March 9, 2009

Mars volcano may supply water clues

U.S. scientists say the 15-mile-high Olympus Mons volcano on Mars might answer the question of whether that planet ever had, or still has, water.

Rice University Assistant Professor Patrick McGovern and Associate Professor Julia Morgan used an algorithm to analyze the volcano's structure. They determined that only the presence of ancient clay sediments could account for the volcano's asymmetric shape -- and the presence of sediment indicates water was, or is, involved.

Olympus Mons slopes gently from its foothills to the caldera, a distance of more than 150 miles. The researchers say that shallow slope is a clue to what lies beneath. They said that if they were able to start digging on the northwest side of Olympus Mons, they probably would eventually find clay sediment deposited there billions of years ago.

Their research is detailed in the journal Geology.