Cannonball Concretion

A sandstone and clay pillar that has been eroded by rain and wind holds up a round, fist-sized rock made of scoria. Captured in the North Unit of Teddy Roosevelt National Park, North Dakota.

comments (3)

Ferdy Christant

Lion

How bizarre. It looks to be a matter of time before the rock starts rolling, right? Posted 11 years ago
1. travismorhardt
  
  Lion
  
  I assume you are correct. After enough erosion has occurred, it should roll right off and into the valley. Here is some information on the geological formations found within this area.
  
  http://www.nps.gov/thro/naturescience/geologicformations.htm Posted 11 years ago
2. travismorhardt
  
  Lion
  
  I assume you are correct. After enough erosion has occurred, it should roll right off and into the valley. Here is some information on the geological formations found within this area.
  
  http://www.nps.gov/thro/naturescience/geologicformations.htm Posted 11 years ago