Olympus Mons Mons aureole deposits (discussed below). Olympus Mons lies at the edge of the Tharsis bulge, an ancient vast volcanic plateau likely formed by the end of the Noachian Period. During the Hesperian, when Olympus Mons began to form, the volcano was located on a shallow slope that descended from the high in Tharsis into the northern lowland basins. Over time, these basins received large volumes of sediment eroded from Tharsis and the southern highlands. The sediments likely contained abundant Noachian-aged phyllosilicates (clays) formed during an early period on Mars when surface water was abundant, and were thickest in the northwest
Tohil Mons Tohil Mons Tohil Mons is a mountain on Io, one of Jupiter's moons. It stands at 5400 m (18,000 feet) and is located in the Culann–Tohil region of Io's antijovian hemisphere. It was named after the Mayan weather god Tohil. Tohil Mons is one of the most geologically complex mountains in the Solar System as the mountain shows evidence of forming from other mountains through tectonic and erosional processes, in combination with silicate volcanic rock or magma activity. The main massif of Tohil Mons has ridges and grooves, which indicate the presence of materials that have been tectonically displaced, including