Crater Lakes Overflowed and Carved Valleys on Mars

A global analysis of Mars images and topography has found that crater lakes in the distant, wet past overflowed and carved valleys.

IMAGE: A colored topographical image showing river valleys on Mars. The outlet canyon Loire Vallis (white line) formed from the overflow of a lake in Parana Basin (outlined in white). Black lines indicate other river valleys formed by processes other than lake overflows. Background is colored Mars Orbiter Laser Altimeter-derived topography over a Thermal Emission Imaging System image mosaic. Image is approximately 650 kilometers across. CREDIT: NASA/GSFC/ JPL ASU

In a new paper published in Nature, with lead authors from The University of Texas at Austin and the Planetary Science Institute, researchers found that some of the surface of Mars was shaped by massive floods that overflowed crater rims. These types of crater lakes are not unheard of here on Earth, and while most people are familiar with the more volcanic kind, we do also have examples of meteor craters with lakes. One of the most famous is Manicouagan in Quebec, Canada.

About 3.5 billion years ago, Mars had a lot of water on its surface, including large lakes, some of which were in impact craters. When the water levels got too high, the lakes burst over the crater rims and flowed down onto the flatter surface below, quickly carving out deep canyons. Again, similar flooding occurred here on Earth at the end of the last ice age, where lake waters burst through into the northwestern United States and Central Asia.

If it happens in one place, it happens in others, right? That’s one of those rules we use in geology and astronomy. An example of one leads to more examples. Such is the case with…