Devil's Postpile 1
September 15, 2009

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Mammoth Mountain
The Devil's Postpile

The Devil's Postpile is a columnar basalt structure. It was near the bottom of a deep flow of molten lava where it was well insulated and cooled slowly. While it cooled it contracted, and in contracting tore into individual columns. The slow rate of cooling determined the approx. 2 foot diameter of the columns, and the homogeneity determined the exact shape of the individual column. The process of shrinkage and cooling strives to minimize surface area, the hexagon being the ideal shape. However because cooling rate varied across the temperature scalar field, convex polygons of varying order occurred.

Most of the lava flow was eventually eroded away by glaciers that polished the top ends en passant.

Devil's Postpile 2
Petrified spaghetti - dipped in boiling water for 20 seconds before hardening.