Report on Witori (Papua New Guinea) — 4 July-10 July 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 4 July-10 July 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Witori (Papua New Guinea). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 4 July-10 July 2012. 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)
Based on analyses of satellite imagery, the Darwin VAAC reported that on 11 July an ash plume from Pago rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted over 275 km SW.
Geologic Background. The 5.5 x 7.5 km Witori caldera on the northern coast of central New Britain contains the young historically active cone of Pago. The Buru caldera cuts the SW flank of Witori volcano. The gently sloping outer flanks of Witori volcano consist primarily of dacitic pyroclastic-flow and airfall deposits produced during a series of five major explosive eruptions from about 5600 to 1200 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. Pago has grown to a height above that of 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.