Earthquake-induced soil landslides: volume estimates and uncertainties with the existing scaling exponents

Quantifying landslide volumes in earthquake affected areas is critical to understand the orogenic processes and their surface effects at different spatio-temporal scales. Here, we build an accurate scaling relationship to estimate the volume of soil landslides based on 1 m pre- and post-event LiDAR elevation models. On compiling an inventory of 1719 landslides in M w 6.6 Hokkaido earthquake epicentral region, we find that the volume of soil landslides can be estimated by γ = 1.15–1.18. The total volume of eroded debris from Hokkaido catchments based on this new scaling relationship is estimated as 64–72 million m 3 . Uncertainties from the existing scaling relationships are found large except for the one found in recent literature 1 . Based on the GNSS data approximation, we noticed that the co-seismic uplift volume is smaller than the eroded volume, suggesting that frequent large earthquakes may be counterbalancing the topographic uplift through erosion by landslides.