MOSCOW, 16 November – RIA news. Large canyons on Mars were not formed due to the constant flow of rivers, but because of the "great flooding" that arose when the walls of volcanic lakes on Mars collapsed. Their photos and descriptions have been published in the journal Geology.
"These terrain features are rapidly disappearing from the face of the Earth, but on Mars, where there is no tectonics and water erosion for a long time, these canyons existed for 3.7 billion years and have survived our original form Now we have the opportunity to study how gigantic water flows moved on its surface in the distant past "- says Caleb Fassett (Caleb Fassett) from the Marshall Space Flight Center of NASA (USA).
In recent years, scientists have found many clues about the fact that rivers, lakes and entire oceans of water existed on the surface of Mars in ancient times. On the other hand, some planetologists believe that even in ancient times Mars was too cold for the permanent existence of the oceans and that its water could be in a liquid state only during periods of volcanic eruptions extinct billions. of years ago.
Recently, these views have been shaken – planetologists have found photographs of some Martian craters at the red planet's equator, such as Istok and Yezero, and in the northern polar latitudes, such as Lyo, traces of water flow which, according to geological standards, were recently tens or hundreds of millions of years back, moving to the surface of Mars.
This discovery has led many scientists to guess how liquid water could reach the surface of Mars and survive there long enough to form a network of deep and very long and branched canals in the rocks near the slopes of these craters.
These disputes, as noted by Fassett, are largely due to the fact that scientists do not yet know exactly how these canyons were born. Their "parents" could be both relatively shallow and slow waters, which have dug these canals for many millions of years, and the "big floods" that hit billions of tons of water in the mountains within hours and days.
Mars is primordial
Fassett and his colleagues found that the second theory was closer to the truth, by studying detailed images of the edges of the Jester crater, recently obtained using the HiRISE camera installed on the MRO probe. This crater could be one of the landing spots of the Mars-2020 rover, which forced NASA scientists to study it in detail.
Using these images, the planetologists created a three-dimensional model of Jezero, which helped them evaluate how much water could cross each of these canyons, taking into account the differences in height between the different sections and the Martian strength of attraction.
If these channels had arisen as a consequence of a gigantic flood, it would be logical to assume that their volume corresponds to how much water has passed through them at the time of their formation. As a result, closer to the crater walls, these canyons should be wider and deeper, and in more distant regions will be considerably smaller.
In the same case, if they flowed from the river waters, the "performance" of the canyon will depend mainly on the local topography, and not on the distance from the edge of the falling crater.
As the MRO images show, the size of the channels was in fact linked to the distance from the walls of Yezero, which indicated their "diluvial" origin. On the one hand, this suggests that there may be large deposits in Mars, but from the other it does not confirm that they could exist for a rather long period, the scientists conclude.