An aerial inspection of Pago on 10 December confirmed that lava continued to slowly flow from the volcano. The lava flow remained confined by the walls of Witori caldera. Variable amounts of steam was emitted from vents. Blue vapor, which was inferred to be juvenile volcanic gas, was emitted from the northwestern-most vent. Seismicity continued to be at background levels, and consisted of small volcano-tectonic earthquakes.

Geological Summary. The Witori caldera (5.5 x 7.5 km) on the northern coast of central New Britain contains the active Pago cone. The Buru caldera cuts the SW flank. The gently sloping outer flanks consist primarily of dacitic pyroclastic-flow and airfall deposits produced during a series of five major explosive eruptions from about 5,600 to 1,200 years ago, many of which may have been associated with caldera formation. The post-caldera Pago cone may have formed less than 350 years ago; it has grown to a height above the Witori caldera rim, and a series of ten dacitic lava flows from it covers much of the caldera floor. The youngest of these was erupted during 2002-2003 from vents extending from the summit nearly to the NW caldera wall.

Source: Rabaul Volcano Observatory (RVO) via the Darwin Volcanic Ash Advisory Center