Enquiry
Question 3
Answer:
What are the trends in frequency and impact
over time (Park Model)?
Visit the EM-DAT website and collect a
selection of maps and graphs related to tectonic hazards. Describe the
patterns.
Why do people live in tectonic areas?
What are the specific impacts of a range of
tectonic hazards at a range of scales and at locations in countries
at different stages of development?
Create a range of detailed case studies, they must be a variety in the
different stages of development.
For example: -
Level economic
development
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MEDC
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NIC
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LEDC
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Volcano
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Mount Saint
Helens
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Mount Pinatubo
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Montserrat
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Earthquake
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North Ridge
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Sichuan
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Haiti
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Tsunami
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Japan
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Boxing day
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Boxing day
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Use simple tables to classify impact into physical/economic/social plus
long and short term.
Use the Parks model to draw superimposed profiles of differing
impacts from earthquakes, tsunami and volcanoes
Use the following as a starting point for your research:
Haiti: Haiti a study of vunerability
New Zealand 2010 and 2011 : Tectonic Hazards in New
Zealand
China: China Earthquake
Japan Tsunami: The Japanese Earthquake
and Tsunami and Geofactsheet
Indian Ocean: Asian Tsunami and Analysis of Response
Montserrat: Volcanic Eruptions
Homework:
Read and add notes from the following in the correct enquiry question section.
http://geographyalevelslc.files.wordpress.com/2012/09/a133-earthquake.pdf
The response curve is a curve graphically exhibiting the magnitude of the response of a sensitive device to a varying stimulus (http://www.merriam-webster.com/dictionary/response%20curve)
As you can see the economic damage has
the following images above have been collected from (http://www.emdat.be/disaster-trends)
These shows the difference in economic cost over a variety of natural disasters such as Earthquakes, Volcanoes and Tsunami's in different regions all over the world.
These shows the difference in economic cost over a variety of natural disasters such as Earthquakes, Volcanoes and Tsunami's in different regions all over the world.
The pattern of the image above shows the average annual damages that have been caused by natural disasters from 1990-2012. This graph shows firstly that Americas have the most meteorological hazards than Asia and Europe and this
'Physical Processes do not become hazardous until they affect people through death and/or destruction' (http://internationalgeographer.files.wordpress.com/2013/06/advantages-of-living-in-a-volcanic-area-iceland.pdf)
Iceland lies on a constructive plate boundary between North America and Europe which is estimated to be moving at 2cm per year, meaning that volcanic eruptions and earthquakes occur. This can also lead to a unusual hazard called a 'Jokulhlaup'. This occurs when there is a volcanic eruption under an ice cap, the heat melts the ice, water then builds up and eventually bursts causing floods.
- 300,000 people live and work in Iceland
- DPR per capita of Iceland is similar to UK in 2004
Geothermal Heating
In 1970 only 43% of homes were heated by geothermal energy. By 2005 this figure reached 89% and is expected to rise to 92% in the future. Water from hot springs have been piped to homes in Reykjavik district heating service began operating. There are now over 2,200 km of pipe around the capacity the government sells hot water and industries and avoids importing expensive oil.
Tourism and Recreation
Spectacular Scenery, Basaltic cliffs, Waterfalls, Gorges, Rifts and grabens.
Sights attract many people each year
Risk= Frequency or Magnitude of Hazard x Level of Vulnerability
Capacity of Population to Cope
Park's Model
Montserrat Volcanic Eruptions 1995 – 1998
Before July 18, 1995 the 11,000 islanders of the British
colony of Montserrat in the Caribbean had liv3ed in one of the most beautiful
places on earth.
The Soufriere Hills volcano is situated above a destructive plate margin, or subduction zone. Oceanic crust from the North American plate is sinking under the Caribbean plate, forming a Antilles volcanic island arc.
The Soufriere Hills volcano is situated above a destructive plate margin, or subduction zone. Oceanic crust from the North American plate is sinking under the Caribbean plate, forming a Antilles volcanic island arc.
Main Hazards
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Phenomena
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Cause
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Hazard/Threat/Effect
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Pyroclastic flow – rapid avalanche of hot ash, gas and rocks moving
at 100mph with temperatures around 400C
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Collapse of the outer hardened dome exposes the hot lava inside.
Explosion occurs either horizontally or in a vertical column of ash which
then collapses and flows down the sides of the volcano.
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Incineration of any organic material, eg vegetation. Loss of life 19
people 26/6/97.
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Lahar – rapidly moving slutty of ash and water and other debris
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Heavy rainfall often from tropical storms or hurricanes mixes with
loose ash on volcanic slopes
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Burial and destruction of properties, vegetation and crops. Plymouth
gradually being buried
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Ash and tephra fall – particles from 1mm to 10cm of shattered rock
and hot lava fragments including pumice
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Violence of eruption shatters lava and rock into small particles.
Eruption clouds can reach 40,000 feet
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Day can become night under heavy rain fall
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Earthquakes
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Movement of magma inside the volcano
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Noticeable but no threat to structures
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Volcanic gases – carbon dioxide and sulphur dioxide
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Released from magma
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Poisons plants and animals
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An extensive seismograph network was established around the
volcano to measure earthquake strength and depth.
A satellite location GPS was also used to check ground movements.
A satellite location GPS was also used to check ground movements.
