erosion
June 19, 2012
A piece of Mars: This is the edge of the northern polar cap on Mars. At the top is the bright icy surface, which is abruptly cut by a cliff. The wall of the cliff shows many layers of different […]
June 18, 2012
A piece of Mars: Sometime in the past, large ripples wandered the dusty lanes of this landscape, sandblasting the hills as they marched on by. Those ripples stopped moving and turned into the fossils you see here. Their bumpy texture […]
June 17, 2012
A piece of Mars: Here is an example of an aeolian enigma. Dunes are depositional, meaning they are made of stuff that piles up on a surface. But these dunes show the strata of the underlying rock within them, which […]
June 4, 2012
A piece of Mars: You can’t easily tell here, but you’re looking at a steep slope that is high at the bottom of the image and flattens out at the top of the image (the small dunes at the top […]
June 3, 2012
A piece of Mars: Bright rocks are being scoured and shaped by dark (bluish) sand. On Mars, active geologic activity is easy to identify: when there aren’t many craters visible, you’re probably looking at a surface that is undergoing change. […]
May 31, 2012
A piece of Mars: Erosion by sandblasting has revealed layers in volcanic rock. Likely nearly horizontal, the wind here has shaped the surface so the layers appear to be festoons, swirling across the landscape. (HiRISE ESP_021627_1975)
May 23, 2012
A piece of Mars: Old, subdued dunes (in blue) near the south pole on Mars. This shows the edge of a dune field, with white rock-strewn surface beyond the sand. Criss-crossing the sand are the tracks that dust devils have […]
May 22, 2012
A piece of Mars: This is what dunes look like when they die. At least on Mars. On Earth they typically get buried or eroded away. On Mars geology works slowly enough that the steep slopes of dunes are gradually […]