Mountains, Mesas, and Box Canyons on the floor of Valles Marineris
Click for full image.
Cool image time! The photo above, cropped, reduced, and rotated to post here, was taken on March 12, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small section of the floor of the giant 2,550-mile-long and 400-mile-wide Valles Marineris canyon on Mars. In fact, this section, as indicated by the black rectangle in the overview map below, is practically in the center of the canyon, at its widest point.
The geology here hints at several Martian processes. The mesas and closed canyons in the north are typical of chaos terrain, where it erosion appears to form along fault lines to create the random intersecting canyons. In other places on Mars, in the mid-latitudes, that erosion appears mostly formed by glacial activity. Here, in Valles Marineris at only 7 degrees north latitude, little ice had been expected.
However, this spot is also in the dead center of a region where orbital data from Europe’s Trace Gas Orbiter (TGO) suggests there is a surprisingly large underground reservoir of hydrogen, which is assumed could only exist if it was locked in water molecules.
In fact, at this spot the data suggests up to 40% of the near-surface material might be composed of water (by weight). If so, that underground reservoir of ice could be causing the erosion that is creating this massive chaos terrain.
Meanwhile, the light-colored mountain in the south is the westernmost nose of a 50-mile-long ridgeline coming down from the canyon’s rim, about 30,000 feet higher. Its dendritic nature, like the hollows that form in the mountains of wet regions on Earth, suggest rainfall and water flowing downhill, wearing away these hollows over eons.
Rain however is almost certainly not the cause. Instead, we could be seeing erosion from wind, or maybe dry ice snow that fell long ago when this region was at a higher latitude when Mars’ rotational tilt was different.
Either way, the massive geology here illustrates the monumental nature of this largest canyon in the solar system, as well as the difficulties of exploring it.
Click for full image.
Cool image time! The photo above, cropped, reduced, and rotated to post here, was taken on March 12, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small section of the floor of the giant 2,550-mile-long and 400-mile-wide Valles Marineris canyon on Mars. In fact, this section, as indicated by the black rectangle in the overview map below, is practically in the center of the canyon, at its widest point.
The geology here hints at several Martian processes. The mesas and closed canyons in the north are typical of chaos terrain, where it erosion appears to form along fault lines to create the random intersecting canyons. In other places on Mars, in the mid-latitudes, that erosion appears mostly formed by glacial activity. Here, in Valles Marineris at only 7 degrees north latitude, little ice had been expected.
However, this spot is also in the dead center of a region where orbital data from Europe’s Trace Gas Orbiter (TGO) suggests there is a surprisingly large underground reservoir of hydrogen, which is assumed could only exist if it was locked in water molecules.
In fact, at this spot the data suggests up to 40% of the near-surface material might be composed of water (by weight). If so, that underground reservoir of ice could be causing the erosion that is creating this massive chaos terrain.
Meanwhile, the light-colored mountain in the south is the westernmost nose of a 50-mile-long ridgeline coming down from the canyon’s rim, about 30,000 feet higher. Its dendritic nature, like the hollows that form in the mountains of wet regions on Earth, suggest rainfall and water flowing downhill, wearing away these hollows over eons.
Rain however is almost certainly not the cause. Instead, we could be seeing erosion from wind, or maybe dry ice snow that fell long ago when this region was at a higher latitude when Mars’ rotational tilt was different.
Either way, the massive geology here illustrates the monumental nature of this largest canyon in the solar system, as well as the difficulties of exploring it.
