EGU23-8113
https://doi.org/10.5194/egusphere-egu23-8113
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Estimating correlation lengths of aquitard hydraulic conductivity by inverse geostatistical modelling of a pumping test

Martijn van Leer1, Willem Jan Zaadnoordijk2,3, Alraune Zech4, Jasper Griffioen2,5, and Marc Bierkens1,6
Martijn van Leer et al.
  • 1Department of Physical Geography, Utrecht University, Utrecht, Netherlands (m.d.vanleer@uu.nl)
  • 2TNO- Geological Survey of the Netherlands, Utrecht, Netherlands
  • 3Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands
  • 4Department of Earth Sciences, Utrecht University, Utrecht, Netherlands
  • 5Copernicus Institute of Sustainable Development, Utrecht University, Utrecht
  • 6Unit Subsurface and Groundwater Systems, Deltares, Utrecht

Aquitards are common hydrogeological features in the subsurface and its properties are important for e.g. water resource management, subsidence, contamination transport and aquifer thermal energy storage. Typically pumping test are used to parameterize the hydraulic conductivity of aquitards. However, with analytical interpretation of pumping tests it is difficult to take spatial variability and uncertainty into account. Alternatively, core-scale measurements of hydraulic conductivity are used in geostatistical upscaling methods, for which their correlation lengths are needed. However, this information is extremely difficult to obtain. In this study we investigate whether a pumping test can be used to obtain the correlation lengths needed for geostatistical upscaling and  account for the uncertainty about heterogeneous aquitard conductivity. We generated random realizations from core scale data with varying correlation lengths and inserted these into a groundwater flow model which simulates the outcome of an actual pumping test. We selected the realizations which yielded a better fit to the pumping test data than the traditional pumping test result assuming homogeneous layers. Ranges of horizontal and vertical correlation lengths that fit the pumping test well are found. However, considerable uncertainty regarding the correlation lengths remains which should be considered when parameterizing a regional groundwater flow model.

How to cite: van Leer, M., Zaadnoordijk, W. J., Zech, A., Griffioen, J., and Bierkens, M.: Estimating correlation lengths of aquitard hydraulic conductivity by inverse geostatistical modelling of a pumping test, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-8113, https://doi.org/10.5194/egusphere-egu23-8113, 2023.