Browsing by Author "Jacobsen, GE"

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    A 1000-year isotope-based record of climate variability inferred from the sediments of Lake Yukidori, East Antarctica
    (Australasian Quaternary Association Inc., 2022-01-06) Toben, L; Rudd, R; Jacobsen, GE; Tyler, JJ
    Anthropogenic contributors to global warming are extensively altering climate and ice melt patterns in the polar regions. The Antarctic ice sheet is responsible for aspects of global climate regulation. It is vital to construct a comprehensive model of historical climate fluctuations and their consequences in the region, to effectively predict future scenarios under the current climate regime. To supplement detailed ice core records, Antarctic coastal lake sediments are a valuable paleoclimate and hydrological proxy, providing alternative indicators of environmental and climatic changes in ice-free areas. Here, we analysed a sediment core from Lake Yukidori on the Langhovde Peninsula of East Antarctica. The Yukidori sediments consist of organic rich sediments, mostly derived from aquatic mosses which grow on the lake floor. The lake itself is freely drained and freshwater, receiving water from snowmelt in a relatively small, mountainous catchment. Bulk sediment carbon and nitrogen concentration and carbon, nitrogen and oxygen stable isotope ratios were used to infer changes in lake primary productivity and the oxygen isotope composition of precipitation over the last 1000 years. The 18O/16O data exhibit marked centennial-scale variability and no marked change in the recent, post-industrial period. 15N/14N data, by contrast, suggest a notable increase in lake primary productivity in the last century, possibly a result of an increase in the seasonal ice-free period. Further work is needed to improve the chronology of the recent sediments at Lake Yukidori, and to validate these proxies in this remote environment.
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    14C activity of DIC and DOC within a clayey-silt aquitard
    (University of New South Wales and Australian Nuclear Science and Technology Organisation, 2015-07-10) Timms, W; Hartland, A; Jacobsen, GE; Cendón, DI; Crane, R; McGeeney, D
    Not provided to ANSTO Library.
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    14C AMS measurements of the bomb pulse in N- and S- hemisphere tropical trees
    (Elsevier, 1997-03-02) Murphy, JO; Lawson, EM; Fink, D; Hotchkis, MAC; Hua, Q; Jacobsen, GE; Smith, AM; Tuniz, C
    The 14C bomb-pulse signature has been measured by AMS on cross-dateable teak samples from N- and S-hemisphere locations in the tropics. Excellent agreement is found with the atmospheric 14C content in the period 1955 to 1980 for the respective hemispheres. These results demonstrate that 14C measurements can be used to facilitate growth rate determinations in tropical trees. © 1997 Elsevier B.V.
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    14C analyses at the ANTARES AMS Centre: dating the log coffins of northwest Thailand
    (Elsevier, 1994-06-03) Hotchkis, MAC; Fink, D; Jacobsen, GE; Lawson, EM; Shying, ME; Smith, AM; Tuniz, C; Barbetti, M; Grave, P; Quan, HM; Head, J
    Recent results of 14C analyses at the ANTARES AMS Centre are presented. Test measurements of 14C blanks demonstrate an ultimate sensitivity of the order of 10−15 (14C/12C ratio). Measurements of unknowns have been made with a precision in the range 1–1.5% using a “slow cycling” mode of operation where the injection magnet field is changed to inject 14C and 13C alternately. Results are presented for a series of log coffins from cave burials in NW Thailand. © 1994 Elsevier B.V.
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    14C in uranium and thorium minerals: a signature of cluster radioactivity?
