Overview

• The study published on October 8, 2025 in Geophysical Research Letters concludes that CO2-ice blocks sliding or burrowing downslope excavate sand through explosive sublimation.
• In The Open University's Mars chamber, researchers set CO2-ice blocks on sandy slopes under Martian pressure and reproduced deep, sinuous channels with flanking ridges.
• Orbital images of dune fields, including Russell and Matara craters and sites in Hellas Planitia and Galle crater, show seasonal activity that matches the lab-generated features.
• Winter lays down up to roughly 70 centimeters of CO2 frost on mid‑latitude dunes, then spring warming fractures shaded crest remnants into blocks that descend and vaporize.
• Sliding blocks account for shallow channels, whereas burrowing behavior produces the deeper, winding linear dune gullies once thought to reflect liquid-driven debris flows.