Effects of Rock Glacier Dynamics on Surface Morphology and Deformation

Abstract

We apply static and kinematic geophysical measurements of rock glaciers to characterize active surface processes and to understand their effects on rock glacier dynamics. We primarily focus on the processes governing the formation of transverse ridge morphology, which include both compressional and climatic mechanisms. Supraglacial and englacial debris distribution imaged by ground-penetrating radar is examined in the context of high-resolution surface velocity measurements acquired via repeated drone photogrammetry surveys. We estimate the age of low ice accumulation periods represented by climatic ridges at Galena Creek, Wyoming, and we also observe evidence for active compressional ridge formation through a joint analysis of debris thickness distribution and surface strain. The strain analysis also has implications for mapping flow margins and regions of enhanced melt. To assist in numerical modeling of rock glacier dynamics, we explore the use of derived surface velocities and subsurface geometry products to constrain the boundary conditions and rheological parameters necessary to simulate ridge formation and assist interpretation of multidisciplinary measurements for Earth, Mars, and other planetary settings.