![]() Lavas have partially flown over areas covered during the 1989 eruption. west-east orientation (perpendicular to the Albertine Rift) about 10km east of the summit caldera. The 2011/2012 eruption, which began on is limited to a fissure system running in an approx. These appear to have been active in recent times. Several fault systems meet at Nyiragongo, (1) the main N-S fault, (2) a NW-SE trending system linking Nyamuragira to Nyiragongo, (3) a NE-SW trending fault system including the Rushayo chain of scoria cones (formed in 1948), and possibly (4) a further fault approximately parallel but west of the Rushayo chain over which lie the scoria cones of Muhuboli and Gituro (see Fig.2). Virunga volcanoes erupt extremely fluid low-silica high-alkaline lavas. Nyamuragira and nearby Nyiragongo mark the western end of the Virunga volcanic field and together with Visoke are the only volcanoes which have been historically active in the area. The wider geodynamical setting is discussed in more detail by Ebinger and Furman (Acta Vulcanol. The Virunga field belongs to the western branch of the East African Rift System and is located at the intersection between the N-S trending Albert Rift and Kamatembe and Bay of Bufumbira Rifts (see Fig.1). ![]() Nyamuragira volcano lies in the Virunga volcanic field which includes 8 volcanic edifices broadly trending in an E-W direction to the north of Lake Kivu. The Nyiragongo lava field is also identified with its flows from the 19 eruptions. Platz.įig.2 Map of lava flows from Nyamuragira volcano from 1938-2010 (darker flows are most recent). Inset Shows East African Rift System in the Area Surrounding Nyiragongo. Solid white lines: Bay of Bufumbira, Dashed white lines: Kamatembe Rift. Lava thrown above secondary crater complex of 2011/2012 eruptionįig.1 Annotated Satellite Image of Nyamuragira and its Surroundings. View over 2011 primary crater complex with main Nyamuragira ediface in background The paper also provides estimates of eruptive volumes for each eruption during the period, with average erupted volumes estimated at 72 million cubic meters, and a maximum of 200 million from the 1938-1940 eruption. 58, p.778-786 see Fig.2) cover over 40% of the flow field. Flows from 1938-2010 have been mapped by Smets et al. ![]() The flow field of Nyamuragira covers an area of 1100 square km. This, is a further factor accounting for the unusual length of some of the lava flows emplaced by the volcano. The slopes of Nyamuragira rise gradually, in contrast to the adjacent steep-sided Nyiragongo volcano to its SE, thus extending far from the summit region. The volcano has a steep-sided summit caldera with an approximate diameter of 2km, within which the main summit crater hosted a lava lake from 1921-1938. The flank eruptions are frequently accompanied by persistent lava fountaining, resulting in rapid enplacement of parasitic cones (of which more than 100 can be found), and lava flows which may extend for many kilometers due to the high fluidity of the potassium-rich low-silicate lava. Nyamuragira (or Nyamulagira) is frequently active, either within the summit caldera, or more problematically from varying locations on the flanks. Nyamuragira volcano (3058m) is a large basaltic shield volcano located about 15 km north of the city of Goma in the Democratic Republic of Congo.
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