Aonia Terra

It covers latitudes 30 to 81 South and longitudes 60 to 163 W.[2] Aonia Terra lies in the Phaethontis, Thaumasia and the Australe quadrangles of Mars.

The feature are bordered by Terra Sirenum within the range of Icaria Fossae to the northwest the highland area which includes Claritas and Coracis Fossae as well as Warrego Valles towards the north, Argyre Planitia to the east and Cavi Angusti, Australe Scopuli and Australe Planum to the south.

The region consists of a few plana (plains) including Aonia, Icaria, Parva and most of Bosporos as well as the west of Argentea Planum.

It would be known as Aonius Sinus, one of Schiaparelli's feature names and was thought to be a bay of Mare Australe.

Various measurements and calculations show that liquid water could exist in aquifers at the usual depths where gullies begin.

[7] One variation of this model is that rising hot magma could have melted ice in the ground and caused water to flow in aquifers.

[10] As for the next theory, much of the surface of Mars is covered by a thick smooth mantle that is thought to be a mixture of ice and dust.

[11][12][13] This ice-rich mantle, a few yards thick, smooths the land, but in places it has a bumpy texture, resembling the surface of a basketball.

[16] Changes in Mars's orbit and tilt cause significant changes in the distribution of water ice from polar regions down to latitudes equivalent to Texas.

The water comes back to ground at lower latitudes as deposits of frost or snow mixed generously with dust.

During a warmer climate, the first few meters of ground could thaw and produce a "debris flow" similar to those on the dry and cold Greenland east coast.

[21] Since the gullies occur on steep slopes only a small decrease of the shear strength of the soil particles is needed to begin the flow.

These occur in the southern portion of the region that is also included in the Mare Australe quadrangle (e.g. Heaviside and Stoney).