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Geologist examining a lava flow up close.

2010 (approx.)

Detailed Description

USGS geologist Seth Burgess examining a Siberian Traps lava flow up close. The vertical cracks formed during cooling of the lava flow, dividing the original basaltic lava into hexagonally shaped columns of rock. The many horizontal cracks across the columns are likely also related to cooling of the flow. The orange patches on the rocks are lichens.


Used with permission.