PVMBG reported that an increase in both deep and shallow volcanic earthquakes at Awu were recorded on 22 March and again during 10-15 April. Tiltmeter data from two stations recorded inflation during 1 March-16 April. The Alert Level was raised to 3 (on a scale of 1-4) at 1800 on 16 April and the public was warned to stay at least 5 km away from the crater’s center. PVMBG noted that elevated seismicity had been occurring periodically since July 2023.

Geological Summary. The massive Gunung Awu stratovolcano occupies the northern end of Great Sangihe Island, the largest of the Sangihe arc. Deep valleys that form passageways for lahars dissect the flanks of the volcano, which was constructed within a 4.5-km-wide caldera. Powerful explosive eruptions in 1711, 1812, 1856, 1892, and 1966 produced devastating pyroclastic flows and lahars that caused more than 8000 cumulative fatalities. Awu contained a summit crater lake that was 1 km wide and 172 m deep in 1922, but was largely ejected during the 1966 eruption.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)