The lava flows on the Martian surface are observed to be much longer, probably a result of higher eruption rates and lower surface gravity. Another reason why the volcanoes on Mars are so massive is because the crust on Mars doesn't move the way it does on Earth.
On Earth, the hot spots remain stationary but crustal plates are moving above them. The Hawaiian islands result from the northwesterly movement of the Pacific plate over a stationary hotspot producing lava.
As the plate moves over the hotspot, new volcanoes are formed and the existing ones become extinct. Members Educators Researchers. Search for: Submit Search. Discover Visit Support. Prepare for Re-Entry! Although it has taken billions of years to form, some regions of the mountain may be only a few million years old, relatively young in the lifetime of the solar system.
As such, Olympus Mons may still be an active volcano with the potential to erupt. The tallest volcano in the solar system may also house rock glaciers — rocky debris frozen in ice. Snow and ice deposits above the base of the shield could result in such glaciers. Water-ice insulated by surface dust may exist near the top of the volcano. The tops of these glaciers may host ridges, furrows, and lobes, and be covered by rocks and boulders, and could be as young as four million years old.
Why would such a huge volcano form on Mars but not on Earth? Scientists think that the lower surface gravity of the red planet, combined with higher eruption rates, allowed for the lava on Mars to pile up higher. The presence and absence of tectonic plates could also play an important role in the different kinds of volcanoes. The hot spots of lava under the crust remain in the same location on both planets.
On Earth, however, the movement of the crust prevents the steady buildup of lava. The Hawaiian Islands , for instance, formed as a plate drifted over a hot spot. Each eruption created a small island in a different spot. Subscriber Account active since. Everest might be the tallest mountain on Earth, but it's nothing compared to the tallest volcanic mountain in the solar system, Olympus Mons on our red cousin Mars.
John Brady at Astronomy Central shows, in the image below, what this gargantuan feature would look like if it were on the continent of North America — it would completely cover the state of Arizona!
Like the volcanoes that formed the Hawaiian islands, Olympus Mons is a shield volcano , which is named after its shape, which resembles a warrior's shield.
Shield volcanoes erupt lava that flows more easily than lava from some other eruptions, which means the lava travels a further distance before cooling and hardening giving shield volcanoes their distinctive shape, which you can clearly see in the NASA image below:.
While some scientists think that this last eruption on Olympus Mons marks the last breath of volcanic activity on Mars, others suggest this monstrous volcano is still active despite being dormant for millions of years.
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