Mars Global Surveyor
Mars Orbiter Camera

Layered Rocks in Grand Canyon

MGS MOC Release No. MOC2-265K, 4 December 2000

This picture showing a variety of layered sedimentary rock outcrops in the Grand Canyon is presented as a reminder that sedimentary rocks record a rich, detailed history of events that occurred in a given place, whether it is in Arizona (such as the picture shown here) or on Mars. Red layers in the foreground of this picture are known to geologists as the Dox Formation or the Dox Sandstone. They were deposited in rivers and floodplains more than a billion years ago. The various layers in the butte in the background formed much later, in the last half-billion years of Earth's history. These other rocks record vast changes including seas, rivers, and sandy deserts. The materials that make up the sediments in these rocks include the detritus of long-vanished mountain ranges and weathered ash from long-extinct volcanoes. In considering the processes that could have created sedimentary rocks on Mars, it is helpful to remember what sedimentary rocks on Earth tell us. On Earth, they can form underwater, they can form on dry land, they can form from sand dunes, river mud, and even biologic debris such as old corals and seashells.

The photo, by Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Principal Investigator, Michael Malin, was taken in 1980. The Colorado River can be seen in the foreground below the red layered rock of the Dox Formation. For those familiar with the Grand Canyon from rafting, the view is near Mile 72 just above the Unkar Rapids.

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Image Credit: Malin Space Science Systems

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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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