Olympus Mons is supported by a thick lithosphere. The extraordinary size of Olympus Mons is likely because Mars lacks mobile tectonic plates. Unlike on Earth, the crust of Mars remains fixed over a stationary hotspot, and a volcano can continue to discharge lava until it reaches an enormous height. Being a shield volcano, Olympus Mons has a very gently sloping profile. The average slope on the volcano's flanks is only 5°. Slopes are steepest near the middle part of the flanks and grow shallower toward the base, giving the flanks a concave upward profile. The shape of Olympus Mons is distinctly asymmetrical
Erebor Mons Erebor Mons Erebor Mons is a mountain on Titan, the largest moon of the planet Saturn. It is located near Titan's equator, between 4-5° south and 35-36° west, centered on , in the western part of Quivira region. It is 40 km across, more than 1 km high and has lobate flow features to its north and east. It is probably a cryovolcano. Erebor Mons is situated about 470 km to the north-northeast of a larger cryovolcanic construct, Doom Mons. Erebor Mons is one of the highest known mountains of Titan, but it is not readily discernible on radar or