Noble gas isotope facility for groundwater studies
We use high-resolution measurement of all stable noble gases and tritium via helium-3 ingrowth to understand groundwater systems and processes
To secure our groundwater for future generations and the environment we need better understanding of the limits of this resource and potential risks from new industries, climate change, and underground waste disposal (CO2, chemical and radioactive waste). Communities, industries, and governments need confidence that developments and management actions will avoid undue ecosystem disruption and be able to sustain existing industries that have developed around groundwater resources.
Groundwater dependent ecosystems associated with springs provide habitats for vulnerable species such as native tree frogs as seen here near Hot Spring Valley, Northern Territory Credit: Punjehl Crane, CSIRO.
Noble gas isotopes are so-called environmental tracers: chemical substances that exist within the natural environment, either produced naturally from rocks or in the atmosphere. Infiltration of rainwater-containing isotopes generates a signal that can be traced to reveal among other things origin of groundwater and its velocity. Studying many different tracers all at once has significant advantages over using only single tracers, as this gives greater confidence about where and how groundwater recharges, how different aquifers are connected and how they feed surface water, springs and groundwater dependent ecosystems.
Our tracer-based research played a key role in improving the understanding of groundwater systems with more robust conceptual models. Some environmental tracers (such as 2H, 3H, 18O, 13C, 14C, 36Cl) are routine tools that have been used for decades in groundwater science. More recently noble gases (helium, neon, argon, krypton, and xenon) and its isotopes have become available as a very reliable and versatile tool to complement the above traditional tracers.
