Ulawun (Papua New Guinea) – Report for 31 July-6 August 2019 – NEW

RVO reported that during 1-2 August white-to-grayish vapor plumes rose from Ulawun?s summit crater and drifted NW. Incandescence from the summit crater was visible at night and jetting noises were audible for a short interval. RSAM values fluctuated but peaked at high levels. During the night of 2-3 August crater incandescence strengthened and roaring noises became louder around 0400. An eruption began between 0430 and 0500 on 3 August; booming noises commenced around 0445. By 0600 dense light-gray ash emissions were drifting NW, causing ashfall in areas downwind including Ulamona Mission. Ash emissions continued through the day and grew from light to dark gray with time. The eruption intensified at 1900 and a lava fountain rose more than 100 m above the crater rim. A Plinian ash plume rose 19 km and drifted W and SW, causing ashfall in areas downwind such as Navo and Kabaya, and as far as Kimbe Town. The Darwin VAAC reported that the ash plume expanded radially and reached the stratosphere, rising to 19.2 km (63,000 ft) a.s.l. The plume then detached and drifted S and then SE.

The Alert Level was raised to Stage 3 (the second highest level on a four-stage scale). The areas most affected by ash and scoria fall were between Navo (W) and Saltamana Estate (NW). Two classrooms at the Navo Primary School and a church in Navo collapsed from the weight of the ash and scoria; one of the classroom roofs had already partially collapsed during the 26 June eruption. Evacuees in tents as a result of the 26 June eruption reported damage. Rabaul town (E) also reported ashfall. Seismicity declined rapidly within two hours of the event, though continued to fluctuate at moderate levels. According to a news source flights in and out of Hoskins airport in Port Moresby were cancelled on 4 August due to tephra fall. The Alert Level was lowered to Stage 1. Small amounts of white and gray vapor were emitted from the summit crater during 4-6 August.

Sources: Darwin Volcanic Ash Advisory Centre (VAAC),Papua New Guinea Post-Courier Online,Rabaul Volcano Observatory (RVO),Radio New Zealand