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Landslide bunched up terrain near massive Mars volcano

Elizabeth Howell, News Writer
May 4, 2013, 7:00 UTC

Sen—Scars and wrinkles mark the landscape in an area some 200 kilometres east of Olympus Mons -- a giant dormant volcano on Mars -- in new pictures released by the European Space Agency's Mars Express spacecraft.

The rumples came after part of the lower part of the now two-kilometre-high volcano collapsed, perhaps due to changes in water beneath the surface, scientists stated.

"During the collapse, rocky debris slid down and out over hundreds of kilometres of the surrounding volcanic plains, giving rise to the rough-textured aureole seen today," ESA stated.

An aureole is a term from the Latin "circle of light." This particular region, called Sulci Gordii, is just one of several surrounding the massive volcano.

The geologic word sulci refers to hills and valleys that are approximately parallel on Mars. This ragged landscape probably occurred when rocks and other debris came off the volcano, then expanded and compressed during its journey across the surface. Rougher crags appeared as erosion eliminated the lighter bits of the debris between the apexes.

"By studying complex regions like this – and by comparing them to similar examples here on Earth – planetary scientists learn more about the geological processes that dominated ancient Mars, when it was an active planet," ESA stated.

"Just as on Earth, the scene at Sulci Gordii tells us that volcanoes can suffer dramatic collapses that transport vast quantities of material across hundreds of kilometres, where it is subsequently sculpted by wind, water and tectonic forces."

The latest set of pictures comes on the eve of the Mars probe's 10th anniversary of its June 2, 2003 launch. Mars Express, so called because it was built rapidly, was based upon similar technology to that of the failed Mars 96 probe, and the Rosetta mission that is on its way to Comet 67P/Churyumov-Gerasimenko.

Mars Express included two components, an orbiter and a lander that was called Beagle 2. The lander failed to make it to the surface safely, but the orbiter has been returning pictures and information now for close to a decade.

Mars Express is supposed to help scientists understand the role of subsurface water on Mars in shaping the Red Planet. Several rovers deployed by NASA have shown water flowing on the surface at some point in the recent past. A few months ago, for example, the Curiosity rover found evidence that it was wandering in what used to be a hip-high streambed.

Underwater channels are less known on Mars as they are invisible to the surface and require special equipment to look at. In March, however, NASA released images of a 1,000-kilometre subsurface trench mapped by its Mars Reconnaissance Orbiter. The agency speculated that a volcano or earthquake pushed water out onto the surface at some point in the past half-billion years.

Other notable discoveries by Mars Express include evidence of processes such as methane gas, volcanism and possible alteration of the landscape by glaciation.