Page 50 - Super Earth Encyclopedia

SPECTACULAR

SIX-SIDED STONES

GIANT’S CAUSEWAY

Sixty million years ago, powerful forces dragging
North America away from Europe opened a rift in
Earth’s crust on the western fringes of what is now
Britain. The rift erupted floods of molten basalt—the
rock that forms the ocean floors. As the basalt cooled
and solidified, it started to shrink, splitting into
thousands of regular geometric columns. Now worn
away by the pounding waves of the Atlantic Ocean,
they form a staircase of stepping stones leading
down to the sea and beyond.

AT A GLANCE

• LOCATION Northeast coast
of Northern Ireland
• EXTENT About ½ mile (1 km)

• FORMATION Cooling of basaltic
lava flow from a volcanic eruption
• AGE About 60 million years old

STATS AND FACTS
FORMIDABLE FORMATIONS
COLUMN SHAPES FORMATIONS
The Giant’s Causeway Most columns Some formations
is a packed cluster of have six sides but have names such
more than 40,000 others have four, as Wishing Chair
interlocking columns. five, seven, or and Shepherd’s
These have formed even eight sides. Steps.
from many separate
lava flows, stacked one LAVA The solidified lava flow is
on top of the other. up to 92 ft (28 m) thick.
m 10 20 30 40

ft 50 100
COLUMN HEIGHT
UP TO
39

FEET
(12 M)
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