Kilauea Volcano: Energy Equivalent of 5.3-Magnitude Earthquake Hits Summit

Hawaii's devastating volcano had a busy weekend of seismic activity.

After nearly two months of constant eruption, there’s still no sign of stopping for Hawaii’s devastating Kilauea volcano. From “standing waves” to “lava balls” and glittery green gemstones falling from the sky, the eruption on the Big Island has delivered plenty of surreal twists to the already catastrophic damage. Most recently, two massive explosions at the summit produced the energy equivalent of two 5.3-magnitude earthquakes.

The first major collapse of the volcano’s peak on Friday triggered a day’s worth of increasing earthquake activity that preceded Saturday’s explosion, which was roughly the same size, according to the Hawaiian Volcano Observatory on Sunday. Earthquakes above a 5.0 magnitude are rarer than their smaller counterparts and occur approximately 30,000 times a year, compared to the million annual minor earthquakes that are nearly imperceptible by humans. Anything in the “moderate” range, like these tremors, are usually felt but rarely cause damage.

Kilauea volcano on Hawaii's Big Island.

National Park Service

The most noticeable effect of this weekend’s seismic activity was the plume of smoke sent 2,000 feet into the air on Saturday. That, along with gas emissions and acid rain, has emerged from the fissure 8 lava “fountain,” a rapidly moving 1 kilometer-wide stream feeding into the ocean. Winds blowing steadily toward the equator have caused the fog of gases and smoke to move southwest across the island along with “Pele’s hair,” a term used by Hawaiian natives to describe strands of volcanic glass that rain down from the fountain.

Understandably, that haze of chemicals has prompted the Hawaii County Civil Defense to warn locals to stay away from the path of fissure 8 — from the summit of Kilauea to the ocean entry at Kapoho — and monitor fog and air-quality conditions to avoid exposure to harmful gases. Lava from Kilauea has destroyed nearly 650 homes in the Leilani Estates subdivision of Puna, affecting thousands of Hawaiians and bringing the total of land covered by lava to over 6,000 acres.

As a refresher, volcanoes cause earthquakes when the movement of magma puts immense pressure on the tectonic plates below. In Kilauea’s case, the crater has pushed magma into available cracks, creating intense shockwaves that cause even more fissures for lava to seep into. With every crack, an earthquake follows. The cylindrical shape of the crater emits sound that could help scientists predict further eruptions by listening for the changing “screams” that indicate the depth of magma.