Flooded Impact Craters in Hebrus Valles

Hebrus Valles are a complex set of channels in the northern lowlands of Mars just to the west of the Elysium volcanic region.

The channel segments to the north of this image display a variety of features, including streamlined forms and terracing that are suggestive of catastrophic flooding.

However, this observation shows channels of uniform width suggesting more persistent flows eroding into and around two impact craters, each about two hundred meters in diameter. This complex geology may be the result of formation in volcanic terrains as fluid flows erode into basalt and interbedded ash or sediment layers. The channel system is thought to be early Amazonian in age (as far back as 3 billion years ago), which is younger than many of the other outflow channels on Mars.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. (The original image scale is 32.5 centimeters [12.8 inches] per pixel [with 1 x 1 binning]; objects on the order of 98 centimeters [38.6 inches] across are resolved.) North is up.

This is a stereo pair with ESP_073686_2010.

The University of Arizona, in Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., in Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.