Geologic Landforms and Chronostratigraphic History of Charon as Revealed by a Hemispheric Geologic Map
Geologic mapping has been used for over 200 years as a technique to synthesize a complicated surface into a more simplified product, identifying similar types of surface features, and placing them into a relative stratigraphy. Geomorphologic mapping has applied those principles to other terrestrial bodies throughout the solar system and has formed an important product set to understand these surfaces, plan future exploration, and conduct different scientific endeavors. We created a geomorphologic map of the New Horizons encounter hemisphere of Pluto's binary companion, Charon. Ten primary geomorphologic unit categories were identified, covering approximately 35% of Charon's surface, and we used lower resolution data to speculate about other regions of Charon. Over 1,000 linear features were mapped, nearly 90% of them are tectonic in nature, and we use these to provide evidence of Charon being active in its past. Additionally, we placed the mapped features into a chronostratigraphic sequence, and we present a possible surface history for the body. The northern terrain typified by large crustal blocks is the oldest, having fractured early in Charon's history, and potentially similar blocks were submerged in a cryoflow of which the now solid surface of Vulcan Planitia is the remnant today.