London, Sept 21: Lava flow could have covered features on Mars that appear to have experienced catastrophic flooding, and this could make future landing missions for search of past water on the Red Planet more troublesome, according to a new NASA study.

The results follow the detailed examination for more than three months by the agency’s Mars Reconnaissance Orbiter of the valley system called Athabasca Valles, which has long been interpreted as having been carved out by sudden, catastrophic flooding.