At the largest scale, hydraulic conductivities are typically derived through inverse modelling involving matching groundwater flow model outputs to observation data, such as hydraulic heads (Laloy et al., 2013). At the next largest scale, pump tests may be applied (Bredehoeft et al., 1983). At the next scale, hydraulic conductivity may be derived from slug tests, single well tests with packers or drill stem tests (QWC, 2012). Core-scale measurements are typically used at the centimetre to decimetre scale (QGC, 2013). For micro- or even nano-meter scale hydraulic conductivities pore-scale modelling can be applied based on reconstructed 3-D pore models derived from micro-computed tomography images (Gerke et al., 2013). Methods for obtaining hydraulic properties are summarised in Table 3. Hydraulic property observations are summarised in terms of increasing measurement scale, ranging from core scale to regional scale. A detailed discussion of the main three observation/measurement scales is provided in Sections 3.1.1 to 3.1.3 . Table 3. Summary of methods available for the measurement of hydraulic parameters. Method type Test method Measurement Observation Derived property Hydraulic, Constant head Core-scale. Point values Flux Hydraulic laboratory conducted on small conductivity Triaxial cell Flux samples, often collected Centrifuge Flux during drilling Gas Flux Air permeameter Pressure modelling based on Core-scale Porosity micro-CT images or mercury porosimetry Hydraulic, Single well Slug test Bore-scale. Near the Pressure Hydraulic based borehole; intervals when conductivity using packers Drill stem test Bore-scale. Near the Pressure Hydraulic borehole; intervals when conductivity, using packers storage Flow meters Bore-scale Heat flux, EM Hydraulic current, conductivity acoustic Pump test Bore-scale. Larger than Pressure Hydraulic the borehole; intervals conductivity when using packers Multiple wells Averaged Pressure Hydraulic over a large aquifer conductivity, volume, identify storage anisotropy Passive test Averaged Pressure Hydraulic over entire aquitard conductivity Time series analysis Bore-scale. Averaged Pressure Hydraulic over entire aquitard conductivity Geophysical ray, neutron density, Near the Porosity Hydraulic and/or sonic logs borehole conductivity
At the largest scale, hydraulic conductivities are typically derived through inverse modelling involving matching groundwater flow model outputs to observation data, such as hydraulic heads (Laloy et al., 2013). At the next largest scale, pump tests may be applied (Bredehoeft et al., 1983). At the next scale, hydraulic conductivity may be derived from slug tests, single well tests with packers or drill stem tests (QWC, 2012). Core-scale measurements are typically used at the centimetre to decimetre scale (QGC, 2013). For micro- or even nano-meter scale hydraulic conductivities pore-scale modelling can be applied based on reconstructed 3-D pore models derived from micro-computed tomography images (Gerke et al., 2013). Methods for obtaining hydraulic properties are summarised in Table 3. Hydraulic property observations are summarised in terms of increasing measurement scale, ranging from core scale to regional scale. A detailed discussion of the main three observation/measurement scales is provided in Sections 3.1.1 to 3.1.3 . Table 3. Summary of methods available for the measurement of hydraulic parameters. Method type Test method Measurement Observation Derived property Hydraulic, laboratory Constant head Core-scale. Point values conducted on small samples, often collected during drilling Flux Hydraulic conductivity Triaxial cell Flux Centrifuge Flux Gas Flux Air permeameter Pressure modelling based on micro-CT images or mercury porosimetry Core-scale Porosity Hydraulic, based Single well Slug test Bore-scale. Near the borehole; intervals when using packers Pressure Hydraulic conductivity Drill stem test Bore-scale. Near the borehole; intervals when using packers Pressure Hydraulic conductivity, storage Flow meters Bore-scale Heat flux, EM current, acoustic Hydraulic conductivity Pump test Bore-scale. Larger than the borehole; intervals when using packers Pressure Hydraulic conductivity Multiple wells Averaged over a large aquifer volume, identify anisotropy Pressure Hydraulic conductivity, storage Passive test Averaged over entire aquitard Pressure Hydraulic conductivity Time series analysis Bore-scale. Averaged over entire aquitard Pressure Hydraulic conductivity Geophysical ray, neutron density, and/or sonic logs Near the borehole Porosity Hydraulic conductivity
overview-aquitard-and-geological-fault-simulation-approaches.docx