Oral Presentation NCGRT/IAH Australasian Groundwater Conference 2019

Generating hydrogeological virtual realities for hypothesis testing in groundwater modelling (322)

Jeremy Bennett 1 2 , Samuel Scherrer 3
  1. Tonkin & Taylor Ltd, Newmarket, Auckland, New Zealand
  2. Centre for Applied Geosciences, University of Tübingen, Tübingen, Baden-Württemberg , Germany
  3. Institute for Modelling Hydraulic and Environmental Systems, University of Stuttgart, Stuttgart, Baden-Württemberg, Germany

Objectives

Heterogeneity of subsurface hydraulic properties controls groundwater flow and contaminant transport. However, the depositional processes which account for the creation of clastic aquifers are often neglected in hydrogeological modelling. Many existing methods for simulating subsurface heterogeneity do not honour depositional concepts, or cannot simulate heterogeneous bedding structures present in fluvial deposits.

Design and methodology

We have implemented a hierarchical modelling framework for simulating sedimentary deposits in the Hydrogeological Virtual Realities (HyVR) simulation package. The package uses an object-based modelling approach to model hydraulic parameter fields with multiple scales of heterogeneity.

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Outputs

HyVR outputs are three-dimensional parameter fields that can include hydraulic conductivity, porosity, anisotropic ratios, and bedding parameters (dip and azimuth). The last three parameters can be used to simulate hydraulic anisotropy through rotation of full hydraulic conductivity tensors. HyVR has been designed with the groundwater modeller in mind, and as such, simulation outputs can be used in forward flow-and-transport numerical modelling tools (e.g., MODFLOW), allowing qualitative geological concepts to be tested in quantitative hydrogeological models.

5d0310bd4acd4-hyvr_output.png

Conclusion

HyVR (https://github.com/driftingtides/hyvr) is an openly available Python module that is comprehensively documented (https://driftingtides.github.io/hyvr/), for ease of use. It allows hydrogeological researchers to develop object-based models for use in standard groundwater modelling software. It forms an open codebase that can be further extended and developed by the hydrogeological community.

  1. Bennett, J. P., Haslauer, C. P., Ross, M. and Cirpka, O. A. (2019), An Open, Object‐Based Framework for Generating Anisotropy in Sedimentary Subsurface Models. Groundwater, 57: 420-429. doi:10.1111/gwat.12803