WASHINGTON (AP) – Scientists don’t know exactly when a volcano is about to erupt, but sometimes they can pick up some signs.

This happened two years ago too world’s largest active volcano. About two months ago Mauna Loa It vomited rivers of glowing orange molten lava, geologists detected small earthquakes and other signs nearby and warned residents of Hawaii’s Big Island.

Now a study of the volcano’s lava confirms the timeline in which the molten rock below is in motion.

“Volcanoes are misleading because we can’t directly monitor what’s going on inside; we have to look for other signs,” said volcano expert Erik Klemetti Gonzalez of Denison University, who was not involved in the research.

The rising ground and increased earthquake activity near the volcano are caused by magma rising from lower levels of the Earth’s crust filling chambers beneath the volcano, said Kendra Lynn, a research geologist at the Hawaii Volcano Observatory and co-author of a new study. Nature Communication.

When the pressure was high enough, the magma broke through the brittle surface rocks and became lava, and the eruption began in late November 2022. Next, the researchers collected volcanic rock samples for analysis.

The chemical structure of certain crystals in the lava showed that large amounts of molten rock moved from about 1.9 miles (3 kilometers) to 3 miles (5 kilometers) below the summit to a mile (2 kilometers) below it about 70 days before the eruption. The study found that under or less. This matched the timeline geologists had observed with other signatures.

Mauna Loa last erupted in 1984. Most of the U.S. volcanoes that scientists consider active are located in Hawaii, Alaska and the West Coast.

Approximately 585 volcanoes are considered active worldwide.

Ben Andrews, who heads the global volcano program at the Smithsonian Institution and was not involved in the research, said scientists could not predict eruptions but could make a “guess”.

Andrews compared volcano forecasts to weather forecasts; gave information about the “possibilities” that an event would occur. Better data on the past behavior of specific volcanoes could help researchers fine-tune predictions of future activity, experts say.

(asterisk)We can look for similar patterns in the future and expect conditions to have a higher probability for an eruption to occur,” Klemetti Gonzalez said.

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