Elton and Bernie debunked

Above and below are images of the Melas Chasma, the Martian equivalent of the Grand Canyon (on steroids, more than 5 miles in depth).

From the DLR site:

There are few places on Mars lower than this. The floor of Melas Chasma sinks nine kilometres below the surrounding plains. New images from the German Aerospace Centre (Deutsche Zentrum für Luft- und Raumfahrt; DLR) operated High Resolution Stereo Camera on ESA's Mars Express orbiter highlight the complex history of this enormous martian canyon.

Melas Chasma is part of the huge Valles Marineris rift valley, which stretches for more than 4000 kilometres. Around Melas Chasma, there is abundant evidence for water having flowed on Mars in the past. Apart from ancient water-cut channels, there are lighter-coloured deposits of sulphate components that were probably deposited in a former lake.

When we finally colonize Mars, this area is a good bet to be the location, because it has the highest natural air-pressure on the planet, resulting in temperatures that would eventually prove hospitable, by Earth standards. Meaning that, in all probability, you are looking at the site of a twenty-third century D.R. Horton subdivision.

(presenting Meandering Martian Meadows, at Melas Creek—starting in the 290's)