Karlbark's Fotothing

(More slides from a photo-tour of a friend & me in 1989).

-This is from Rauðhólar (Redhills) just outside Reykjavik.
They are pseudocraters that are formed when lava runs over wetlands, marshes, ponds, etc. The heat causes the water to turn into steam wich explodes up through the surface of the lava, leaving craters and hills.

Unfortunately the volcanic gravel was mined during world war 2 for use as material for laying the runways of Reykjavik airport. (There was only a primitive grass runway at the time). Rauðhólar were finally preserved by law in 1974.

Pseudocraters have also been discovered on Mars, which would suggest that there was once water on that planet.