Report on Semeru (Indonesia) — April 1986
Scientific Event Alert Network Bulletin, vol. 11, no. 4 (April 1986)
Managing Editor: Lindsay McClelland.
Semeru (Indonesia) Normal small Vulcanian explosions continue
Please cite this report as:
Global Volcanism Program, 1986. Report on Semeru (Indonesia) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 11:4. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198604-263300.
8.108°S, 112.922°E; summit elev. 3657 m
All times are local (unless otherwise noted)
"Semeru continued to have several small Vulcanian explosions/hour during April. The maximum height of the eruption clouds was ~1 km above the summit. This represents the normal state of activity at Semeru."
Geologic Background. Semeru, the highest volcano on Java, and one of its most active, lies at the southern end of a volcanic massif extending north to the Tengger caldera. The steep-sided volcano, also referred to as Mahameru (Great Mountain), rises above coastal plains to the south. Gunung Semeru was constructed south of the overlapping Ajek-ajek and Jambangan calderas. A line of lake-filled maars was constructed along a N-S trend cutting through the summit, and cinder cones and lava domes occupy the eastern and NE flanks. Summit topography is complicated by the shifting of craters from NW to SE. Frequent 19th and 20th century eruptions were dominated by small-to-moderate explosions from the summit crater, with occasional lava flows and larger explosive eruptions accompanied by pyroclastic flows that have reached the lower flanks of the volcano.
Information Contacts: Olas, Suratman, Suparto, Kaswanda, and A. Sudradjat, VSI.