Effects
Plymouth contained all the main services – hospitals, banks,
schools, government and many private businesses
Collapse of the tourist and rice-processing industries
Unemployment has risen from 50% to 70%
70% rise in rent accommodation
skills shortage as people left
Collapse of the tourist and rice-processing industries
Unemployment has risen from 50% to 70%
70% rise in rent accommodation
skills shortage as people left
Haiti Earthquake 2010-
12th January 2010 an earthquake measuring 7 on the Richter scale of magnitude struck the country of Haiti, killing over 200,000.
Earthquake struck at 4:53pm. Its epicenter was 25jm south west of Port-au-Prince itself but was still affected.
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Figures
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Details
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Magnitude 7
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|
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Mercalli scale of earthquake intensity level 9
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|
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65km rupture
|
|
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52 aftershocks
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|
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230,000 deaths
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Due to earthquake or immediate aftermath
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6,9000 deaths
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November 2011, the number that died from the cholera epidemic that
followed the earthquake
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2.5 million homeless
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Living in tented camps
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60% infrastructure destroyed.
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Around Port-au-Prince
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70% buildings collapsed
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4,000 amputees
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Estimate of how many earthquake survivors lost limbs
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4,000 prisoners
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Escaped prison civile when destroyed
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$8billion
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Cost of damages and losses
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New Zealand - Tectonic Hazards
This lies between the Australian plate boundary and pacific plate boundary.
The pacific plate is being subducted along the east coast at a steep angle, underneath the relatively light continental crust of the Australian Plate. This is dragging the East Cape southwards, creating a rift zone further west, known as the Taupo Volcanic Zone, the area of most volcanic activity in New Zealand. Subduction occurs at a rate of up to 6cm/year7
D
artfield Earthquake 4h September 2010.0
4:34 am - magnitude of 7.1 earthquake hit Canterbury, 40km west of Christchurch
4 days later there was a 5.1 shock that caused more damage to the already weakened buildings, and on boxing day tremors were sufficient to close the main shopping mall.
Lyttleton Aftershock 22nd February 201111:51am 5 km from Christchurch 6.3
Impacts182 dead, covering 15 nationalities. Second deadliest event after Hawke's Bay Earthquake in 1931. In the city centre there was subsidence caused by liquefaction as well as deformation after crustal fracture. 80% of water and sewage systems were destroyed.
Three types of Volcanoes can be found in New Zealand and these are;
Volcanic Fields - these are areas of gentle, low frequency eruptions, forming single volcanoes that never erupt again
Cone Volcanoes - can erupt successively over time, building up lava deposits into a cone
Caldera Volcanoes - most violent and when they occur they can create caldera's 10-25 km wide and deposit ash and pumice over large areas
Potential hazards
Ash falls, Pyroclastic flows, lava flows, lahars, landslides, volcanic gas emissions, Tsunamis, Hydrothermal eruptions and Electrical storms.
Monitoring of Volcanoes
Ground deformation - as magma moves upwards and forces itself into crevices
Chemical Analysis
Seismic Monitoring
Tsunami
Require a shallow offshore earthquake with a magnitude of 7.5 and with vertical displacement
New Zealand have experienced tsunami's created by large submarine or coastal landslides caused by earthquakes
Large Earthquakes may cause waves on a lake known as seiches that can flood low lying lakeside areas, as well as travelling down rivers and flooding downstream.
Landslides
Green lake - 13,000 BP - possibly worlds biggest landslide, rock slippage of 26hm2 due to collapse of 10km of southern hunter mountain
Falling mountain ranch avalanche - 1929 - 55 million m3 rock moved 4.5km down valley
Abbotsford - 1979 - Destroyed 63 houses in South Dunedin
Summit of mt cook - 1991 - 12 million of m3 rockslide lowering the summit by 10m created a 3.9 earthquake.
New Zealand experience many high frequency landslides this is due to;
it's location on an active plate boundary
Easily eroded young soft sedimentary rock
Steep slopes in mountainous areas
High rainfall, often in storms
Glacial Retreat.
Asian Tsunami 2002
The earthquake rated 9 on the Richter scale generated the Indian ocean tsunami as a result of subduction of the Indian plate under the sunda plate.
Tsunami’s transmit energy very efficiently, with relatively little loss over considerable distances, since the rate at which waves lose energy is inversely proportional to their wavelength.
The deeper the water, the quicker tsunami travel, so they tend to travel very quickly across the ocean basins at the speeds of 700/800 km/hr
The earthquake rated 9 on the Richter scale generated the Indian ocean tsunami as a result of subduction of the Indian plate under the sunda plate.
Tsunami’s transmit energy very efficiently, with relatively little loss over considerable distances, since the rate at which waves lose energy is inversely proportional to their wavelength.
The deeper the water, the quicker tsunami travel, so they tend to travel very quickly across the ocean basins at the speeds of 700/800 km/hr
Impacts
it decreased with increasing distance from the epicentre, waves were up to 10m high 4m in Thailand, Sri lanka and Somalia on the African coast.
damage and loss of life was most severe in Sumatra near the epicentre. The coast line sediments easily eroded and the return of the tsunami to the sea scoured huge volumes of sand, so that the land was now below sea level
it decreased with increasing distance from the epicentre, waves were up to 10m high 4m in Thailand, Sri lanka and Somalia on the African coast.
damage and loss of life was most severe in Sumatra near the epicentre. The coast line sediments easily eroded and the return of the tsunami to the sea scoured huge volumes of sand, so that the land was now below sea level
Environmental impacts was EL Nino warming during 1997-1998
Human impacts was waste water , dynamite fishing and general acidification of oceanic waters.
Human impacts was waste water , dynamite fishing and general acidification of oceanic waters.
We seem to be still missing a lot of this it needs to be done for Monday!
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