Integrated geophysical imaging of permafrost distribution across an Arctic watershed

Abstract

Arctic systems are changing rapidly, yet data characterizing the thermohydrological conditions of these systems are rare. We apply a recently developed petrophysical joint inversion approach to seismic refraction and electrical resistivity tomography data to estimate the rock, ice, water, and air content throughout a watershed on the Seward Peninsula, Alaska. Our results show thate single geophysical techniques fail in imaging the base of permafrost, while the results of the petrophysical joint inversion provide an estimate of this interface, as well as a refined imaging of soil and permafrost properties. While our results are in agreement with surface observations and shallow soil temperature and moisture measurements, deep borehole data confirming our results are still missing. Nevertheless, this approach provides a means to overcome inherent limitations of Arctic research by enabling imaging the base of permafrost.