Active-source seismic characterization of subglacial lakes: numerical modeling, field validation, and implications for Antarctic exploration

Abstract

Subglacial lakes offer unique opportunities to study ice sheet dynamics, microbial life, and climate evolution. Motivated by the upcoming seismic survey of Qilin Subglacial Lake, this study constructs a representative subglacial lake model and extends it to six geological scenarios to examine their effects on seismic wavefield characteristics, revealing the prominent occurrence of guided waves and multiple reflections. Simulated data are then analyzed to identify key imaging challenges – particularly those arising from strong multiples, low-velocity firn layers, and source-side ghosts – and to assess processing strategies, such as salt flooding, that enhance imaging accuracy and suppress noise. Commonly used seismic acquisition systems in polar regions are also reviewed to summarize their characteristics and implications for survey design. Finally, four seismic lines from Lago Subglacial CECs are processed, demonstrating strong consistency with the simulation results in terms of key seismic features, thereby validating the proposed theoretical approach. Collectively, these efforts provide a robust and broadly applicable framework for understanding seismic wave propagation in subglacial lake environments, offering both theoretical insights and methodological guidance for future Antarctic investigations.