TEMPE, Ariz., Dec. 21 (UPI) -- Two Arizona State University geologists say features at the Opportunity landing site on Mars were formed not by a lake, but by constant meteorite strikes.
The site where the Mars Exploration Rover Opportunity landed has sediments and layered structures that are thought to be formed by the evaporation of an acidic salty sea. The prevailing thought is that when the Martian sea existed it may have supported life forms and thus would be a prime site to explore for fossils.
However, ASU geologists L. Paul Knauth and Donald Burt -- along with Kenneth Wohletz of Los Alamos National Laboratory -- say base surges resulting from massive explosions caused by meteorite strikes offer a simpler and more consistent explanation for the rock formations and sediment layers.
Their research could impact where and how scientists continue their exploration of Mars in search for past life forms.
The geologists say subsequent weathering by inter-granular water films can account for all of the features observed without invoking shallow seas, lakes or near surface aquifers.
"Layered sequences observed elsewhere on heavily cratered Mars and attributed to wind, water or volcanism may well have formed similarly," they added
The research appears in the journal Nature.