Featured Research

from universities, journals, and other organizations

Melas, Candor And Ophir Chasmas: Centre Of Valles Marineris

Date:
March 6, 2005
Source:
European Space Agency
Summary:
New images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show the central part of the 4000-kilometre long Valles Marineris canyon on Mars. It remains unclear how this gigantic geological feature, unparalleled in the Solar System, was formed.

This perspective image, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, shows the central part of the 4000-kilometre long Valles Marineris canyon on Mars. Credits: ESA/DLR/FU Berlin (G. Neukum)

New images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show the central part of the 4000-kilometre long Valles Marineris canyon on Mars. The HRSC obtained the images during during orbits 334 and 360 with a resolution of approximately 21 metres per pixel for the earlier orbit and 30 metres per pixel for the latter.

The scenes show an area of approximately 300 by 600 kilometres and are taken from an image mosaic that was created from the two orbit sequences. The image shown here is located between 3 to 13 South, and 284 to 289 East.

Valles Marineris was named after the US Mariner 9 probe, the first spacecraft to image this enormous feature in 1971. Here, the huge canyon which runs east to west is at its widest in the north-south direction.

It remains unclear how this gigantic geological feature, unparalleled in the Solar System, was formed. Tensions in the upper crust of Mars possibly led to cracking of the highlands. Subsequently, blocks of the crust slid down between these tectonic fractures.

The fracturing of Valles Marineris could have occurred thousands of millions of years ago, when the Tharsis bulge (west of Valles Marineris) began to form as the result of volcanic activity and subsequently grew to the dimensions of greater than a thousand kilometres in diameter and more than ten kilometres high. On Earth, such a tectonic process is called ‘rifting’, presently occurring on a smaller scale in the Kenya rift in eastern Africa.

The collapse of large parts of the highland is an alternative explanation. For instance, extensive amounts of water ice could have been stored beneath the surface and were then melted as a result of thermal activity, most likely the nearby volcanic Tharsis province.

The water could have travelled towards the northern lowlands, leaving cavities beneath the surface where the ice once existed. The roofs could no longer sustain the load of the overlying rocks, so the area collapsed.

Regardless of how Valles Marineris might have formed, it is clear that once the depressions were formed and the surface was topographically structured, heavy erosion then began shaping the landscape.

Two distinct landforms can be distinguished. On one hand, we see sheer cliffs with prominent edges and ridges. These are erosion features that are typical in arid mountain zones on Earth.

Today, the surface of Mars is bone dry, so wind and gravity are the dominant processes that shape the landscape (this might have been much different in the geological past of the planet when Valles Marineris possibly had flowing water or glaciers winding down its slopes).

In contrast, some gigantic ‘hills’ (indeed, between 1000 and 2000 metres high) located on the floors of the valleys have a smoother topography and a more sinuous outline. So far, scientists have no definitive explanation for why these different landforms exist.

Below the northern scarp, there are several landslides, where material was transported over a distance of up to 70 kilometres. Also seen in the image there are several structures suggesting flow of material in the past. Therefore, material could have been deposited in the valleys, making the present floor look heterogeneous.

In the centre of the image, there are surface features that appear similar to ice flows. These were previously identified in pictures from the US Viking probes of the 1970s; their origin remains a mystery. The colour images were processed using the HRSC nadir (vertical view) and three colour channels. The perspective views were calculated from the digital terrain model derived from the stereo channels.

The 3D anaglyph image was created from the nadir channel and one of the stereo channels. Stereoscopic glasses are needed to view the 3D image. Image resolution has been decreased for use on the internet.


Story Source:

The above story is based on materials provided by European Space Agency. Note: Materials may be edited for content and length.


Cite This Page:

European Space Agency. "Melas, Candor And Ophir Chasmas: Centre Of Valles Marineris." ScienceDaily. ScienceDaily, 6 March 2005. <www.sciencedaily.com/releases/2005/02/050222193103.htm>.
European Space Agency. (2005, March 6). Melas, Candor And Ophir Chasmas: Centre Of Valles Marineris. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2005/02/050222193103.htm
European Space Agency. "Melas, Candor And Ophir Chasmas: Centre Of Valles Marineris." ScienceDaily. www.sciencedaily.com/releases/2005/02/050222193103.htm (accessed October 21, 2014).

Share This



More Space & Time News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Comet Siding Spring Grazes Mars' Atmosphere

Comet Siding Spring Grazes Mars' Atmosphere

Newsy (Oct. 19, 2014) A comet from the farthest reaches of the solar system passed extremely close to Mars this weekend, giving astronomers a rare opportunity to study it. Video provided by Newsy
Powered by NewsLook.com
Latin America Launches Communications Satellite

Latin America Launches Communications Satellite

AFP (Oct. 17, 2014) Argentina launches a home-built satellite, a first for Latin America. It will ride a French-made Ariane 5 rocket into orbit, and will provide cell phone, digital TV, Internet and data services to the lower half of South America. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
This Week @ NASA, October 17, 2014

This Week @ NASA, October 17, 2014

NASA (Oct. 17, 2014) Power spacewalk, MAVEN’s “First Light”, Hubble finds extremely distant galaxy and more... Video provided by NASA
Powered by NewsLook.com
Saturn's 'Death Star' Moon Might Have A Hidden Ocean

Saturn's 'Death Star' Moon Might Have A Hidden Ocean

Newsy (Oct. 17, 2014) The smallest of Saturn's main moons, Mimas, wobbles as it orbits. Research reveals it might be due to a global ocean underneath its icy surface. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins