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Geologist examining a lava flow up close.

By Communications and Publishing 2010 (approx.)
View looking up to craggy rock cliff face covered in bright orange lichens, with a person perched on the face of the outcrop.
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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.

Sources/Usage

Used with permission.