Image Shows Much-Battered Mars Volcano
November 9, 2011 by UPI - United Press International, Inc.
PARIS, Nov. 8 (UPI) — The European Space Agency’s Mars Express orbiter has captured an image of a large extinct volcano that’s been battered and deformed over eons, the agency said.
While huge by Earth standards at 5 miles high with a 95-mile diameter base, the Tharsis Tholus volcano is just an average-sized one on Mars, an ESA release said Tuesday.
However, its battered condition makes it stand out, scientists say.
Evidence of dramatic events in the volcano’s 4-billion-year history can be seen in the image taken by the HRSC high-resolution camera on the Mars Express.
At least two large sections have collapsed around its eastern and western flanks, and the circular caldera is ringed by faults that have caused to the floor of the carter to subside by as much as 1.6 miles.
Scientists say they believe the volcano completely emptied its magma chamber during eruptions, and as the lava ran out onto the surface the chamber roof was no longer able to support its own weight and sank.