Electrified air melts and alters ash
Lightning bolts that flash and clash high above erupting volcanoes can forge flying ash into glass, new research finds. The mechanism could explain the origins of odd microscopic glass beads found embedded in ash deposits, the researchers report online February 27 in Geology.
A volcanic eruption can kick up electrically charged material into the atmosphere, sparking lightning bolts that heat the surrounding air to more than 3,000° Celsius — more than hot enough to melt any nearby airborne debris. When rocky material heats up and quickly cools off, it can transform into glass.
Volcanologist Kimberly Genareau of the University of Alabama in Tu