Overview
- The peer-reviewed study, published October 8 in Geophysical Research Letters, reproduced the gullies in a low-pressure Mars chamber at The Open University.
- Under Martian conditions, sublimating CO2 generated high-pressure gas that blasted sand away, driving ice blocks downslope as they excavated channels.
- Steep slopes produced fast sliding and shallow, straighter cuts, whereas gentler slopes led to burrowing that formed deeper, sinuous trenches with raised levees and pit-like endings.
- The mechanism matches seasonal activity on southern mid-latitude dunes where winter CO2 frost up to roughly 70 cm thick breaks into blocks that detach and move in spring.
- The findings remove liquid water as a required agent for these features and indicate that slope, microclimate, and fine, uniform sand control where gullies develop.