Tag Archives: erosion

Remnants of erosion

A Piece of Mars: The gray area in the center of the 480x270 m (0.3x0.17 mi) area is an erosional remnant: once, more of this area was covered by the gray stuff, but some of it has eroded away (most ...

That which curves and that which is straight

A Piece of Mars: The long meandering lines snaking across the image (3.2x1.8 km or 2x1.1 mi across) are inverted channels. They are river deposits that once were the lowest part of the landscape (rivers always are), but then the ...

Windy windows

A Piece of Mars: This 0.96x0.54 km (0.6x0.33 mi) area shows ripples forming on a layer of dark gray material. In a few spots, the gray layer has been eroded away (probably by wind scour), revealing the lighter, tan-colored ...

Layered winds

A piece of Mars: On the left is high ground, covered with dunes (or maybe they're ripples) running from upper left to lower right. On the right is low ground, covered in deeply eroded dunes (ripples?) running almost from left ...

What is burying what?

A piece of Mars: There's an egg-shaped plateau here (the whole scene is 480x270 m or 525x295 yd across, the "egg" is ~100 m long). It's partly covered by dunes that have extended across it. Or were the dunes there ...

Wind stripes

A piece of Mars: Yes, I post a lot of pictures of martian dunes with striped patterns. They're all distinct and beautiful. So here's another one, 480x270 m (0.3x0.17 mi) in size. These beasts moved from right to left across ...

Melty dunes

A Piece of Mars: With all due apologies to followers of the show Coupling, I have to call these things "melty dunes". This link shows what a crisp dune should look like. The dunes in this 600x450 m (0.37x0.28 mi) ...

Wind eroded mantle

A piece of Mars: The curving ridge of a mountain has signs of many small landslides. Mantled on top of these is an older set of landslides that has been partially eroded away. The rippled edge of this older deposit ...

Bearded craters and dunes

A piece of Mars: This 600x450 m (1969x1476 ft) scene has a complex sedimentary history. How are bearded craters and dunes formed? They weren't always bearded. At some point, a deposit of bright material accumulated on this surface, and was ...

Inverted crater

A piece of Mars: This circular hill is 200 m (~656 ft) across and ~48 m (~160 ft) high. It stands alone on a relatively flat plain. Why is it there? The surface here used to be ~48 m higher ...