Tectonics case studies: E15, Nepal 2015, SAFL, Indian Ocean Tsunami, Philippines

Nepal 2015: Speed of the Indian plate moving north

45mm per year

Examples of Intraplate Earthquakes/faultlines

New Madrid seismic zones on the Mississippi

Examples of Mafic lava

Forming at constructive plate boundaries eg Iceland (pillow lava) - fissure volcano. Pretty pure lava that is low viscosity

Examples of andesitic lava

Lascar volcano in Chile - Strata Volcano. It's on a destructive boundary and contains silicates, meaning it is more explosive

Boxing Day 2004: Location of earthquake hypocentre

Around 250km off the Western coast of Northern Sumatra in the Indian Ocean
At a depth of 30km below sea level

E15: Population density

No-one lives there except for farmers
Only 450 people evacuated in a 100-mile radius

E15: primary impacts

Ash clouds were released and spread south across Europe
Lava flows

E15: secondary impacts

79% of Icelands sheep were killed from fluoride poisoning
Jokullhaup flooded the surrounding 30 mile area

E15: Ash clouds

Flights restrictions were brought in due to fears that particles could shut engines down
107,000 flights were cancelled over an 8 day period

E15 plate boundary

Iceland lies on a constructive plate boundary (Mid-Atlantic ridge fault line)
This allows magma to move up to the surface

E15: Impact on trade

Imports of fish and fruit at Heathrow started to rot
Kenya lost £24 million from fresh flower exports
The UK was unable to ship car parts to Japan, costing the economy £100 million

E15: Impacts on airports

Ash clouds costed UK airports over 1 billion billion pounds
Over 150,000 Britons were stranded abroad

E15: People and tourism

4000 visitors a day visited the volcano
2 Icelanders died when they got lost in the area

E15: Local responses

Locals received texts telling them to evacuate
Workers smashed holes in the main coastal highway to allow water to escape

E15: Global responses - citizens

Royal Navy ships were drafted to help people stranded abroad
Social media was used to organise ways to return home - Globalisation

E15: Global responses - business

5000 people were laid off in Kenya due to lack of profit
The Eurostat benefitted as people were unable to take flights
Tesco initiated emergency plans to fly produce into Spain

Nepal 2015: Moment magnitude

7.8

Nepal 2015: characteristics of hypocentre

Shallow depth: 10-15km per surface

Nepal 2015: Total population and most densely populated area

28 million people in Nepal
The Katmandu Valley has the highest population density and was one of the hardest hit areas

Nepal 2015: Infrastructure planning

60% of Nepals buildings were not deemed EQ proof
This is due to Nepal's rapid development and urbanisation

Nepal 2015: Impact on rural areas

Many villages were completely buried under rubble - death toll uncertain
Supplies arrived by helicopter due to roads being blocked off by landslides
Over 1000 people died form lack of food and fresh water

Nepal 2015: Impact on urban areas

3.5 million people left homeless, leading to deaths of exposure
8,800 people killed from collapsing buildings
Typhus outbreak infected 240 people
Severe lack of food, water and electricity

Nepal 2015 Immediate Responses

The Nepalese army was sent to stricken areas
The Red Cross was deployed from other countries to evacuate the wounded
Scientists used satellites to map out the damaged area
Within hours, India had responded with military rescue and relief

Nepal 2015: Long term responses

$160 million pledged to repair 1000 historic monuments
The UN pledged $4.4 billion to aid with reconstruction of houses
All building built after reconstruction were built to withstand earthquakes

Examples of constructive plate boundaries

Mid Atlantic Ridge, Iceland
Rift Valley, Africa

Example of a destructive plate boundary

The Andes, South America

Example of a conservative plate boundary

San Andreas Fault in California

Example of a collision boundary

Himalayas, Asia

Examples of hotspots

Yellowstone and Hawaii

Examples of lots of wider volcanic impacts (Pinatubo)

Pinatubo 1991 had pyroclastic flows, huge ash clouds, climatic change worldwide, no sunlight in the Philippines for 2 days

Example of a tsunami

Boxing Day 2004 - 275,000 people died, caused by a shift in the plate under the Indian Ocean (Indo Australian and Eurasian plate)

Japan 2011: Why was impact reduced across the mainland?

Wave refraction from islands meant that waves heading south from the epicentre took nearly a day to reach other land masses

Japan 2011: Background info

Epicentre: 130km East of Sendai

Focus depth: 29km

Magnitude: 9.0

Plate movement: subduction - Pacific plate under Okhotsk plate

Japan 2011: Social impacts

-15,000 deaths

-122,000 homes destroyed

-4.4 million homes lost electricity supplies

Japan 2011: economic impacts

-$300 billion to the Japanese economy

-Large scale infrastructure damage (eg. to ports)

Japan 2011: Environmental impacts

-Fukushima plant released high levels of radiation (partly why public perception is negative)

-Flooding destroyed 21 hectares of farmland

Chile tsunami: background info

Date: Feb 2010

Epicentre: 3km off Pelluhue coast

Focus depth: 35km

Magnitude: 8.8

Plate movement: Subduction - Nazca plate beneath South American plate

Chile tsunami: Who was killed?

Most fatalities were tourists camping in low-level coastal areas

Local residents were aware that a tsunami was possible so evacuated to higher ground

Chile tsunami: Social impacts

Over 520 fatalities

Shortages of food, water and fuel

-led to widespread looting in Concepción

Chile tsunami: Economic impacts

Cost: $30 billion

Talcahuano Port badly damaged: fishing and tourism industries faced decline

Food prices tripled in some places

Chile tsunami: Environmental impacts

Debris from collapsed buildings was dumped into wetlands

Pipe damage: unprocessed sewage was released into the Biobio river

Boxing Day 2004: Moment magnitude of the Indian earthquake

9.0

Boxing Day 2004: Seafloor rise

The Indian Earthquake resulted in a seafloor rise of several metres, displacing around 30km3 of water

Boxing Day 2004: Warnings

There were no warning systems in the Indian Ocean at the time, meaning that nearly all the victims were taken by surprise

Boxing Day 2004: Impacts

14 countries suffered fatalities

Tourists were killed in the disaster

Many countries suffered losses in their fishing and tourism industries

Coastline ecosystems (mangrove swamps) were uprooted by excess water

Boxing Day 2004: Economic impacts

Cost: $10 billion

Jetties and fishing fleets washed away, causing the industry to decline

Boxing Day 2004: Environmental impacts

Damage to coral reefs in the seas around the Maldives

Coastal mangrove forests flattened

Freshwater supplies contaminated with sea water

What is the Ring of Fire?

A tectonic belt of volcanoes and earthquakes about 40,000km long and 500km wide. It surrounds most of the Pacific Ocean. It has existed for more than 35 million years.

Names of the seven major tectonic plates

African
Antarctic
Eurasian
Indo-Australian
North American
Pacific
South American