    (Springer Nature, 1999-06-01) Bonetti, R; Guglielmetti, A; Poli, G; Sacchi, E; Fink, D; Hotchkis, MAC; Jacobsen, GE; Lawson, EM; Hua, Q; Smith, AM; Tuniz, C
    Various uranium and thorium minerals have been analysed with accelerator mass spectrometry to determine their 14C content. It is found that, whenever the contribution from secondary reactions such as the 11B(α,p)14C is sufficiently low, the 14C concentration is consistent with that expected from 14C (spontaneous) cluster radioactivity from radium isotopes of the uranium and thorium natural series. © Springer-Verlag 1999
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    15th International Conference on Accelerator Mass Spectrometry
    (Australian Nuclear Science and Technology Organisation, 2021-11-15) Bertuch, F; Child, DP; Fink, D; Fülöp, RH; Hotchkis, MAC; Hua, Q; Jacobsen, GE; Jenkinson, A; Levchenko, VA; Simon, KJ; Smith, AM; Wilcken, KM; Williams, AA; Williams, ML; Yang, B; Fallon, SJ; Wallner, T
    On behalf of the AMS-15 Organising committee, we would like to thank you for attending the 15th International Conference on Accelerator Mass Spectrometry. Held as an online event for the first time, the 2021 conference attracted over 300 attendees with presentations delivered by colleagues and professionals from around the globe.Applications of AMS to the world’s most pressing problems/questions: A-1 : Earth’s dynamic climate palaeoclimate studies, human impacts on climate, data for climate modelling. A-2 : Water resource sustainability groundwater dating, hydrology, water quality and management A-3 : Living landscapes soil production, carbon storage, erosion, sediment transport, geomorphology. A-4 : Catastrophic natural events volcanoes, cyclones, earthquakes, tsunamis, space weather, mass extinctions. A-5 : Advancing human health metabolic and bio-kinetic studies, bomb-pulse dating, diagnostics and bio-tracing. A-6 : Challenges of the nuclear age nuclear safeguards, nuclear forensics, nuclear waste management, nuclear site monitoring, impacts of nuclear accidents. A-7 :Understanding the human story archaeology, human evolution and migration, history, art and cultural heritage A-8 : Understanding the cosmos fundamental physics, nuclear astrophysics, nuclear physics AMS Research and Development: T-1 : Novel AMS systems, components and techniques T-2 : Suppression of isobars and other interferences T-3 : Ion sourcery T-4 : New AMS isotopes T-5 : Advances in sample preparation T-6 : Data quality and management T-7 : Facility Reports (Poster Presentation only)
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    A 7300 year record of environmental changes in a coastal wetland (Moawhitu), New Zealand, and evidence for catastrophic overwash (tsunami?)
    (Elsevier, 2020-09) Chagué, C; Cope, J; Kilroy, C; Jacobsen, GE; Zawadzki, A; Wong, HKY
    Three sedimentary sequences from a coastal wetland behind a sand barrier, on the west coast of d'Urville Island, New Zealand, were examined using a multi-proxy approach, including sedimentological, geochemical and microfossil (diatom) analyses, with the chronology established using radiocarbon and 210Pb dating. Data show that a brackish lagoon started developing 7300 year ago after formation of the sand barrier in Moawhitu. This was followed by periods of alternating wetland encroachment and open water, displaying spatial variations, until a peatland was established about 1300 cal. yr BP. The wetland was then partially drained in the early 1900s, leading to compaction of the peat near the surface. A coarse layer containing gravel, sand and shells, with a sharp lower contact, in the northern area of the wetland, is attributed to an overwash about 2500–3000 yr BP, most probably a tsunami generated by the rupture of a local or regional fault. The high-resolution continuous record obtained with XRF core scanning revealed a geochemical signature (Ca and S) for the overwash 600 m inland in the middle area of the wetland, while it was absent from the southern site 1.1 km from the shore. This suggests that, except at the northern end of Moawhitu, the sand dune acted as an effective barrier preventing any sediment from overtopping 2500–3000 yr BP, with only a geochemical evidence marking the extent of seawater inundation. No sedimentological or geochemical evidence could be found in the wetland for the 15th century tsunami that had destroyed almost an entire community in Moawhitu, as recounted in Māori oral tradition (pūrākau), although pebbles at the surface of the dune are likely to be linked to this event. Thus, the sand dune appears to have again acted as an effective barrier for the overwash in the 15th century. However, our study suggests that the area might have been impacted by more than one tsunami in the last 3000 years. It also shows that a high-resolution continuous XRF record can provide the evidence for short-term changes (catastrophic or not) that did not leave any clear sedimentological signature, thus providing a better insight of environmental changes in any depositional environment. © 2020 Elsevier B.V
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    9th millennium plant subsistence in the central Anatolian highlands: new evidence from Pınarbaşı, Karaman Province, central Anatolia
    (Elsevier, 2014-01) Fairbairn, AS; Jenkins, E; Baird, D; Jacobsen, GE
    Plant macrofossil analysis, phytolith analysis and AMS radiocarbon dating at Pinarbaşi in central Anatolia confirm the presence and continuity of plant gathering practice as a key subsistence strategy from c. 9000-7700cal BC. Results demonstrate the use of almond, terebinth and hackberry as food plants, similar to Palaeolithic/Epipalaeolithic subsistence strategies in the Antalya region. Crop and/or crop progenitor use is unsupported, with sporadic cereal macrofossils rare and shown by direct radiocarbon dating to be intrusive, a conclusion supported by the phytolith analysis. Seed exploitation is also rejected. Results confirm the presence of sedentary foragers from 9000cal BC in central Anatolia, contemporary with the Levantine PPNA-Early PPNB, suggest a different plant subsistence focus to contemporary forager societies in the Fertile Crescent and indicate economic differences with contemporary sites in central Anatolia which were already cultivating crops. © 2013 Elsevier Ltd.
