At the mouth of the Red Valley

The 120-mile-long Tinto Vallis is believed to have formed around 3.7 billion years ago, during the early history of Mars.
By | Published: February 18, 2013 | Last updated on May 18, 2023
The image features craters, lava channels and a valley from which water may have once flowed. Dark wind-blown sediments fill the valleys and the floors of the craters. // ESA/DLR/FU Berlin (G. Neukum)
The European Space Agency’s (ESA) Mars Express took a high-resolution stereo image January 13 of the southeast corner of the Amenthes Planum region on Mars, near Palos Crater and the mouth of a well-known sinuous valley, Tinto Vallis.

At the bottom-center of the full-color image, and up close in the first perspective image, is a nearby shorter and wider valley that is fed by a number of tributaries before it joins the mouth of Tinto Vallis, as both empty into Palos Crater just off the bottom of the image.

This computer-generated perspective view of a network of short valleys feeding Palos Crater was created using data from the High-Resolution Stereo Camera on ESA’s Mars Express. The valley’s U-shaped cross section is indicative of a process called groundwater sapping, whereby volcanic heat has melted sub-surface ice, liberating water to the surface and causing the ground around it to collapse. The top left of the image is the periphery of a 60-mile-wide (100km) crater. // ESA/DLR/FU Berlin (G. Neukum)
The 120-mile-long (190 kilometers) Tinto Vallis is seen in the context image and is named after the famous Rio Tinto river in the Andalucía region of Spain. It is believed to have formed around 3.7 billion years ago, during the early history of Mars.

The network of shorter valleys shown in the first perspective image is thought to have formed through volcanic activity melting subsurface ice and liberating water to the martian surface via seeps and springs.

The area imaged by Mars Express January 13, 2013, lies southeast of the Amenthes Planum region and north of Hesperia Planum and shows Tinto Vallis and Palos Crater in broader context. The smaller rectangle shows the region covered in this ESA Mars Express High-Resolution Stereo Camera image release. // NASA MGS MOLA Science Team
If underground water emerges to the surface from the side of a slope — a process that planetary geologists call “groundwater sapping” — it weakens the ground above it, causing it to collapse. Over time, this process may lead to the formation of steep-sided U-shaped valleys. Groundwater sapping is believed to be responsible for erosion seen in many of the valley networks on the Red Planet.

Another eye-catching feature is the relatively deep 20-mile-wide (35km) crater seen in the left-hand portion of the color, topographic, and 3-D images. Spectacular landslides along the crater’s walls can be seen and are particularly evident along the broken southern (left) rim.

This color-coded overhead view is based on an ESA Mars Express High-Resolution Stereo Camera digital terrain model of the region southeast of Amenthes Planum and north of Hesperia Planum, from which the topography of the landscape can be derived. The color coding emphasises the superposed craters on the large 60-mile-wide (100km) crater to the left (south) of the image. Also more clearly seen are the various mesa and buttes within the larger 60 mile crater. At the bottom of the image is a small river valley that feeds into Palos Crater, which may once have hosted a lake. // ESA/DLR/FU Berlin (G. Neukum)
This crater sits on top of at least three older craters, the largest of which is 60 miles (100km) wide and dominates the whole top left half of the 2-D and 3-D anaglyph images. The western rim of this crater continues beyond the image frame and can be more easily distinguished in the context image.

The floor of this 60-mile-wide (100km) crater is chaotic, with flat-topped geological features called mesas and their smaller siblings, buttes, littering the floor. These are probably the result of the removal of subsurface water ice leading to the collapse of weaker material around them, leaving these more-resistant, high-sided features behind. On Earth, the desert regions in Utah are home to many examples of these types of formation.

Computer-generated perspective view of the southeastern corner of the volcanic plains of Amenthes Planum. This view was created using data obtained from the High-Resolution Stereo Camera on ESA’s Mars Express. The image shows a 20-mile-wide (30km) crater, the north eastern rim of which rests against a smooth volcanic trough that may have once transported fluvial and volcanic materials from Palos Crater and Tinto Vallis into Amenthes Planum. // ESA/DLR/FU Berlin (G. Neukum)
Toward the north (right) side of the 2-D images, several smaller craters display smooth, flat floors from infilling by sediments.

The darker regions to the far north and south, shown most clearly in the first color image, are covered in wind-transported basaltic sands.

The smooth low-lying region to the far right and shown in the second perspective image is a small trough that feeds into the broader lava field of Amenthes Planum. The trough has likely been modified by the outflow of material from the ancient lake that may have once existed in Palos Crater, the rim of which can only just be seen at the bottom of the color, topographic, and 3-D images. This smooth, channel-like feature brushes against the rim of a 20-mile-wide (30km) crater, and both have been covered with dark wind-blown materials.

The region southeast of Amenthes Planum and north of Hesperia Planum imaged January 13, 2013, by ESA’s Mars Express using the High-Resolution Stereo Camera (HRSC). Data from HRSC’s nadir channel and one stereo channel have been combined to produce this anaglyph 3-D image that can be viewed using stereoscopic glasses with red–green or red–blue filters. // ESA/DLR/FU Berlin (G. Neukum)
With these recent images, Mars Express continues to show the similarities between regions on Mars with those on our home planet.