Case Studies🇳🇵🇮🇸🇵🇭 Flashcards
How was the African Rift valley formed?
- Elevated heat flow from mantle caused pair of thermal ‘bulges’ in central Kenya and the African region in Ethiopia
- As bulges formed they strand fractured creating faults in continental crust
- Conventional currents in asthenosphere cause extensions of crust. As crust extends garbens (down dropped blocks) and horses (up thrown blocks)are formed
- As rift continues to extend parts of crust become thin enough for oceanic type basalts to be erupted ➡️ new oceanic crust
- African crust will split in 2 forming the Nubian and Somalian plate
Where is the San Andreas fault line?
. In California from Salton Sea in south to cape Mendocino in North
. Lies in extreme western part of North America passing through Pacific Ocean in vicinity of San Francisco
Which 2 plates cause the San Andreas fault?
North American and Pacific plate
What could be some potential effects of an earthquake at the San Andreas fault line?
- Many houses destroyed
- Infrastructure damaged as close to fault line
- Roads + communication lines destroyed ➡️ Rapid Transit System
- Landslides+ wildfires
What happened at the 1906 earthquake at the San Andreas fault line?
- 3000 + people killed
- Damaged 28,000 buildings
- 225,000 made homeless
. Magnitude of 7.8
What are some of the features of Mauna Loa - shield volcano?
. Erupts once every year
. Located in United States
. Damage came to $1.5 million
. Evacuation zones put in place
What are some of the features of Yellowstone - super volcano?
. X 1000 bigger than Mt St Helens in 1980
. Caldera formed 55Km x 80 km wide
. Could kill 100000 people instantly
. Emergency kits could be installed
When did Eyjafjallaökull happen in Iceland?
In April 2010 ➡️ Impactes most of Europe in some way
Where is Eyjafjallaökull located?
. In Iceland along constructive plate margin between North American and Eurasian plates moving apart
What are the associated hazards of Eyjafjallaökull?
. Drop in temperature
. Rift valley formation
. Shield volcanoes
. Lava flow like a tricle
. Gentle earthquakes
. Ash produced
What were some of the primary effects of Eyjafjallaökull?
. Ash released ➡️ 5000 farmers had to be evacuated near volcano+ roads shut - social
. No fly zone imposed across Europe ➡️ losing £130 million a day for airlines - economic
. Water contaminated ➡️ high concentrations of fluoride mixed with water - deadly effects - environmental
. Ash cloud blocked sun - environmental
What were some of the secondary effects of Eyjafjallaökull?
. Trains across Europe boomed ➡️ as planes shut down people got around by trains, more usage + more profit - economic
. Effects on Kenya ➡️ 20% of economy based on fresh veg ➡️ 50,000 farmers temporarily unemployed - social + economic
. International flights disrupted - economic
. Many sport fixtures cancelled due to no planes ➡️ 2010 Japanese motorcycle Grand Prix postpones - social
What were some of the immediate responses to Eyjafjallaökull?
. 17 million in aid donated from UK
. People evacuated from south to undeveloped north
. Temporary infrastructure built
. Exclusion zone created
What were some of the long term responses to Eyjafjallaökull?
. £41 million in long term aid to develop north
. Integrated structure for air traffic ➡️ 9 airspace blocks will replace 27 blocks
. Increase tourism in area ➡️ 2011 visitor centre was built
. Rebuilt river banks even higher than before ➡️ Icelandic government
What was the magnitude and depth of the Nepal 2015 earthquake?
. Magnitude of 7.9 on Richter Scale
. Depth of 15km