re: re: White Rock -> Red Rock - varnished rock?
Reminds me of Canada's Haughton Crater on Devon Island.
National Geographic
Inset picture by Michael Carroll
Even in places near the center of the crater where there seems to be an absense of frost/snow, the ground is lighter. Average temps are 17°C (near 0° Farenheit)
The THEMIS team explanation of the Martian White Rock. If it is made up of volcanic ash, then something else must be holding that ash together and even preserving it...CO2 ice... any ice. ;)
Marcia