Report on Langila (Papua New Guinea) — November 1981
Scientific Event Alert Network Bulletin, vol. 6, no. 11 (November 1981)
Managing Editor: Lindsay McClelland.
Langila (Papua New Guinea) Eruption column to 6-7 km altitude; nuées ardentes
Please cite this report as:
Global Volcanism Program, 1981. Report on Langila (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 6:11. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.SEAN198111-252010.
Papua New Guinea
5.525°S, 148.42°E; summit elev. 1330 m
All times are local (unless otherwise noted)
"Strong eruptive activity continued in November. The present eruptive episode is the most intense since October-November 1980 (05:10-11). Detailed observations were made by a volcanologist 17-26 November.
"Crater 2 produced a wide variety of activity. Vulcanian explosions rising to about 2 km were commonly observed. Frequency of explosions varied from minutes to hours, and periods of near-continuous (Strombolian) activity were also noted. Crater 2 glow was seen during the first half of the month, followed by apparently more intense activity including ejections of incandescent tephra occasionally rising to 0.5 km above the source. Commonly the larger Crater 2 explosions registered a seismic airwave. Rumbling and detonations from Crater 2 were heard throughout the month.
"Small nuées ardentes were produced by backfall of ejecta from some of the Crater 2 explosions. The largest of the nuées travelled about 2 km down the E flank. Periods of continuous harmonic tremor appeared to be related to resonance effects in the Crater 2 lava conduit. Continuous fluctuating glow, incandescent tephra ejections, and associated rumbling and booming sounds were noted from Crater 2 during some of the periods of harmonic tremor.
"Crater 3 activity may have declined during the month. Incandescent tephra ejections or crater glow were common during the first half of the month, but only occasionally observed later in November. Several large Vulcanian explosions were observed. One on 13 November was reported by a passing aircraft pilot as rising to about 6-7 km altitude, and having a columnar appearance. Crater 3 eruptions later in the month were often single events. Some were accompanied by loud detonations and others were soundless. Some of the soundless eruptions were registered seismically as large-amplitude, low-frequency events.
"The new lava flow from Crater 3 appeared to become inactive in mid-November. The flow rate was evidently low, as only a small volume of lava was extruded during the 2-week period of lava effusion."
Geologic Background. Langila, one of the most active volcanoes of New Britain, consists of a group of four small overlapping composite basaltic-andesitic cones on the lower eastern flank of the extinct Talawe volcano. Talawe is the highest volcano in the Cape Gloucester area of NW New Britain. A rectangular, 2.5-km-long crater is breached widely to the SE; Langila volcano was constructed NE of the breached crater of Talawe. An extensive lava field reaches the coast on the north and NE sides of Langila. Frequent mild-to-moderate explosive eruptions, sometimes accompanied by lava flows, have been recorded since the 19th century from three active craters at the summit of Langila. The youngest and smallest crater (no. 3 crater) was formed in 1960 and has a diameter of 150 m.
Information Contacts: P. Lowenstein and C. McKee, RVO.