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    AMS at ANTARES – the first 10 years
    (Elsevier, 2000-10) Lawson, EM; Elliott, G; Fallon, J; Fink, D; Hotchkis, MAC; Hua, Q; Jacobsen, GE; Lee, P; Smith, AM; Tuniz, C; Zoppi, U
    The status and capabilities of the ANTARES AMS facility after 10 years are reviewed. The common AMS radioisotopes, 10Be, 14C, 26A1, 36C1 and 129I, are routinely analysed. A capability for the detection of 236U and other actinide isotopes has been developed. The measurement program includes support to Quaternary science projects at Australian universities and to ANSTO projects in global climate change and nuclear safeguards. © 2000 Elsevier Science B.V.
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    AMS C14 dating using pollen concentrate for sediments with low organic content in the tropics of Australia
    (Elsevier, 2007-07) Moss, PT; McTainsh, GH; Dunbar, GB; Dickens, G; Jacobsen, GE
    This study discusses the results of using pollen concentrate for AMS C14 dating of sediments with low organic content for two sites in the tropical north of Australia. The first site from the Mitchell Plateau in the Kimberly region of Western Australia is a swamp deposit within a small enclosed drainage basin, with a high content of inorganic sediments. Seven AMS C-14 dates have been obtained for the first 70 cm of this record, which provides a relatively consistent age chronology that stretches back 1670 BP and can be directly compared with pollen data from the same depths. The second site, ODP 820, from the humid tropics region of northeastern Queensland consists of marine sediments with high values of Calcium Carbonate. Several AMS C-14 on foraminifera have been obtained for this record, which provide a consistent age chronology for the first 8 m of the core and which is thought to cover the last 44,000 BP. More recently, seven AMS C-14 dates based on pollen concentrate have been obtained and have been directly compared with the forminiferal derived ages, as well as the core’s pollen record. The dates and concurrent pollen data provide a better understanding of the sedimentological processes, both marine and terrestrial, that have been operating in the region, as well as providing insight into the nature of the reworking of pollen grains in marine sediments.
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    AMS measurement of 129I, 36C1 and 14C in underground waters from Mururoa and Fangataufa atolls
    (Elsevier, 2000-10) Jacobsen, GE; Hotchkis, MAC; Fink, D; Child, DP; Tuniz, C; Sacchi, E; Levins, DM; Povinec, PP; Mulsow, S
    AMS analyses of 36Cl, 129I and 14C in underground water have been performed as part of IAEA’s assessment of the radiological situation at Mururoa and Fangataufa atolls. The samples consisted of waters from monitoring wells, and from two cavity-chimneys created by underground nuclear tests. The water samples from the monitoring wells contained varying concentrations of radionuclides, with the highest concentrations of radionuclides found in the two test cavity-chimneys. A comparison of the concentrations of radionuclides determined by AMS, 36Cl and 129I, and with radionuclides determined using conventional methods, 3H, 90Sr and 137Cs, shows a reasonable correlation. However, some differences in behaviour, mainly attributed to differences in the sorption characteristics of the elements, are discernible. The concentrations of radionuclides in the underground environment were used to validate geosphere transport models. © 2000 Elsevier Science B.V.
