Report on Nyiragongo (DR Congo) — 9 January-15 January 2002
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 9 January-15 January 2002
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2002. Report on Nyiragongo (DR Congo). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 9 January-15 January 2002. Smithsonian Institution and US Geological Survey.
1.52°S, 29.25°E; summit elev. 3470 m
All times are local (unless otherwise noted)
18 January Update
The following information is based on preliminary reports from various government and news agencies that were received during the ongoing crisis. An eruption began at Nyiragongo on 17 January and, according to news reports, as of 18 January lava flows had destroyed parts of 14 villages and 45 people had been killed. Some reports state that the eruption began at 0500 local time. Other reports state that probably around mid-day, fissures N of the Goma Airport opened and lava flowed from them at an estimated 2-3 m/min (1.2-1.8 km/hour) towards the town of Goma, ~10 km S of the volcano. Eruptions occurred on the volcano's S and E flanks. By late afternoon, at least one flow had advanced into Goma. At this time tremor with 5-second durations accompanied the lava flows about every 10 minutes. Gas stations exploded as the flows advanced through Goma, cutting a reported 35-70 m swath through the town on its way to Lake Kivu. In places, the lava flows were 2 meters high and 30 m wide.
The lava flows damaged 14 villages as they destroyed everything in their paths including, buildings, homes, and the port in Goma. The population of Goma (~400,000 people) and surrounding areas evacuated with some moving W on the road toward the town of Sake, while the majority of the population reportedly moved E towards Rwanda to the town of Gisenyi. According to news reports, United Nations officials reported that 45 people had been killed by the eruption as of 18 January. A Goma resident stated that by the morning of 18 January tremor had died down to "about one every 40 seconds to one an hour." Also, lava continued to flow, but was no longer a threat to the road linking Goma with Rwanda.
Geologic Background. One of Africa's most notable volcanoes, Nyiragongo contained a lava lake in its deep summit crater that was active for half a century before draining catastrophically through its outer flanks in 1977. In contrast to the low profile of its neighboring shield volcano, Nyamuragira, 3470-m-high Nyiragongo displays the steep slopes of a stratovolcano. Benches in the steep-walled, 1.2-km-wide summit crater mark levels of former lava lakes, which have been observed since the late-19th century. Two older stratovolcanoes, Baruta and Shaheru, are partially overlapped by Nyiragongo on the north and south. About 100 parasitic cones are located primarily along radial fissures south of Shaheru, east of the summit, and along a NE-SW zone extending as far as Lake Kivu. Many cones are buried by voluminous lava flows that extend long distances down the flanks, which is characterized by the eruption of foiditic rocks. The extremely fluid 1977 lava flows caused many fatalities, as did lava flows that inundated portions of the major city of Goma in January 2002.