Multi-component Rayleigh wave dispersion analysis for Vs-depth profiling of Glaciers

Samara Garvey, Matthew Siegfried, Jeffrey Shragge, Lucas Zoet, Dougal Hansen, Nathan Stevens

Seismic ice velocity estimates provide quantitative constraints on glacial systems, including ice thickness, englacial structure, and bedrock topography. Velocity modeling using active-source seismic is often challenged by sub-optimal surveys due to complex field logistics. This study provides a practical guide for leveraging three-component (3-C) receivers in glacial seismic surveys to constrain potentially heterogeneous ice velocities through Rayleigh-wave dispersion analysis. We combine vertical and horizontal-radial displacement information via a complex summation in the shot-gather domain, producing a combined-complex (CC) component. The CC dispersion panels improve the low-frequency picks in the positive-frequency range, where dispersion importantly reflects progradational particle motion interacting with the ice-bedrock interface. We demonstrate the CC approach on a limited-aperture 3-C dataset collected on the Saskatchewan Glacier in the Canadian Rocky Mountains, supported by a series of synthetic studies that provide data-conditioning guidance and methodological intuition. We model Rayleigh-wave behavior in glacial stratigraphy to illustrate the sensitivities of radial displacement compared to traditional vertical-component waveforms, and to provide a general understanding of glacial-ice Rayleigh-wave behavior, which has not been fully explored in the literature. Our work thus provides practical strategies that complement CC-component dispersion analysis on glacial ice with limited geophones, enabling improved depth constraints from logistically limited surveys.