Geosphere Journal Entry

Geosphere Journal Entry

Nyamuragira Volcano Still Feisty (January 23, 2010)

The eruption of Nyamuragira volcano in the Democratic Republic of Congo continued this week. Thick clouds of toxic sulfur dioxide gas filled the air around the volcano. Ash showered down on Goma, while fiery lava flows blazed within 4 miles (7 kilometers) of a major road road connecting Goma and Sake. The volcano, one of a pair surrounding Goma, erupted in 2006 and more than forty times since 1885.

The volcano's twin Nyiragongo is also a threat to erupt. Last year, lava streamed from the volcano's summit crater. Nyiragongo erupted violently in 2002, pouring lava into densely-populated Goma. The eruption destroyed thousands of homes and killed dozens of people. More than 200,000 people were displaced by the eruption.

Nyamuragira is a gently-sloped shield volcano. By contrast, Nyiragongo is a steep-sloped, stratovolcano with an active lava lake in its summit crater. The twin volcanoes form part of a volcanic chain along the East African Rift Zone. Rising magma steadily pushes slabs of Earth's crust apart along a divergent plate boundary marked by the rift. As the plates spread further apart, the rift valleys get deeper and longer. Eventually, they could fill with ocean water as East Africa splits off from the rest of the continent.