Valleys

There is no current or past plate tectonic activity on Mars. But there are many valleys, including an enormous canyon called Valles Marineris (seen above), which appears to be have been created by faults. This canyon is so large that it covers a third of the Martian globe. Valles Marineris is a canyon that stretches about 3,000 kilometers (1,860 miles) and at its deepest point it is 8 km (5 miles) deep. On either side of this monstrous canyon there are intricate river systems and one that extends north. On the east side is evidence of glacial activity which gives another reference point for where the crust of Mars was about 3.8 billion years ago. Above Valles Marineris is another chasm called Hebes Chasma, click here for a photo of layered terrain in Hebes Chasma. Check out the fly through (1.2 MB ) of a tiny section of the eastern portion of Valles Marineris.

Erosion

Some of Mars' river beds are upwards of 4 miles across. On the west side of Valles Marineris is a region called Noctus Labyrenthus.This image (below right) shows a false color view of Noctus Labyrenthus blanketed with haze in the early Martian morning. It contains a large portion of the planet's river formations. These reliefs show similar veination (branching) to rivers on Earth. The image on the top right shows the area around the Pathfinder landing site. Note the erosion patterns. It has clearly been formed by moving liquid, water. These fluid eroded features are divided into two types: outflow channels and valley networks. Noctus Labyrenthus is a valley network. The area around the Mars Pathfinder is an outflow channel, caused by an enormous outflowing of fluid. Note that the outflow channels occur mainly in the young surfaces in the northern lowlands. Valley networks occur throughout the older, heavily-cratered terrains.There seems to have been several catastrophic events in Mars' past. One of which was a flood of biblical proportions. Some kind of heat caused all the permafrost in these massively scarred regions to melt all at once very quickly. This fast melting caused the flood(s) and took land with it, carving out large sections in a short period of time. In the middle is a region near the Schiaperrelli crater. There is a massive amount of wind erosion on these types of flat surfaces. There the wind can reach up to 200 mph. The streaking you see is caused by wind pushing the crater ejectae many miles from its source. On the bottom right and second from bottom right is Orphir Chasma. In this view of Orphir you can see extensive erosion caused by either landslides or flowing water. This regions shows the largest build up of sedimentary deposits on the planet. On the left is a close up of Orphir showing massive amounts of deposits. See the water on Mars section for more information.