Published on April 12th, 2011 | by Yellow Magpie6
Planet Mars’s Volcanoes: A Stunningly Mysterious World With Colossal Vents
Planet Mars’s Volcanoes
Planet Mars has piqued our interest since time immemorial. One aspect that particularly caught our imagination has been its volcanoes. This curiosity about Martian geology and volcanoes was stoked even further when we started receiving pictures of the planet’s surface from our space probes and space landers.
Now, we know a great deal about planet Mars’s volcanoes but still mysteries remain unanswered.
A Myriad Of Mountains And Volcanoes
There are obvious signs of Mars’s previous geological activity. Its volcanoes and canyons are the most obvious indicators of this. Mars’s largest volcanoes are perched on top of what is known as the Tharsis Rise, which is a huge upland area, or bulge in the surface.
The Tharsis Rise is 4,000 kilometres (2,500 miles) in width and ten kilometres (six miles) in height. The largest volcano of a group of four is Olympus Mons, the highest mountain in the Solar System which measures an astonishing 27 kilometres (17 miles) in height.
The group of volcanoes are all shield varieties which have very shallow gradients.
But shield volcanoes are not the only type to be found on planet Mars. The Pateras are oval-shaped marks on the surface where lava poured up through fissures in the crust of the planet.
Alba Mons is the largest volcano on Mars with a diameter of 2,000 kilometres (1,200 miles), rising to a height of over six kilometres (four miles).
To give you some idea of this scale. The distance between Berlin and Moscow is only 1,600 kilometres (1,000 miles).
Mars’s Volcano: Olympus Mons
The highest volcano in the Solar System, Olympus Mons, is a colossal feature on the Martian landscape. The largest volcano in the Tharsis Rise, Olympic Mons measures an astonishing 22 kilometres (13 miles) in height and 600 kilometres (373 miles in width).
To put this in perspective, the highest mountain on Earth, Mount Everest, is only 8,848 metres (5.5 miles) above sea level.
However, as planet Mars has no oceans, a better comparison would be Mauna Kea which is over 10,000 metres ( 6.2 miles) when it is measured from the ocean floor upwards.
To give you some perspective of the incline of Olympus Mons. If you stood on the surface of the volcano you would have no idea that the ground was sloped. The ground would look flat in all directions.
The Mystery Of Martian’ Volcanoes
The volcanoes on planet Mars present quite a conundrum to geologists and volcanologists. It is unclear what forces are responsible for volcanic eruptions on the red planet.
Unlike, the Earth, Mars does not have tectonic plates. This doesn’t pose a problem for scientists though, as it is possible for planets to have large volcanic eruptions periodically every hundred million years or so as internal pressure builds up, as in the case with Venus.
However, such volcanic activity would cause the planet’s surface to be renewed with thick layers of lava. Such resurfacing has never occurred on Mars.
A theory has been created to explain planet Mars’s apparent geological eccentricity. It is thought that because of the planet’s relatively small size, there is never enough pressure for such large scale resurfacing like what occurs on Venus. Instead it is believed that hot spots are formed which melt the planet’s surface pouring out lava.
However, volcanic activity is not limited to the Rise as all throughout the planet’s surfaces there is evidence of eruptions.
Will Planet Mars’s Volcanoes Erupt Again?
The most pertinent question you could ask about Martian volcanoes is ‘Will they erupt again?‘. This is an extremely difficult question to answer and the honest response is that we just don’t know.
Although we can never be sure – the history of Mars suggest that an eruption may be due. The last one is believed to have occurred as recently as 150 million years ago.
Mars has some of the most spectacular volcanoes in the Solar System. Even though they are currently dormant they are a potent reminder of the powers of nature and the huge, incomprehensible forces that are found in the Universe.
Highly Recommended Reading
Check out Yellow Magpie’s The Solar Maximum: The Years The Earth Is Left Defenceless, as well as The Planet Mars: Our Infatuation With The Red Neighbour, Mars’s Moons: The Oddness Of Phobos And Deimos, Terraforming Mars: How To Create Another Home Planet, The Planet Mars And The Valles Marineris: A Wonderland Of Canyons and The Red Planet And Water: Is There Life On Mars? for more insight into the Red Planet.
If you would like to find out more about volcanoes in general check out Yellow Magpie’s Volcanoes: Force Of Nature And Wonder.
You may also wish to take a gander at The Solar System And Beyond: A Guide To The Cosmos.
Cosmos is a highly recommended book. It contains large, full-page pictures of Mars and writing on the subject by the highly competent author, Giles Sparrow.
For people living in Ireland or the United Kingdom, you can access: Cosmos from here.
For those who live in Canada, you can obtain: Cosmos here.
For Germany: Cosmos.
For France: Cosmos.