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    AMS radiocarbon analysis of microsamples
    (Australian Institute of Nuclear Science and Engineering, Australian Nuclear Science & Technology Organisation and Australian Museum, 1997-02-12) Jacobsen, GE; Hua, Q; Tarshishi, J; Fink, D; Hotchkis, MAC; Lawson, EM; Smith, AM; Tuniz, C
    The ANTARES AMS Centre has two chemistry laboratories dedicated to preparing targets for measurement. Target preparation encompasses a variety of activities ranging from the curation of incoming samples to the numerous steps involved in the purification and processing of dissimilar samples. One of the two laboratories is set up for the physical and chemical pretreatment of 14C samples. Treatments include cleaning by sonification, sorting, grinding and sieving, and chemical treatments such as the standard AAA treatment, and solvent extraction. Combustion and graphitisation are also carried out in this laboratory. The second laboratory is a clean room and is dedicated to the combustion, hydrolysis and graphitisation of 14C samples as well as processing targets for the other isotopes. Combustion is achieved by heating the sample to 900 deg C in the presence of CuO, the resulting gas is purified by passing over Ag and Cu wire at 600 deg C. Graphitisation is carried out by reducing the CO{sub 2} with an iron catalyst (600 deg C) in the presence of zinc (400 deg C) and a small amount of hydrogen. Samples such as charcoal, shell, bone, wood, sediment, seawater and groundwater, containing 0.3-1 mg or more of original carbon, are processed routinely for radiocarbon analysis. The current 14C chemistry background for 1 mg carbon is approx. 0.3 percent of modern carbon (pMC) enabling materials` dating up to 45 000 BP.
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    ANSTO AMS facility sample processing and target preparation: an update
    (20th International Radiocarbon Conference, 2009-06-01) Jacobsen, GE; Barry, LA; Bertuch, F; Hua, Q; Mifsud, C; Pratap, P; Reilly, N; Varley, S; Williams, AG
    The ANSTO AMS Facility has been operating for the past 17 years, and comprises two accelerators complemented with a suite of chemistry laboratories dedicated to the processing of samples for carbon, beryllium, aluminium, iodine, and actinide analyses. The facility performs and supports a wide range of research in the areas of paleoclimate change, water resource sustainability, archaeology, geomorphology, and nuclear safeguards. As a result, the chemistry laboratories are called upon to process a large variety of sample types and increasing numbers of samples. The radiocarbon laboratories process charcoal, wood, sediments, pollen, carbonates, waters, textiles, and bone though the pretreatment stages, combustion or hydrolysis, and graphitization. Over the years, we have continually worked to improve pretreatment methods, reduce sample size, and reduce background. Construction of a dedicated low-background combustion and graphitization system is underway. The cosmogenic laboratories process quartz-bearing rocks and sediments through cleaning, dissolution, separation, and purification of Be and Al and preparation of targets as oxides. In this poster, we will summarize the current methods and developments in the radiocarbon and cosmogenic chemistry laboratories.
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    ANSTO Radiocarbon Laboratory: developments to meet the needs of our community
    (Australian Nuclear Science and Technology Organisation, 2021-11-17) Bertuch, F; Williams, AA; Yang, B; Nguyen, TH; Varley, S; Jacobsen, GE; Hua, Q
    The radiocarbon chemistry laboratories in the Centre for Accelerator Science at the Australian Nuclear Science and Technology Organisation (ANSTO) have a role providing support to AMS measurements for government organisations, industry, and academia in Australia and overseas. Over recent years the radiocarbon laboratories at ANSTO have expanded to support projects that address unique challenges which include environmental issues, the sustainable management of water resources, climate variability, ecological studies, and research into Indigenous heritage. The increase of work in these areas has seen a growing demand for processing samples of groundwater, rock art, ice cores, tree rings and Antarctic mosses. Here we will present an update of our procedures for processing a diverse range of sample types. We will also describe developments such as an automated dissolved organic carbon (DIC) extraction system for water samples, and our automated AAA pretreatment system. We will also outline our range of graphitisation systems which include a set of 24 Fe/H2 graphitisation units, 6 microconventional furnace (MCF) Fe/H2 graphitisation lines, a laser heated furnace (LHF) graphitisation system, and an Ionplus AGE-3 graphitisation system (owned by UNSW). Our MCF and conventional graphitisation lines have been designed to handle and reliably produce graphite targets containing as little as 5 μg and 10ugC of carbon respectively), making the graphitisation of minute carbon samples from rock art and ice cores possible.
