Report on Witori (Papua New Guinea) — 13 August-19 August 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
13 August-19 August 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Witori (Papua New Guinea). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 13 August-19 August 2003. Smithsonian Institution and US Geological Survey.
Papua New Guinea
5.576°S, 150.516°E; summit elev. 724 m
All times are local (unless otherwise noted)
During 25 June to 14 August, volcanic and seismic activity remained at low levels at Pago. Small amounts of "fume" were released from the lower vents, with only trace amounts of SO2emissions in early August. A local tectonic earthquake on 9 August led to an increase in energy release and number of earthquakes recorded at one seismic station.
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)