Arabia Terra
This battered topography indicates great age, and Arabia Terra is presumed to be one of the oldest terrains on the planet.
[3][4] Dark slope streaks have been observed in Tikhonravov Basin, a large eroded crater.
[5] These streaks are thought by some to form by dust moving downslope in a way similar to snow avalanches on Earth.
[7] An equatorial belt was noted with a crater age distinctly younger than the northern part of the province and of Noachis Terra to the south.
This was interpreted as an "incipient back-arc system" provoked by the subduction of Mars lowlands under Arabia Terra during Noachian times.
Regional fracture patterns were also explained in this manner, and the rotational instability of the planet as a cause was not supported.
[18] Termed "plains-style caldera complexes", these very low relief volcanic features appear to be older than the large Hesperian-age shield volcanoes of Tharsis or Elysium.
[18] The authors regard crustal thinning due to regional extension to be a more likely explanation for the origin of the volcanic activity than putative subduction.
[19] In the 2011 novel The Martian by Andy Weir, the protagonist encounters a dust storm in Arabia Terra while traveling from Acidalia Planitia to Schiaparelli crater.
A detailed discussion of layering with many Martian examples can be found in Sedimentary Geology of Mars.
One study that used HiRISE pictures found over 17,000 km of ancient river valleys in Arabia Terra.
It has been known for some time that Mars undergoes many large changes in its tilt or obliquity because its two small moons lack the gravity to stabilize it, as the Moon stabilizes Earth; at times the tilt has even been greater than 80 degrees[27][28] Parts of northern Arabia Terra contains the upper plains unit.
It was first investigated in the Deuteronilus Mensae (Ismenius Lacus quadrangle) region, but it occurs in other places as well.
Cracks exposed more surfaces, and consequently more ice in the material sublimates into the planet's thin atmosphere.