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    The ANTARES AMS Centre : a status report
    (Cambridge University Press, 2016-07-18) Tuniz, C; Fink, D; Hotchkis, MAC; Jacobsen, GE; Lawson, EM; Smith, AM; Hua, Q; Drewer, P; Lee, P; Levchenko, VA; Bird, R; Boldeman, JW; Barbetti, M; Taylor, G; Head, J
    The ANTARES accelerator mass spectrometry facility at Lucas Heights Research Laboratory is operational and AMS measurements of 14C, 26Al and 36Cl are being carried out routinely. Measurement of 129I recently commenced and capabilities for other long-lived radioisotopes such as 10Be are being established. The overall aim of the facility is to develop advanced programs in Quaternary science, global climate change, biomedicine and nuclear safeguards. © the Department of Geosciences, The University of Arizona
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    The ANTARES AMS Centre at the Lucas Heights Research Laboratories
    (Elsevier, 1994-06-03) Tuniz, C; Fink, D; Hotchkis, MAC; Jacobsen, GE; Lawson, EM; Smith, AM; Bird, JR; Boldeman, JW
    The ANTARES AMS facility at the Lucas Heights Research Laboratories is operational and AMS measurements of 14C and 26Al are performed routinely. Measurement programs for a variety of other long-lived cosmogenic radioisotopes are being implemented on specialised beamlines. The overall aim of the facility is to establish an AMS centre for advanced studies in global change and Quaternary science. Other projects in biomedicine and nuclear safeguards monitoring are also being developed. © 1994 Elsevier B.V.
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    The ANTARES AMS facility at ANSTO
    (Elsevier, 2004-08) Fink, D; Hotchkis, MAC; Hua, Q; Jacobsen, GE; Smith, AM; Zoppi, U; Child, DP; Mifsud, C; van der Gaast, H; Williams, A; Williams, M
    This paper presents an overview of ANTARES operations, describing (1) technical upgrades that now allow routine 0.3–0.4% 14C precision for 1 mg carbon samples and 1% precision for 100 micrograms, (2) proficiency at 236U measurements in environmental samples, (3) new developments in AMS of platinum group elements and (4), some major application projects undertaken over the period of the past three years. Importantly, the facility is poised to enter into a new phase of expansion with the recent delivery of a 2 MV 14C tandem accelerator system from High Voltage Engineering (HVE) and a stable isotope ratio mass spectrometer from Micromass Inc. for combustion of organic samples and isotopic analysis. © 2004 Elsevier B.V.
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    Application of environmental isotopes of hydrogen (3H), Carbon (13C & 14C) and oxygen (16O/18O) in studies of groundwater-streamflow interactions
    (International Atomic Energy Agency, 2006) Stone, DJM; Jacobsen, GE; Hughes, CE; Szymczak, R
    A current major effort in Australian water management is the conjunctive management of hydraulically connected Groundwater and Surface water systems, to provide the maximum benefit to water stakeholders. In particular Australia has a legislative limit on the amount of surface water that can be utilised in a particular catchment, but that is not the case for Groundwater, leading to tension amongst users in connected systems. Valley and Murray-Darling Basin, NSW. Streamflow was sampled using a plastic bailer while groundwaters were withdrawn with the use of a Grundfos MP1 environmental sampling pump. They were analysed for stable isotopes ({sup 2}H/H, {sup 18}O/{sup 16}O) ratios, tritium ({sup 3}H), radiocarbon ({sup 14}C) and major and minor chemical species. Rainwaters were collected and analysed for stable isotopes only. Previous tritium in precipitation data were also utilised. Ion Chromatography was used for the analysis of the anions while either ICP-MS or ICP-AES was used for cations. The tritium analysis was carried out by standard procedures of electrolytic concentration and liquid scintillation counting. Analysis of the water samples for deuterium was conducted by CSIRO, Isotope Analysis laboratory using the zinc reduction method and a VG Isogas mass spectrometer (error; {+-} 0.8 per mille). Radiocarbon in groundwaters are measured using accelerator mass spectrometry (AMS). The water samples are filtered to 45 {mu}m prior to CO{sub 2} collection. Dissolved inorganic carbon (DIC) is separated by acidifying the water samples with 85% phosphoric acid, the resulting CO{sub 2} is collected by sparging with He for 15 mins and cryogenic trapping. The CO{sub 2} is purified by heating overnight to 600 deg. C in the presence of Ag wire. Graphite targets are then prepared by the reduction of the CO{sub 2} using H{sub 2} with an Fe catalyst at 600 deg. C. The resulting graphite/iron mix is measured in the ANTARES 10MV Tandem Accelerator. The determination of oxygen-18 was conducted at the University of Wollongong using the CO{sub 2} gas equilibration method, purified using a Micromass Multiprep Unit and measured on a Micromass Prism III (error; {+-} 0.1 per mille). A plot of tritium activity versus borehole location and depth, indicates that the Brogo