At the foot of largest volcano in Solar System – Olympus Mons, Mars

at-the-foot-of-largest-volcano-in-solar-system-olympus-mons-mars

New ESA's images show hundreds of individual lava flows frozen in time on the flanks of Olympus Mons, the largest volcano on Mars and largest known in the Solar System.

Olympus Mons is 624 km (374 mi) in diameter, 25 km (16 mi) high, and is rimmed by a 6 km (4 mi) high scarp. A caldera 80 km (50 mi) wide is located at the summit of Olympus Mons. To compare, the largest volcano on Earth is Mauna Loa. Mauna Loa is 10 km (6.3 mi) high and 120 km (75 mi) across. The volume of Olympus Mons is about 100 times larger than that of Mauna Loa.

It is located between the northwestern edge of the Tharsis region and the eastern edge of Amazonis Planitia and stands about 1,200 km (750 mi) from the other three large Martian volcanoes, collectively called the Tharsis Montes (Arsia Mons, Pavonis Mons, and Ascraeus Mons). The Tharsis Montes are slightly smaller than Olympus Mons.

Olympus Mons, Mars – Topography. Author: UdeCgmt

Like Mauna Kea, Olympus Mons is a shield volcano, with gently sloping sides that extend outwards at low angles. But unlike other shield volcanoes, it has an abrupt cliff edge, or scarp, separating it from the surrounding plains.

The images below, taken on January 21, 2013 by ESA’s Mars Express, focus on the southeast segment of the giant volcano.

The scarp circles the entire volcano, in places reaching 9 km high. It was likely formed during a number of catastrophic landslides on the flanks of the volcano, during which the resulting debris was transported several hundred kilometers beyond the extent of these images.

Lava flows cover the base of the volcano, punctuated by a handful of pointy and flat-topped blocks that were either rotated or uplifted during the collapse.

A context image showing where a portion of Olympus Mons was imaged by the High Resolution Stereo Camera on ESA’s Mars Express on 21 January 2013 (orbit 11524), with a ground resolution of approximately 17 m per pixel. The image centre is located at approximately 14°N / 229°E. The outline of the orbit is indicated; the region presented in the corresponding image release is the inner rectangle. Copyright NASA MGS MOLA Science Team

Extensive networks of narrow, overlapping lava flows are proof of an extremely active volcanic past. The lava, long since solidified, once spilled down the natural contours of the volcano, spreading out into broad fans as it reached the scarp and plains below.

Flows that ended before reaching the scarp did so with rounded tongues, as the lava cooled and crept to a stop.

Lava once flowed down the flanks of the Olympus Mons volcano, spilling out onto the surrounding plains. Here, the paths of numerous individual lava flows can be seen curving around natural obstacles and cascading like waterfalls over cliff edges.

Random pointed and flat-topped blocks protrude from the flank edges, rotated or uplifted as the sides of the volcano collapsed.

Only a few very faint traces of ancient lava channels can be seen in the surrounding plain, which was flooded by a later outpouring of lava.

The image was taken by the High Resolution Stereo Camera on ESA’s Mars Express on 21 January 2013 (orbit 11524), with a ground resolution of approximately 17 m per pixel. The image centre is located at approximately 14°N / 229°E. Copyright ESA/DLR/FU Berlin (G. Neukum)

Data from the nadir channel and one stereo channel of the High Resolution Stereo Camera on ESA’s Mars Express have been combined to produce this anaglyph 3D image of the flanks of Olympus Mons which can be viewed using stereoscopic glasses with red–green or red–blue filters.

The image was taken on 21 January 2013 (orbit 11524), with a ground resolution of approximately 17 m per pixel. The image centre is located at approximately 14°N / 229°E. Copyright ESA/DLR/FU Berlin (G. Neukum)

The occurrence of only a few small impact craters shows that it is relatively young compared with more heavily cratered regions elsewhere on Mars – the older the surface, the greater the exposure time to impact events by asteroids or comets.

Furthermore, by looking at how the lava flows overlap, one can determine their relative ages: those that lie on top, cutting through and overprinting other flows, are the youngest.

For example, the vast lava plain surrounding the volcano truncates the majority of lava flows extending from the flanks, suggesting it is younger still, and that it originated from a location outside of this scene.

The volcanic region hosting Olympus Mons and several other large volcanoes is thought to have been active until tens of millions of years ago, relatively recent on the planet’s geological timescale that spans 4.6 billion years. (ESA)

Earth vs Mars

The main difference between the volcanoes on Mars and Earth is their size. Volcanoes in the Tharsis region of Mars are 10 to 100 times larger than those anywhere on Earth. The lava flows on the Martian surface are observed to be much longer, probably a result of higher eruption rates and lower surface gravity.

Schematic view of Olympus Mons: Comparison of Olympus Mons with the highest mountains on Earth. In front of the central part of Olympus Mons are shown the largest terrestrial volcanic mountain, the island of Hawaii in the Pacific with its undersea pedestal, and the Mount Everest massif of the Himalayas. Author/uploader: Stevy76

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. (Learn this difference via video here) 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. This distributes the total volume of lava among many volcanoes rather than one large volcano. On Mars, the crust remains stationary and the lava piles up in one, very large volcano. (JPL)

Featured image copyright ESA/DLR/FU Berlin (G. Neukum)

If you value what we do here, create your ad-free account and support our journalism.

Share:

Related articles

Producing content you read on this website takes a lot of time, effort, and hard work. If you value what we do here, select the level of your support and register your account.

Your support makes this project fully self-sustainable and keeps us independent and focused on the content we love to create and share.

All our supporters can browse the website without ads, allowing much faster speeds and a clean interface. Your comments will be instantly approved and you’ll have a direct line of communication with us from within your account dashboard. You can suggest new features and apps and you’ll be able to use them before they go live.

You can choose the level of your support.

Stay kind, vigilant and ready!

$5 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$50 /year

$10 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$100 /year

$25 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$200 /year

You can also support us by sending us a one-off payment using PayPal:

Leave a reply