Layered rocks on Mars

Layered rocks on Mars

. These images from Mars Global Surveyor reveal hundreds of layers of similar thickness, texture and pattern that have been exposed in an impact crater in western Arabia Terra (left) and in a canyon located in southwestern Candor Chasma (right) of the Valles Marineris. The numerous, uniform deposits resemble regularly-layered, sedimentary rocks found on Earth. The Martian features could therefore be due to sediments that settled out of liquid water in ancient lakes or shallow seas a few billion years ago. The material might alternatively be due to deposits of airborne dust settling out of the atmosphere, that were later buried and compacted. Arabia is a peninsula of southwestern Asia, bordering the Persian Gulf, the Arabian Sea , and the Red Sea; terra means "extensive land mass"; candor is Latin for "glossy whiteness or sincerity", and chasma is "a deep, elongated, steep-sided depression". (Courtesy of JPL, NASA and Malin Space Science Systems.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University