Deck 5a - Tectonics: Mt.Nyiragongo, DRC Flashcards
What year was the Mount Nyiragongo eruption?
2002
What time did the Mount Nyiragongo eruption occur?
9:30am
What hazards were caused by the Mount Nyiragongo eruption?
Lava flow, ash, gases
What type of plate boundary is Mount Nyiragongo on and which tectonic plates are involved?
Constructive boundary that forms part of the East African Rift Valley. The African plate (also known as the Nubian Plate) in the west is splitting from the Somali plate in the east.
What type of volcano is Mount Nyiragongo?
Composite
What sort of magma does Mount Nyiragongo produce and what sort of eruptions does this lead to? Why?
Mafic/basaltic because it is located on a constructive plate margin meaning as the Nubian and Somali plates are pulled apart magma rises to to surface in between. As such the magma has not had time to evolve producing a mafic magma. This results in effusive eruptions with lava with a low viscosity as gas is able to escape readily.
How frequently does Mount Nyiragongo erupt?
(FREQUENCY)
34 times since 1882 averaging approximately once every 30 years.
What was the VEI of the Mount Nyiragongo eruption?
(MAGNITUDE)
VEI = 1
What was the duration of the Mount Nyiragongo eruption?
(DURATION)
1 day, 17th January 2002
What signs were there before the Mount Nyiragongo eruption occurred?
(PREDICTABILITY)
Harmonic tremors were felt though were not acted on.
How quickly did the Mount Nyiragongo eruption occur?
(SPEED OF ONSET)
The lava travelled rapidly at 60km/hour leaving just 30 minutes until it reached Goma. Within a few hours of the eruption starting a 13km fissure had opened with 3 main vents.
What area did the Mount Nyiragongo eruption impact?
(AREAL EXTENT)
Covered 4.7 km2 including 80% of the city of Goma
What was the GNI of the DRC before the Mount Nyiragongo eruption?
(ECONOMIC vulnerability)
$190 per capita in 2002
What was the level of technology available in the DRC during the Mount Nyiragongo eruption?
(ECONOMIC vulnerability)
Limited technology, very small team of geologists
How educated were the DRC’s population about the risks of volcanic eruptions prior to the Mount Nyiragongo eruption?
(SOCIO-ECONOMIC vulnerability)
Primary and secondary education enrolment has remained a serious issue since the DRC gained independence in 1960 largely due to costs associated with attending such as access to competent schools, funds for supplies. Enrolment rate is 40% in primary and secondary schools and is lower in areas of conflict such as Goma.