Lightning plus volcanic ash makes glass
Boulder CO (SPX) Mar 06, 2015 - In their open-access paper for Geology, Kimberly Genareau and colleagues propose, for the first time, a mechanism for the generation of glass spherules in geologic deposits through the occurrence of volcanic lightning. The existence of fulgurites - glassy products formed in rocks and sediments struck by cloud-to-ground lightning - provide direct evidence that geologic materials can be melted via ... more

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