Significant progress has been made with regard to the quantitative
integration of geophysical and hydrological data at the local scale.
However, extending the corresponding approaches to the regional scale
represents a major, and as-of-yet largely unresolved, challenge.
To address this problem, we have developed an upscaling procedure
based on a Bayesian sequential simulation approach. This method is
then applied to the stochastic integration of low-resolution, regional-scale
electrical resistivity tomography (ERT) data in combination with
high-resolution, local-scale downhole measurements of the hydraulic
and electrical conductivities. Finally, the overall viability of
this upscaling approach is tested and verified by performing and
comparing flow and transport simulation through the original and
the upscaled hydraulic conductivity fields. Our results indicate
that the proposed procedure does indeed allow for obtaining remarkably
faithful estimates of the regional-scale hydraulic conductivity structure
and correspondingly reliable predictions of the transport characteristics
over relatively long distances.