Friday, February 6, 2009

Columnar jointing...

spotted in high resolution images of a crater wall on Mars (click to enlarge.) A recent technical paper describes the discovery of these volcanically-generated structures that result from the cooling of ponded lava. These structures are very common in the Miocene-age flood basalts on the Columbia Plateau in eastern Washington. Moreover, the suspected pillow structures seen in the image strongly suggests the presence of water coeval with the extrusion of the lava flow.

I tweaked the image a bit by rotating it so that the downslope direction is to the lower right, and by making slight adjustments to brightness/contrast. The annotations in red are also mine. HiRISE image PSP_005917_2020 courtesy NASA/JPL.

Wanna see Mars? It's as close as a short drive to the Grand Coulee.


  1. True the pillows could suggest water, but couldn't the pillows also form with contact to any liquid? :)

  2. Pillow/palagonite structures are formed on Earth where lava interacts with water, so why not on Mars? What other liquids could have existed in abundance on the surface of Mars, and be an alternative?