The instrument makes use of Off-Axis integrated cavity output spectroscopy (ICOS) to simultaneously measure δ18O and δ2H stable isotopes in water samples. The Oxygen and Hydrogen stable isotope ratios can be used to study water cycles and to track water including rainwater, surface waters (rivers, ponds) and groundwater as it moves through the cycles.
The Los Gatos Research (LGR) TLWIA-45-EP is a Triple liquid water isotope analyser. It is equipped with a PAL autosampler with 162 positions and a heated vaporizer module to introduce samples into the system.
Publication links
1. De Witt M, Birkel C, Roets F, Watson A (2026). Evaluating Simulated Groundwater Contributions to Streamflow in a Data-Scarce, Semi-Arid Catchment in South Africa. Hydrogeological Processes 40: e70385. https://doi.org/10.1002/hyp.70385
2. Welham A, van Rooyen J, Watson A, Miller J, Chow R (2025). Assessing inter-basin groundwater input to the Verlorenvlei estuarine lake using stable isotopes and hydrochemistry. Journal of Hydrology: Regional Studies 57: 102081. https://doi.org/10.1016/j.ejrh.2024.102081
3. Harris C, Finlayson R, Daws W, Halenyane K, Grobbelaar C, de Roux P, Sealy J, Adams S (2025). The O-, H-, and Sr-isotope composition of Cape Town groundwater; implications for recharge and sustainability. Journal of Hydrology: Regional Studies 62: 102985. https://doi.org/10.1016/j.ejrh.2025.102985
4. de Waal J, Miller J, van Niekerk A (2023). The impact of agricultural transformation on water quality in a data-scarce, dryland landscape – a case study in the Bot River, South Africa. https://doi.org/10.1007/s10661-022-10776-4
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