Geologic Map of the MTM-85000 Quadrangle, Mars

the geologic map presented here covers the portion of Mars between latitudes 82.5oS to 87.5oS, longitudes -20oW to 20oW. The Viking Orbiter 2 images used to construct the photomosaic base used for mapping were taken during the southern summer of 1977, with resolutions no better than 140 meters/pixel. A digital mosaic of Mariner 9 images was also constructed to aid in mapping. The Mariner 9 images were taken during the southern summer of 1971-72, and have resolutions as high as 85 meters/pixel. However, usefulness of the Mariner 9 mosaic is limited by incomplete coverage and atmospheric dust opacity.