Science has long known that there was once liquid water on the surface of Mars. Until now, however, it was unclear how much water on Mars actually shaped the landscape. As part of a new study, scientists have taken a closer look at this fact and have found several unexpected results. First of all, the rivers of the Red Planet apparently had a decisive influence on the excavations formed by the valleys.
Water on Mars: Floods Shaping the Surface
Scientists from around the world have studied the surface of Earth's closest neighbor for decades. Particularly in the search for water on Mars, its craters play an important role. Once upon a time, sedimentary deposits moved across the surface of Mars on an enormous scale. The reason for this, it is assumed, was the flooding caused by the outburst of giant lakes in the craters. This discovery, published in the journalNature , came as a surprise to the authors of the study.
“This is a somewhat surprising result,” Sci-News quotes Dr. Tim Goudge, a researcher at the University of Texas at Austin and at CIFAR. For a long time, such floods were considered one-time anomalies. They occurred when water flowed out of the edges of the craters. According to the researchers, such events could cause catastrophic floods, which, as they progressed, left huge river valleys behind them.
Two types of river valleys
Remote sensing images from satellites continue to investigate the remains of destroyed crater lakes on Mars. “But until now, the crater lakes and the river valleys outgoing from them have been explored mostly only pointwise and one by one,” says Dr. Goudzha. "So this is just the first study to investigate how 262 hacked and escaped Martian lakes formed the surface of the Red Planet as a whole."
The team conducting this new study classified the river valleys of Mars, roughly dividing them into two categories:
- Class 1: valleys formed along the edges of craters.
- Class 2: valleys formed elsewhere in the landscape.
The first category assumes that the respective valleys were formed within a short time during the flood. The second type assumes the gradual formation of the relief over time.
Surface of Mars: Great Difference in Valleys
Researchers have found that in the valleys of class 1, erosion reached almost a quarter of the volume of erosion of all river valleys on the planet, and this despite the fact that they account for only 3 percent of the total length of the valleys. This discrepancy can be explained by the fact that "the valleys that played the role of drainage drains are much deeper than other valleys," explains Dr. Alexander Morgan of the Institute of Planetary Science. Thus, water has become the cause of global transformations of the picture of the Red Planet.
Such lake outbursts could significantly reshape the surface of Mars. The authors of the study even suggested that they could have influenced the formation of other river valleys located in the vicinity. "This theory represents a possible alternative explanation for the unique topography of river valleys on Mars, which is traditionally associated with climate," they summarize in their scientific article.