McNutt, of the Alaska Volcano Observatory, had observed similar sparks during a 2006 eruption of Alaska's Augustine Volcano. The Redoubt Volcano data confirms the lightning's existence, he said.

"Shield volcanoes are almost exclusively basalt, a type of lava that is very fluid when erupted," Oregon State University explains. That gives these volcanoes their distinctive sloping sides.

While some volcanoes in India remain active, others have become dormant or extinct over millions of years. This article provides a detailed overview of India's volcanoes, their types, and their ...