showed that SP can be used to help better understand groundwater flow patterns in the subsurface.; Thesis (B.Sc.(Hons)) -- University of Adelaide...

Using Spectral Induced Polarisation for water detection: an example from the Mound Springs, South Australia

Costopoulis, A.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2011 EN
Relevância na Pesquisa
66.48%
Inland Australia is characterised by low rainfall and high evaporation rates making the knowledge about the location and quality of groundwater very important. The Great Artesian Basin (GAB) covers approximately 25% of Australia, and is central Australia’s major source of groundwater, thus making it the most important source of water for this region. The springs of interest for the purpose of this study are located along the South-western margin of the basin within the Wabma Kadarbu Mound Springs Conservation Park. Our aim is to further our understanding of the spring systems within the GAB. Groundwater and near surface geophysical surveys were used to develop parameters and state variables that aid in characterising near surface groundwater systems. Most electrical geophysical surveys designed to characterise hydrological problems measure only resistivity. This study employs the complex resistivity or Spectral Induced Polarisation (SIP) method as it provides the complete set of IP and resistivity data over a large range of frequencies and is therefore considered to be an added dimension to galvanic measurements. There is a growing body of literature suggesting that the imaginary component of the IP and SIP response has a direct relationship with the hydraulic conductivity...

Independent colonization and extensive cryptic speciation of freshwater amphipods in the isolated groundwater springs of Australia's Great Artesian Basin

Murphy, N.; Adams, M.; Austin, A.
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
66.42%
The groundwater-dependent springs of the Great Artesian Basin (GAB) in arid inland Australia represent a unique and threatened ecosystem. These incredibly isolated springs support a diverse array of endemic flora and fauna. One of the common faunal groups in the GAB springs is the freshwater amphipods of the family Chiltoniidae. The morphological conservatism and taxonomic uncertainty associated with these amphipods has ensured their true biodiversity, phylogeographical history and evolutionary affinities have remained unknown. We have used mitochondrial DNA and allozyme data to unravel a complicated history of isolation, extinction and dispersal among spring amphipod populations across the GAB. The results provide evidence for multiple independent colonizations in the GAB springs, particularly within the Lake Eyre group of springs. The inclusion of a group of Western Australian (WA) stygobitic amphipods from populations up to 1500 km away found surprising evidence for a shared evolutionary history between stygobitic and GAB spring amphipods. Approximate dating of the diversity found between major clades suggests the majority of lineages originated in the late Miocene, around the time of the aridification of inland Australia. The large number of independent lineages and the close connection between GAB spring and WA stygobitic amphipods suggest that a significantly rich amphipod fauna existed in the much wetter environment that once existed in inland Australia. The results also provide evidence for a gross underestimation of the species diversity within the springs...

Luminescence dating of spring mound deposits in the southwestern Great Artesian Basin, northern South Australia

Prescott, J.; Habermehl, M.
Fonte: Taylor & Francis Ltd. Publicador: Taylor & Francis Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
96.79%
Artesian spring mound deposits in the southwestern part of the Great Artesian Basin arise from groundwater discharge from flowing springs in the southern and western margins which reaches the surface through faults and weaknesses in thin confining beds overlying the Mesozoic artesian aquifers. Carbonate in solution in the artesian groundwater is deposited by many springs as tufa, building 'spring mounds.' Active flowing and dry inactive spring mounds occur in a variety of sizes and shapes. The ages of a representative selection of spring mound deposits have been found by luminescence dating of quartz sand grains that have been incorporated in the mound deposits. The spring deposits of the active flowing springs, Big Bubbler, Blanche Cup and Beresford Spring have ages of 15.1 ± 2.2, 10.9 ± 1.5 and 13.9 ± 1.0 ka, respectively. Spring complexes with both active flowing and dry extinct mounds, Strangways and Beresford Springs, have ages of 60 ± 8 and 219 ± 35 ka, respectively. Spring deposits of springs which ceased flowing and are overlying pedestals of Cretaceous Bulldog Shale and of substantial height (up to >45 m above the surrounding plain) of Beresford Hill and Kewson Hill gave ages of 128 ± 33 ka and 400 ± 100 ka, respectively. Elizabeth Springs is a large spring mound...

Meeting the objectives? State and Territory implementation of the Great Artesian Basin Strategic Management Plan

Beven, Megan
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Relatório
Relevância na Pesquisa
96.85%
Covering one-fifth of Australia, the Great Artesian Basin (GAB) is one of the country's largest water resources. It extends across large portions of New South Wales (NSW), Queensland (QLD), the Northern Territory (NT) and South Australia (SA), and has recently been estimated to contain over 64 900 000 GL of water.1 The first artesian bore was sunk at near Bourke circa 1878. States and individuals were quick to exploit the resource with the number of bores proliferating rapidly. Outflow from the Basin peaked around 1918 at 750 000 ML per year though stabilised to around 500 000 ML per year as pressures declined and flow rate diminished.2 Though early on there was recognition of the need to manage artesian resources, governments clearly failed to prioritise and act on these concerns. This is evident in the 1990s when there were still over three thousand free flowing bores and thirty-four thousand kilometres of open bore drains in the GAB.3 Problems with surface water often overrode groundwater concerns. The ceasing of flow from fifteen hundred bores and a significant number of mound springs within the GAB provided impetus for change. In 1994 the Council of Australian Governments (COAG) undertook major reforms in groundwater management. This was followed closely by the release of the Great Artesian Basin Strategic Management Plan (GAB SMP). Released in 2000...

Sources of chloride and implications for 36Cl dating of old groundwater, southwestern Great Artesian Basin, Australia

Love, A; Herczeg, Andrew; Sampson, L; Cresswell, Richard; Fifield, L Keith
Fonte: American Geophysical Union Publicador: American Geophysical Union
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
66.63%
We investigate the relative importance of a number of processes that affect Cl and 36Cl distribution in the southwestern flow systems of the Great Artesian Basin, Australia, to provide more precise estimates of age and flow and recharge rates. In situ production of 36Cl, secular variations in the rate of production of 36Cl, and it's subsequent fallout as well as rates of diffusion of stable Cl from adjacent aquitards mask the interpretation of rates of decay of 36Cl/Cl along hydraulic gradients and can preclude estimating absolute groundwater ages. However, mean flow velocities calculated from absolute 36Cl concentrations are 0.24 ± 0.03 m/yr and are a more reliable parameter than calculated ages because fewer assumptions and approximations are required. Recharge rates to the main Cadna-owie Formation and Algebuckina Sandstone aquifer of the Great Artesian Basin estimated from Cl mass balance in the unconfined aquifers are 0.16 ± 0.08 mm/yr and were probably up to a factor of 3 higher > 30 kyr ago as indicated by decreasing Cl and δ18O concentrations along the head gradient.