An interactive rendering of the USGS global geologic map of Mars. Every unit carries its official Description of Map Units text, crater-density statistics, topographic statistics, and model-age ranges. Views are shareable: the URL updates as you navigate — copy it (or use ⧉ share view) to cite an exact view and selected unit.
• Tanaka, K.L., and others (2014). Geologic map of Mars. USGS Scientific Investigations Map 3292, 1:20,000,000. doi:10.3133/sim3292 — geology, structures, DMU.
• Tanaka, K.L., Robbins, S.J., Fortezzo, C.M., Skinner, J.A., Jr., Hare, T.M. (2014). Planet. Space Sci. 95, 11–24. doi:10.1016/j.pss.2013.03.006 — crater densities (Robbins & Hynek 2012 database), elevation/slope statistics.
• Werner, S.C., Tanaka, K.L. (2011). Icarus 215, 603–607 — epoch boundary model ages (Hartmann & Neukum systems).
• IAU Gazetteer of Planetary Nomenclature — feature names.
• NASA Mars Trek — MOLA hillshade tiles.
• Data wrangling of shapefiles & unit colors after E. Lutz, mars_geology_atlas_of_space.
Outcrop areas sum mapped polygons and exclude superposed AHi crater materials. The correlation chart derives epoch spans from unit labels per the pamphlet convention. Geometry is simplified from 1:20M source mapping for web delivery — use the USGS GIS database for analytical work.
All scientific content is U.S. government work (public domain). App code MIT.