NASA Orbiter Reveals Rock Fracture Plumbing on Mars
PASADENA, Calif. – NASA's Mars Reconnaissance Orbiter has revealed
hundreds of small fractures exposed on the Martian surface that billions
of years ago directed flows of water through underground Martian sandstone.
Researchers used images from the spacecraft's High Resolution Imaging
Science Experiment, or HiRISE, camera. Images of layered rock deposits at
equatorial Martian sites show the clusters of fractures to be a type
called deformation bands, caused by stresses below the surface in granular
or porous bedrock.
"Groundwater often flows along fractures such as these, and knowing that
these are deformation bands helps us understand how the underground
plumbing may have worked within these layered deposits," said Chris
Okubo of the U.S. Geological Survey in Flagstaff, Ariz.
Visible effects of water on the color and texture of rock along the
fractures provide evidence that groundwater flowed extensively along
"These structures are important sites for future exploration and
investigations into the geological history of water and water-related
processes on Mars," Okubo and co-authors state in a report published
online this month in the Geological Society of America Bulletin.
Deformation band clusters in Utah sandstones, as on Mars, are a few
meters or yards wide and up to a few kilometers or miles long. They
form from either compression or stretching of underground layers,
and can be precursors to faults. The ones visible at the surface have
become exposed as overlying layers erode away. Deformation bands and
faults can strongly influence the movement of groundwater on Earth and
appear to have been similarly important on Mars, according to this study.
"This study provides a picture of not just surface water erosion, but true
groundwater effects widely distributed over the planet," said Suzanne
Smrekar, deputy project scientist for the Mars Reconnaissance Orbiter
at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Groundwater
movement has important implications for how the temperature and chemistry
of the crust have changed over time, which in turn affects the potential
for habitats for past life."
The recent study focuses on layered deposits in Mars' Capen crater,
approximately 70 kilometers (43 miles) in diameter and 7 degrees north
of the equator. This formerly unnamed crater became notable due to this
discovery of deformation bands within it and was recently assigned a formal
name. The crater was named for the late Charles Capen, who studied Mars
and other objects as an astronomer at JPL's Table Mountain Observatory
in Southern California and at Lowell Observatory, Flagstaff, Ariz.
The HiRISE camera is one of six science instruments on the orbiter. It can
reveal smaller details on the surface than any previous camera to orbit Mars.
The orbiter reached Mars in March 2006 and has returned more data than
all other current and past missions to Mars combined.
The mission is managed by JPL for NASA's Science Mission Directorate. JPL
is managed for NASA by the California Institute of Technology in Pasadena.
Lockheed Martin Space Systems of Denver built the spacecraft. The University
of Arizona operates the HiRISE camera, built by Ball Aerospace and Technology
Corp. of Boulder, Colo.
Images of the deformation band clusters and additional information about the
mission are on the Internet at: http://www.nasa.gov/mro
For more information about NASA and agency programs, visit: http://www.nasa.gov
Media contacts: Dwayne Brown
Jet Propulsion Laboratory, Pasadena, Calif.
Lori Stiles 520-626-4402
University of Arizona, Tucson