By Peter Weiss
From Minneapolis, at a meeting of the American Physical Society
The colorful names remain, such as Devil’s Postpile and Giant’s Causeway. Long abandoned, however, are fearsome notions that supernatural beings made these spectacular rock formations in California, Northern Ireland, and elsewhere.
These close-packed, orderly arrays of rock columns, some of them hundreds of meters tall, formed as lava slowly cooled and contracted, scientists believe. However, the exact mechanism that yielded shafts with polygon-shaped cross sections remains obscure.