"Explosive eruptive activity continued at Crater 2, and was stronger 2-6 September. Up to 12 explosions per day were recorded, and periods of strong volcanic tremor were produced by prolonged gas venting. Activity declined 8-11 September, but re-intensified on the 12th. Moderate activity persisted for the remainder of the month, including patchy and weak tremor and 1-9 explosions per day. Weak red glow was observed over Crater 2 on 25 and 29 September. Light to heavy ashfalls were common in coastal inhabited areas about 10 km to the NW and N."

[Richard Stoiber, Stanley Williams, and Chris McKee used a COSPEC to measure the rate of SO₂ emission from several volcanoes in Papua New Guinea during September (table 2). Plumes at and Manam were strong, and plume was small. Activity at Langila was weak 11 September, but had intensified during measurements the next day. The quiet-phase data were collected from the ground; all other data were acquired while flying under the plumes.]

Table 2. Rates of SO₂ emission at Bagana, Langila, Manam, and Ulawun, Papua New Guinea, September 1983. Airborne COSPEC data from R. Stoiber, S. Williams, and C. McKee.

Geological Summary. 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 E flank of the extinct Talawe volcano in the Cape Gloucester area of NW New Britain. A rectangular, 2.5-km-long crater is breached widely to the SE; Langila was constructed NE of the breached crater of Talawe. An extensive lava field reaches the coast on the N 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. The youngest and smallest crater (no. 3 crater) was formed in 1960 and has a diameter of 150 m.

Information Contacts: C. McKee, RVO; R. Stoiber and S. Williams, Dartmouth College.