lundi 9 novembre 2015
Layers and Fractures in Ophir Chasma, Mars
NASA - Mars Reconnaissance Orbiter (MRO) logo.
Nov. 9, 2015
Ophir Chasma forms the northern portion of the vast Mars canyon system Valles Marineris, and this image, acquired on Aug. 10, 2015, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, features a small part of its wall and floor.
The wall rock shows many sedimentary layers and the floor is covered with wind-blown ridges, which are intermediate in size between sand ripples and sand dunes. Rocks protruding on the floor could be volcanic intrusions of once-molten magma that pushed aside the surrounding sedimentary layers and “froze” in place.
Images like this can help geologists study the formation mechanisms of large tectonic systems like Valles Marineris. (The word “tectonics” does not mean the same thing as “plate tectonics.” Tectonics simply refers to large stresses and strains in a planet’s crust. Plate tectonics is the main type of tectonics that Earth has; Mars does not have plate tectonics).
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.
More information and image from High Resolution Imaging Science Experiment (HiRISE): http://www.uahirise.org/
For more information about NASA's Mars Reconnaissance Orbiter (MRO), visit: http://www.nasa.gov/mission_pages/MRO/main/index.html
Image, Text, Credits: NASA/JPL/University of Arizona/Caption: Kirby Runyon/Sarah Loff.
Publié par Orbiter.ch à 13:40