River (Bega Valley, NSW) is not recharging the adjacent alluvium since the tritium is much lower than in the streamwater. The Bega river however is recharging the adjacent alluvium, both above and below its confluence with the Brogo river, since tritium values are similar in stream and alluvium. Isotopes such as the stable and radioactive isotopes of water and carbon are particularly appropriate for the study of these connected water systems, providing a clear method of determining the source of groundwater, and hence the extent of mixing of nearby surface water (such as the local river), and the time frame for the mixing process. In particular the stable isotopes 2-H, 18-O, and 13-C provide a robust end-member analysis for the hydrographic separation of regional groundwater and any amount of river water which was replenished at a remote location; while the radioactive isotopes 3-H and 14-C are used to confirm the presence in groundwater of (isotopically modern) surface water, but also accurately determine the apparent rate of mixing at particular distances from the river. © The Authors
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    Application of environmental isotopes of hydrogen (3H), Carbon (13C & 14C) and oxygen (16O/18O) in studies of groundwater-streamflow interactions
    (International Atomic Energy Agency, 2004-10-25) Stone, DJM; Jacobsen, GE; Hughes, CE; Szymczak, R
    A current major effort in Australian water management is the conjunctive management of hydraulically connected Groundwater and Surface water systems, to provide the maximum benefit to water stakeholders. In particular Australia has a legislative limit on the amount of surface water that can be utilised in a particular catchment, but that is not the case for Groundwater, leading to tension amongst users in connected systems. Valley and Murray-Darling Basin, NSW. Streamflow was sampled using a plastic bailer while groundwaters were withdrawn with the use of a Grundfos MP1 environmental sampling pump. They were analysed for stable isotopes ({sup 2}H/H, {sup 18}O/{sup 16}O) ratios, tritium ({sup 3}H), radiocarbon ({sup 14}C) and major and minor chemical species. Rainwaters were collected and analysed for stable isotopes only. Previous tritium in precipitation data were also utilised. Ion Chromatography was used for the analysis of the anions while either ICP-MS or ICP-AES was used for cations. The tritium analysis was carried out by standard procedures of electrolytic concentration and liquid scintillation counting. Analysis of the water samples for deuterium was conducted by CSIRO, Isotope Analysis laboratory using the zinc reduction method and a VG Isogas mass spectrometer (error; {+-} 0.8 per mille). Radiocarbon in groundwaters are measured using accelerator mass spectrometry (AMS). The water samples are filtered to 45 {mu}m prior to CO{sub 2} collection. Dissolved inorganic carbon (DIC) is separated by acidifying the water samples with 85% phosphoric acid, the resulting CO{sub 2} is collected by sparging with He for 15 mins and cryogenic trapping. The CO{sub 2} is purified by heating overnight to 600 deg. C in the presence of Ag wire. Graphite targets are then prepared by the reduction of the CO{sub 2} using H{sub 2} with an Fe catalyst at 600 deg. C. The resulting graphite/iron mix is measured in the ANTARES 10MV Tandem Accelerator. The determination of oxygen-18 was conducted at the University of Wollongong using the CO{sub 2} gas equilibration method, purified using a Micromass Multiprep Unit and measured on a Micromass Prism III (error; {+-} 0.1 per mille). A plot of tritium activity versus borehole location and depth, indicates that the Brogo River (Bega Valley, NSW) is not recharging the adjacent alluvium since the tritium is much lower than in the streamwater. The Bega river however is recharging the adjacent alluvium, both above and below its confluence with the Brogo river, since tritium values are similar in stream and alluvium. Isotopes such as the stable and radioactive isotopes of water and carbon are particularly appropriate for the study of these connected water systems, providing a clear method of determining the source of groundwater, and hence the extent of mixing of nearby surface water (such as the local river), and the time frame for the mixing process. In particular the stable isotopes 2-H, 18-O, and 13-C provide a robust end-member analysis for the hydrographic separation of regional groundwater and any amount of river water which was replenished at a remote location; while the radioactive isotopes 3-H and 14-C are used to confirm the presence in groundwater of (isotopically modern) surface water, but also accurately determine the apparent rate of mixing at particular distances from the river. © The Authors
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    Application of environmental isotopes to study aquifer interactions and their impact on groundwater salinisation in western Victoria
    (Australian Institute of Nuclear Science and Engineering (AINSE), 2007-11) Raiber, M; Webb, JA; Jacobsen, GE; Chisari, R; Williams, AA; Neklapilova, B