rock concretion, Thunderball Canyon, Yukon Territory

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These rock concretions, called cannonball concretions, are found near Haines Junction, Yukon Territory, Canada. They are formed when a cementing material (calcite) in sedimentary rock causes sand and silt to harden around an organic nucleus. Eventually, erosion of the soft sandstone cliff face exposes the rock concretions.

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Size: 5370px × 3581px
Location: Thunderball Canyon, near Haines Junction, Yukon Territory, Canada
Photo credit: © John Sylvester / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: cannonball, canyon, cliffs, concretion, concretions, dramatic, environment, geology, haines, junction, kluane, landscape, mountains, national, nature, north, park, phenomenon, rock, scenic, stones, territory, thunderball, unusual, yukon