Light-Toned Layering in a Labyrinthus Noctis Pit

Understanding both the spatial and temporal distribution of hydrated (water-bearing) minerals on Mars is essential for deciphering the aqueous history of the planet. Over 300 meters of layered beds are exposed in this trough of Noctis Labyrinthus, at the western edge of Valles Marineris.

The beds are mixtures of light- and dark-toned materials, and include units that contain hydrated minerals, like sulfates and clays. Mapping these minerals and their stratigraphic relationships indicates numerous hydrologic and/or depositional events in localized environments spread over time.

The diversity of materials within the trough implies active hydrologic processes and/or changing chemical conditions, perhaps due to influxes of groundwater from nearby Tharsis volcanism.

http://photojournal.jpl.nasa.gov/catalog/PIA14455