Estimating Groundwater System Properties from Standard Monitoring Datasets
Presenter: Dr Gabriel C Rau
When: Tuesday 12th December, 17:30 for a 18:00 start
Where: Level 27, 680 George Street, Sydney
Online: To be supplied closer to the date
Characterising subsurface hydraulic and geomechanical properties is vital for effective Earth resource management. Traditional methods, such as hydraulic and geotechnical testing, are costly and necessitate specialized infrastructure, thereby restricting their broad adoption. In contrast, leveraging the groundwater response to natural forces, such as Earth tides and atmospheric pressure variations, offers an innovative means to assess confinement and estimate hydro-geomechanical properties in-situ. This approach, known as Passive Subsurface Characterisation (PSC), proves cost-effective and versatile when applied to monitoring datasets from boreholes across diverse geographical locations. It facilitates cost-effective estimation of fundamental hydraulic properties, e.g., hydraulic conductivity, specific storage, barometric efficiency, as well as poroelastic parameters, e.g., porosity, shear modulus, Young’s modulus, bulk modulus, Skempton’s and Biot-Willis coefficients, and undrained/drained Poisson’s ratios. PSC relies on standard but high-resolution measurements of groundwater hydraulic head, barometric pressure, and theoretically calculable Earth tides. To bridge the gap between scientific research and practical application, a Python package called HydroGeoSines (HGS) has been developed. HGS incorporates key methodologies from peer-reviewed literature, empowering individuals with Python proficiency to apply PSC to their own datasets. Selected workflows are also made accessible through a browser-based calculator under https://groundwater.app. This presentation seeks to increase awareness of the underutilised potential of PSC while advocating for the evolution of groundwater monitoring practices to maximise the benefits offered by this innovative approach.
Figure from: McMillan, T. C., Rau, G. C., Timms, W. A., & Andersen, M. S. (2019). Utilizing the impact of Earth and atmospheric tides on groundwater systems: A review reveals the future potential. Reviews of Geophysics, 57. https://doi.org/10.1029/2018RG000630
Dr. Gabriel Rau is a passionate geo-environmental scientist and engineer committed to advancing our understanding of groundwater resources to promote sustainable Earth resource management. He earned his PhD in Hydrogeology in 2012 from UNSW Sydney (Australia) after a MSc in Environmental Engineering Science in 2008 from the Uni of Stuttgart (Germany). In 2023, Gabriel achieved a Habilitation, the German professorial qualification, in Applied Geosciences. Gabriel’s career has been marked by his contributions working internationally at institutions such as UNSW Sydney (Australia) and the Karlsruhe Institute of Technology (KIT) in Germany. His professional journey has been characterised by hands-on laboratory and fieldwork, the design of specialised experiments, and the application of data science tools, notably Python, to unravel the intricacies of subsurface properties and processes. Since 2022, he serves as a Lecturer in Hydrogeology at the University of Newcastle (UON), where he continues to lead collaborative projects that transcend borders and disciplines, contributing to a deeper understanding of groundwater resources.