Mars Bears the Signs of Floods

A new scientific study comes to support previous researches that showed that ancient Martian lava flows might have been cooled off faster than usual, most likely by massive floods. The rock formations exhibit the same characteristics as similar formations on Earth, and  Mars is the only celestial body where such shapes have been observed, except for our planet. According to the investigation, parts of the Red Planet were occasionally flooded, as ice from glaciers entered valleys with seismic activities.

These columnar joints, which are fractures of sorts, have been thought to be unique for our planet alone, simply because Earth has been considered to be the only place where liquid water and volcanic lava could come together. However, deeper studies of Mars have led to the conclusion that its poles are still covered in ice sheets, with 95 percent water purity, which are now buried under a thin layer of rock deposits and sand.

Along with the many ditches discovered in crater valleys, the picture of Mars' past now looks more like that of a place where water abounded, before it all disappeared millions of years ago. It's now up to astronomers to determine the exact role that water played in the geological development of our neighboring planet. For the new research, geophysicist Moses Milazzo, from the US Geological Survey in Flagstaff, Arizona, has collaborated with the team operating the HiRISE camera, an instrument aboard NASA's Mars Reconnaissance Orbiter (MRO).

The paper has been published in a recent issue of the journal Geology, and argues that columnar joints occur when molten lava contracts, usually at temperatures lower than usual. That means that water may have very well accelerated this process, giving birth to the 30 meter (100 foot)-high columns. Most of them are about 1 meter (3 feet) in diameter, and the largest batch discovered adorns the tilted walls of an impact crater. “The HiRISE instrument just barely has the resolution to pick out the columns if they're facing the camera with the perfect orientation,” Milazzo said.

According to the scientist, the formations could only have appeared if lava flows in the region were systematically flooded by water, for up to several weeks or even months. It's only through repetitive processes such as this one that the formations they have identified could have appeared. And that means that the amount of water on the Red Planet was at the time plentiful, to say the least.