Report on Ulawun (Papua New Guinea) — March 1993
Bulletin of the Global Volcanism Network, vol. 18, no. 3 (March 1993)
Managing Editor: Edward Venzke.
Ulawun (Papua New Guinea) Activity continues at low level
Please cite this report as:
Global Volcanism Program, 1993. Report on Ulawun (Papua New Guinea) (Venzke, E., ed.). Bulletin of the Global Volcanism Network, 18:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199303-252120
Papua New Guinea
5.05°S, 151.33°E; summit elev. 2334 m
All times are local (unless otherwise noted)
"Activity . . . continued at the low levels reported for February. White vapour emissions usually varied from weak to moderate but were more forceful 26-27 March. Weak glow was reported on the 8th.
"Seismic activity was at a low level throughout the month; no distinct B-type earthquakes were recorded. Both RSAM and routine manual amplitude readings indicate a gradual decline in tremor levels since mid-February. However, the level of tremor is still higher than before January's brief flurry of activity."
Geological Summary. The symmetrical basaltic-to-andesitic Ulawun stratovolcano is the highest volcano of the Bismarck arc, and one of Papua New Guinea's most frequently active. The volcano, also known as the Father, rises above the N coast of the island of New Britain across a low saddle NE of Bamus volcano, the South Son. The upper 1,000 m is unvegetated. A prominent E-W escarpment on the south may be the result of large-scale slumping. Satellitic cones occupy the NW and E flanks. A steep-walled valley cuts the NW side, and a flank lava-flow complex lies to the south of this valley. Historical eruptions date back to the beginning of the 18th century. Twentieth-century eruptions were mildly explosive until 1967, but after 1970 several larger eruptions produced lava flows and basaltic pyroclastic flows, greatly modifying the summit crater.
Information Contacts: H. Patia, R. Stewart, and C. McKee, RVO.