Groundwater dating and residence time measurements
Production estimates for 1992 are approximately half of late 1980s peak values (AFEAS, 1993).
In research that commenced in 2007, Meredith and co-investigators have measured the isotopic signatures of groundwater and its source waters in projects in the Great Artesian Basin, Darling River Basin, Canning Basin, Perth Basin, Ti Tree Basin and other locations.This is in strong contrast to the spatially variable nature of H concentrations in rainfall.For CFCs, the atmospheric input to the ground-water can be known with a high degree of precision, even at remote sites.Determining the source of groundwater replenishment or recharge, to the aquifer, is the subject of many of Meredith’s collaborative investigations.“It is Important to understand the origin of water, where the water has been sourced from, whether it has come from a rainfall event, from surface water, such as a lake, whether it has mixed with other groundwater in a confined or unconfined system and how it is being replenished,” said Meredith.Applicants should supply (a) a curriculum vitae, including a list of publications, (b) a motivation letter including a statement of past achievement and future research interests and goals (maximum 2 pages) and (c) e-mail address of three references to: [email protected] receive full consideration, all materials must be received by .
Groundwater research at ANSTO has provided crucial information to support the management of finite groundwater resources appropriately and sustainably—answering questions about groundwater recharge, groundwater age and dynamics, the interaction between surface water and groundwater and salinisation.
It is designed to permit plotting of ages and tracer concentrations in a variety of different combinations to facilitate interpretation of measurements.
TRACERMODEL1 includes several different types of graphs that are linked to the calculations.
Excel workbooks for calculation and presentation of environmental tracer data for simple groundwater mixtures. In: IAEA Guidebook on the Use of Chlorofluocarbons in Hydrology. Atmospheric environmental tracers commonly used to date groundwater on time scales of years to decades include CFC-11, CFC-12, CFC-113, SF6, 85Kr, 3H, and 3H/3H(0), where 3H(0) refers to initial tritium (3H tritiogenic 3He) (Cook and Herczeg, 2000).
Interpretation of age from environmental tracer data may be relatively simple for a water sample with a single age, but the interpretation is more complex for a sample that is a mixture of waters of varying ages.
The ratio of isotopes for oxygen (Simplified depiction of how the source of groundwater recharge can be identified using isotopic ratios. Red line is soil water and blue line is flood water. Meredith and co-investigators have established multi-year hydrochemical databases for rainfall and riverwaters sampled from drought and flood conditions for many catchment areas in Australia.