Quantifying the Hydrologic Effects of the 2010-2011 Canterbury Earthquakes

Abstract:

The 2010-2011 Canterbury sequence earthquakes around Christchurch, New Zealand, directly impacted systems from infrastructure to ground structure, but of particular importance to the local population is the hydrologic response of the aquifers and shallow subsurface. While co-seismic and post-seismic responses to the three major earthquakes have been extrapolated from temporally correlated well data, here we develop a numerical model to reconstruct the aquifers’ response to each earthquake. By using fault slip distributions modeled from InSAR data, we can project the effects of slip on the fault to monitored well sites around the Canterbury region, ultimately extrapolating the stress regimes at these adjacent localities. Furthermore, our model will enable us to extract the specific responses of the hydrologic systems to both the co-seismic and post-seismic effects of the earthquakes. With this model we hope to gain a more comprehensive understanding of aquifer behavior, localized liquefaction, and surface deformation in relation to this devastating series of earthquakes.