Tag Archives: erosion

Ripples of rock

A Piece of Mars: To the upper right of this 0.85x0.6 km (0.53x0.37 mi) scene is a flat-lying plain strewn with large ripples. To the lower left is a rugged hill with gray rock laced with white veins (this might ...

The corpse of a dune

A Piece of Mars: The rippled darker patch in this 600x600 m (0.37x0.37 mi) scene is the former site of a sand dune. This is one of a few "dune corpses" found just upwind of a dune field in Holden ...

Overhang

A Piece of Mars: There's a fabric of erosion in this 1x1 km (0.62x0.62 mi) scene, with the main wind blowing from lower right to upper left (and if you look carefully you'll see there's a second, subtler fabric a ...

Just do it

A Piece of Mars: It's all about wind scour here in this 0.75x0.75 km (0.47x0.47 mi) view. The big "swoop" is an erosional channel dug into the surface by winds (blowing from the lower left) trying to erode the hills ...

Dust trapped on the lee side

A Piece of Mars: This 0.95x1 km (.59x.62 mi) scene shows the center of a small dune field. The dunes are shaped by three winds blowing from three different directions: from the west-southwest, east, and south. The north-facing slopes are ...

Endless wind

A Piece of Mars: This 2.88x1.13 km (1.79x0.70 mi) scene shows quintessential Mars, with a 670 m diameter impact crater heavily modified by wind erosion. Both the crater floor and the surrounding terrain are covered by what is likely loosely-cemented ...

Wind and maybe water too

A Piece of Mars: Along the right side of this 0.5x0.5 km (0.31x0.31 mi) scene is the rim of a crater - the stripes are layers exposed (and then perhaps draped by falling ejecta) as the crater formed. To the ...

Exhumed dunes!

A Piece of Mars: The large dunes in the middle of this 375x450 m (0.23x0.28 mi) scene run along a valley (the small dunes at top and bottom are on high ground). What's amazing about this is that the ends ...

Cross-strata or not?

A Piece of Mars: Sand dunes are one of the few sedimentary phenomena that leave behind layers that aren't horizontal. They tend to have a characteristic lean to them (and we call them cross-strata). So when I see something that ...

Sand tails

A Piece of Mars: Up on the tallest volcanoes, the wind screams downhill at night. This 500x500m (0.31x0.31 mi) scene shows how dust is carried downhill, but only that which is trapped behind boulders and crater rims sticks around. The ...