Don’t Use Geophysics

Abstract:

Geophysical methods and, in particular, approaches for integrating geophysical methods into hydrologic investigations, have advanced rapidly over the last decade. Some methods (e.g. TDR) have become standard, off-the-shelf, components of hydrogeologic field studies. Others (e.g. GPR, TEM, and ERT) are being used widely in reconnaissance-level studies. There is also increasing appreciation of the advantages available through leveraging multiple geophysical methods and standard hydrogeologic measurements and through joint and coupled hydrogeophysical inversion. However, to date, there have been very few efforts to develop approaches to determine which geophysical methods (if any) may be suitable for a given hydrologic investigation and even fewer attempts to optimize the integration of geophysics. I will discuss why coupled hydrogeophysical analysis should form the basis for developing logical, quantitative approaches to the design of hydrogeophysical investigations. I will also suggest that if you cannot justify the use of geophysics for a hydrologic investigation, you should not use geophysics.