Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

The use of airborne electromagnetics (AEM) for hydrogeological investigations often requires high resolution data. Optimisation of AEM data therefore requires careful consideration of AEM system suitability, calibration, validation and inversion methods. In the Broken Hill managed Aquifer Recharge (BHMAR) project, the helicopter-borne SkyTEM transient EM system was selected after forward modelling of system responses and assessment of test line data over potential targets. The survey involved acquisition of 31,834 line km of data over an area of 7,500 km2 of the River Darling Floodplain. Initial FAI inversions provided within 48 hours of acquisition were used to target 100 sonic and rotary mud holes for calibration and validation. A number of different (Laterally and Spatially Constrained) inversions of the AEM data were carried out, with refinements made as additional information on vertical and lateral constraints became available. Finally, a Wave Number Domain Approximate Inversion procedure with a 1D multi-layer model and constraints in 3D (including boreholes), was used to produce a 3D conductivity model. This inversion procedure only takes days to run, enabling rapid trialling to select the most appropriate vertical and horizontal constraints. Using this approach has produced reliable, quantitative estimates of the 3D conductivity structure, and enabled identification of a diverse range of MAR options and groundwater resources. The hydrogeological complexity revealed by AEM mapping greatly improves the parameterisation of groundwater models, and provides a framework for understanding complex hydrogeological and hydrogeochemical processes that are critical to assessment of a range of MAR, surface water and groundwater extraction options.

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available