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Volcano Under the City

Program Overview


Volcano NOVA investigates the dangers of Nyiragongo volcano, located in a densely populated valley in the heart of Africa.

The program:

  • recounts Nyiragongo's 2002 eruption, which left more than 100 people dead and another 100,000 homeless.

  • describes two main types of volcanic eruptions: explosive, as seen at Mt. Saint Helens where lava shot up 25 kilometers, and effusive, as seen in Hawaii, where lava is very fluid and erupts wherever it can.

  • notes that Nyiragongo is an effusive volcano characterized by an extensive network of fissures—which now extend beneath the city of Goma—that can fill with magma and erupt.

  • points out that the volcano contains lava that has been clocked at speeds of almost 100 kilometers per hour, making it the fastest-moving lava on Earth.

  • outlines how scientists forecast volcanic eruptions through the use of seismology, land deformation, and geochemistry, which they measure with seismology readings, satellite imagery, and gas fume sampling.

  • relates another threat facing Goma—concentrations of deadly carbon dioxide gas at the bottom of Lake Kivu that could be released through earthquake or lava eruption from Nyiragongo.

  • shows people building homes in the path of a potential lava flow because they are unafraid of the volcano's dangers or unable to go elsewhere.

  • follows volcanologists as they descend into the volcano's crater to collect gas and lava samples.

  • describes the dangers scientists face as volcano walls begin to collapse, forcing the team to abandon its efforts.

  • follows the team as it returns to the crater to attempt a new lava collection method.

  • details how scientists examine gas and lava samples to gain information about the volcano's current state.

  • summarizes evidence showing a very active volcanic system that could quickly erupt stored magma, flood the city with lava in minutes, and release toxic gases from the nearby lake—all of which could lead to a catastrophic natural disaster.

Taping Rights: Can be used up to one year after the program is taped off the air.

Teacher's Guide
Volcano Under the City

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