Planetary geologist Chris Okubo is on a mission to understand the past roles of ground water and faulting on Mars by studying similar locations on Earth. Okubo works in the Astrogeology Research Program for the U.S. Geological Survey (USGS) in Flagstaff, Ariz.
presence of liquid water on Mars, whether past or present, is a key clue to
whether Mars ever harbored life," Okubo says, explaining his work with
NASA's Mars Reconnaissance Orbiter (MRO), a spacecraft currently orbiting the
red planet. "My research interests are split equally between understanding
deformation on Earth and then applying this knowledge to other planets."
Okubo and colleagues from NASA's Jet Propulsion
Laboratory in California as well as from Nevada, Utah and Italy used high-resolution images from a powerful telescopic
camera aboard the MRO to analyze layered rocks in areas around Mars' equatorial
were looking at rock fractures called 'deformation bands.' We saw hundreds of
small fractures that appear to have directed water through ancient Martian sandstone
that now can be seen on the surface. This is very exciting, because what we're
seeing is the visible effect on the color and texture of rock made by extensive
ground water flow billions of years ago."
and his colleagues made their findings in part based on fieldwork in the
Colorado Plateau in Utah and Arizona, which has similar weathered sandstone
that exposes ancient deformation bands. The rock
formations of the Colorado Plateau generally are valued by planetary
geologists as accessible study sites for comparison to Mars.
commonly form in sandstone as dense clusters
of small-scale faults within deformed rocks. For comparison to the newly observed
Mars features, Okubo and his colleagues studied the deformation bands of the
Navajo and Wingate Sandstones. "Since we have an emerging understanding of
how ground water flows along deformation bands on Earth, this discovery of
deformation bands on Mars is an important link to building our understanding of
how ancient ground water behaved on that planet," Okubo explains.