Hesperia Planum

Some articles on hesperia planum:

Hesperian Chronology and Stratigraphy - Boundaries and Subdivisions
... System is defined as the base of the ridged plains, which are typified by Hesperia Planum and cover about a third of the planet’s surface ... In eastern Hesperia Planum, the ridged plains overlie early to mid Noachian aged cratered plateau materials (pictured left) ... For example, Hesperia Planum is the referent location for the Lower Hesperian Series ...