Nyiragongo Volcano

Nyiragongo volcano (also spelled Niragongo), one of the world’s most beautiful and active volcanoes, is a large stratovolcano near Lake Kivu at the eastern border of DRCongo with Rwanda in the Virunga National Park.

It has a 1.2 km diameter summit caldera containing the world’s most active and largest lava lake.

Nyiragongo is infamous for its extremely fluid lava that runs as water when the lava lake drains. On January 17, 2002, Nyiragongo erupted and the lava lake drained from fissures on its western flanks. The city centre of the Goma town, the capital of the East Virunga province, had been destroyed by voluminous lava flows. 200,000 people were left homeless, adding to the human disaster caused by frequent civil wars.

Unfortunately, Lake Kivu has many possible sources for heat flux, the primary source of concern being Nyiragongo volcano. Nyiragongo was first studied for its permanent lava lake. Only about a half a dozen lava lakes have been discovered, and few have been studied at any depth. Nyiragongo was difficult for volcanologists to reach because of bureaucratic reasons, and political situations (Tazieff, 1994).

Nyiragongo volcano, An Evolving Rift System

If the rift system continues to evolve underneath Lake Kivu and nearby Nyiragongo volcano, there is the possibility that lava may again break out in the city of Goma, or worse yet, underneath Lake Kivu (Reed, 2002). Possible fissures associated with rifting would be more hazardous than any prior volcanic eruption if they cause rollover within the lake. It is important to realize that although Lake Kivu has not overturned recently, the chance of occurrence still exits. It is when even well-studied volcanoes depart from their expected behavior that hazards take place (Martinelli, 1991).

Nyiragongo, located in the Western branch of the Rift Valley near Lake Kivu and the Congolese-Rwandese border, is one of the world’s most active volcanoes. It is notorious for its lava lake and producing lateral eruptions with extremely fluid, fast-moving lava flows that repeatedly devastated areas around the volcano, such as the Goma desaster on January 2002, when a lava flow destroyed much of the city’s commercial center and promted 200,000 people to flee.

The large lava lake contained in its deep summit crater, now active again, became famous in the 1960’s and 70’s when volcanologists such as the Kraffts and Tazieff studied it. It had been active for half a century before it drained in one of the volcano’s recent most catastrophic eruptions in 1977: through openings in its outer flanks in 1977, a huge lava flow poured out and killed hundreds of people. A similar event happened again in January 2002, when lava flows from flank vents drained the lake and cut through Goma, reaching Lake Kivu.
In contrast to its neighbor volcano, Nyamuragira,- a typical, and very active shield volcano comparable with Mauna Loa,- the 3470-m-high Nyiragongo displays the steep slopes of a stratovolcano. Terraces inside 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 volcanoes, Baruta and Shaheru, are partially overlapped by Nyiragongo on the north and south and look like lateral cones. 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 of the volcano.