under the summit to a mile (2 kilometers) or less beneath, the study found. This matched the timeline the geologists had observed with other signs. The last time Mauna Loa erupted was in 1984. Most of the U.S. volcanoes that scientists consider to be ...

That happened two years ago with the world’s largest active volcano. About two months before Mauna Loa spewed rivers of glowing orange molten lava, geologists detected small earthquakes nearby and other signs, and they warned residents on the Big Island.

About two months before Maunaloa spewed lava, geologists detected small earthquakes nearby and other signals. Now a study of the volcano’s lava confirms that molten rock within Earth's crust was rising upward about 70 days before the eruption in late November 2022.