Alfonso F. Davila and colleagues analyzed images and topographic data from the Aeolis Mensae region of Mars.
Their analyses indicate that these terrains were eroded by glaciers emanating from the Martian dichotomy boundary.
Collectively, they say their observations suggest that glacial activity could have been an important mechanism of modification of equatorial regions on Mars for three billion years.
Alfonso F. Davila et al., SETI Institute, DOI:10.1130/G34201.1.