USGS HVO lowers alert level after volcanic activity decreases

With permission from Hawaiʻi Volcanoes National Park, a new temporary webcam has been installed on Cone Peak to provide better views of Kīlauea’s Southwest Rift Zone. USGS photo by M. Patrick.

HONOLULU (KHON2) — Following an eruption of intense activity in Kilauea’s upper East Rift Zone around 3:30 a.m. Tuesday, both earthquake frequency and ground deformation rates have decreased significantly.

For this reason, the USGS Hawaiian Volcano Observatory (HVO) is downgrading the volcano warning level for ground-based hazards from “WATCH” to “ADVISORY” and the Aviation Color Code from “ORANGE” to “YELLOW.”

This morning, earthquake activity was concentrated near Pauahi Crater in the upper East Rift Zone in Hawai’i Volcanoes National Park. Between 3:00 a.m. and 9:00 a.m., over 100 events were recorded, occurring at depths ranging from 1.0 to 3.0 kilometers below the surface. Most were less than magnitude 3, with the strongest reaching magnitude 3.4. The earthquake activity coincided with a significant change in ground deformation patterns, as indicated by the ESC tiltmeter.

The intensity of Tuesday morning’s earthquake swarm in the upper East Rift Zone was similar to that prior to the recent eruptions at Kilauea’s summit. The sudden inclinometer readings and concentrated earthquakes beneath Pauahi Crater strongly suggest magma intrusions that began at 3:30 a.m. The area around Pauahi Crater has a history of both intrusive and eruptive events. The episodic nature of this activity may indicate periods of intrusive activity over the past day. Additional seismic swarms could occur unexpectedly, potentially leading to further magma intrusions or lava eruptions.

For more information on volcano warning levels and aviation color codes, visit their website.