Mars Global Surveyor
Mars Orbiter Camera
Chain of Pits on Pavonis Mons
MGS MOC Release No. MOC2-99, 23 March 1999
Pavonis Mons is the middle of the three large Tharsis Montes
volcanoes in the martian western hemisphere. Located on the equator
at about 113°W longitude, Pavonis Mons stands as much as 7
kilometers (4 miles) above the surrounding plain. The Mars Global
Surveyor (MGS) Mars Orbiter Camera (MOC) recently spied the above
chain of elliptical pits on the lower east flank of Pavonis Mons. The
picture covers an area 3 kilometers (1.9 miles) wide by 3.4 kilometers
(2.1 miles) in length. The pits are aligned down the center of a 485
meters-(530 yards)-wide, shallow trough. The straight trough and the
pits were both formed by collapse associated with faulting. The scarp
on each side of the trough is a fault line--troughs of this type are
known to geologists as graben. Such features are typically
formed when the ground is being moved apart by tectonic forces, or
when the ground is uplifted by molten rock injected into the near
sub-surface from deeper underground. Both processes may be
contributing to the features seen on Pavonis Mons. The pits follow
the trend of these faults, and indicate the locus of collapse.
Illumination is from the upper left in this image.
Malin Space Science Systems and the California Institute of
Technology built the MOC using spare hardware from the Mars Observer
mission. MSSS operates the camera from its facilities in San Diego,
CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project
operates the Mars Global Surveyor spacecraft with its industrial
partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA
and Denver, CO.
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