Slope failure remediation using constrained horizontal-to-vertical spectral ratio inversion techniques

Slope failure rates may be exacerbated by increased precipitation patterns associated with climate change. Such events are extremely disruptive for local communities affected. Rapid engineering remediation solutions generally require immediate site characterization, including information on depth to intact bedrock and groundwater conditions – often on dangerous or still-failing slopes. Horizontal-to-vertical spectral ratio is a low-impact technique capable of rapidly providing key information on the subsurface. Here we develop a robust workflow for constrained minimization of horizontal-to-vertical spectral ratio data and develop constrained horizontal-to-vertical spectral ratio profiling methodologies. We present results from a number of landslide sites in eastern Australia and demonstrate the utility of horizontal-to-vertical spectral ratio in delineating both fractured-rock aquifers at high-risk sites and colluvium–bedrock contact on active landslide sites, where traditional seismic methods were not practical.