The Restless Earth

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Case Study- The Andes

7000km long

300km wide

4000km av. height

Destructive Margin

S. American Plate and Nazca Plate

Venezuela, Columbia, Bolivia, Peru, Ecuador, Chile and Argentina 

Aconcagua in Argetina- Hightest peak

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Case Study- The Andes- Farming

Subsistence farming in rural Peru and Bolivia

Plots are small in Peru called Chacras

Steps are cut in hillside (terracing)- flat level to farm on

Unfertile soil made fertile by trapping rain with bunds giving rain time to infiltrate soil and add moisture and nutrients- increased productivity

Lower valley- cash crops rice, sugar, bananas and cotton

Middle zones- 750-1850m- hardy varieties of wheat corn and potatoes

Highest zones- plus 1850m llamas and Alpacas reared- meat, milk, clothes and transport

Llamas carry materials for irrigation in inhospitable and inaccessible areas

Can carry 25% of their body weight

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Case Study- The Andes- Tourism

The Inca Trail- The Ancient Highway- 45km treck- 3 routes

Historical, educational, recreation

250 species of orchids

Sacred city of the Incas- Machu Picchu

Rafting on Umbamba River

Thermal Springs in Aguas Calientas

Varied landscape, volcanoes, valleys, glaciers, mountains.

Birds, llamas, alpacas and orchids

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Case Study- The Andes- HEP

Hydro Electric Power- renewale energy contained in flowing water

Yuncan HEP project

2 dams across Paucartambo and Huanchon rivers in NE Lima

Volume of reservoir 63,000m2

Output per year 901GWh

Narrow valleys- easier and cheaper to dam

Steep slopes- The steeper relief encourages the rapid fall of water which is needed to ensure the generation of electicity

Snow capped mountains and high precipitation- snow melts in spring which will increse supply of water to the dam. High precipitation means there is enough water in the river all year

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Case Study- The Andes- Mining

Yanacocha gold mine- Northern Peru, 30km north of Cajamarca

251km2 open pit

Cajamarca has grown from 30,000 to 240,000 people

Latin America's largest and most profitable gold mine

Created 1,600 jobs

Geological conditions make it economical to exploit

Water has been polluted with cyanide and mercury making it brown

The locals traditional way of life destroyes

Fish are dying (trout)

Visual intrusion

Murcury spill in 2000

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Cae Study- Mount St Helens

Where: Cascade Mountains USA

When: 10th May 1980- 8:32am

Boundary:  Destructive, Juan de Fuca plate sinks benath N american plate

Friction- heat from core melts edge of oceanic plate into magma

expands, less dense, rises through convection forcing its way to earths surface

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Case Study- Mount St Helens- Effects

Primary Effects

  • NW flank blew outwards in explosion
  • ash cloud 15 miles into atmosphere in 15 mins
  • spirit lake filled with ash depth of 60m
  • Every tree in 250km2 destroyed
  • Mud cascaded down the mountain 50-80 miles/hr (due to melted snow by ash gases)
  • 57 people killed

Secondary effects

  • Economic loss in short term
  • Enviromental loss in short term
  • Ecosystem returned ash increases fertility and tourism increased (positive)
  • Media intrest after eruption brought tourists
  • Unemployment, fishing industries ceased trading as fish hatcheries destroyed
  • Cost off regenerating, replanting and repbuilding
  • Roads blocked
  • Houses destroyed
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Case Study- Mount St Helens- Responses

Immediate Responses

  • Volunteers- assisted S+R, look for friends and family
  • President- sent 2 million masks- when shortage
  • Emergency services/hospitals- medical treatment in nearby towns
  • Forestry service- Rescue operation- 170 peope, remove fallen timber
  • Military- mobalise helicopters, rescue survivors, clear ash 3 days later, use pumps to drain water and ash from spirit lake
  • County Sheriff- co-ordinates and manages

Long term responses

  • Forestry service- replant after removing timber
  • Construction companies, military and goverment- rebuild bridges buildings- to bring tourists back,
    • drainage systems, road to N reopened in 1990
  • Local authority- designed a national momumnet in 1982- Johnston Observatory 1997
    • Transform area $1.4million - 3mill visitors/yr
    • Tourist industry recovered
  • Scientists- research and monitor to prodect and prepare
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What is an earthquake?

An event of intense ground shaking due to the moevement of plates. Can happen at all plate boundaries- weak points or cracks are created called the focus

The focus emits shock waves in all directions. The point on the surface directly above the focus is worst effected- the epicenter

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What makes earthquakes have greater impacts?

Depth of focus- less energy lost

Type of plate boundary

Magnitude

Location of epicenter- denesly pop. area- near mountains, amplifies shock waves

Building design and construction- steel frames, deeep foundations

Time of day/week year

Public awareness and preperation

Wealth of country

Well organised goverment department- co-ordinate disaster management

Relief/ geology- loosley packed soil- liquefaction

Emergency serives

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Seismic waves

Surface waves- arrive later and cause the most damage- tansverse and longitudinal

Primary- travel very quickly through solids or liquids

Secondary- through rock and are slower than primary

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Case Study- Kobe Earthquake MEDC

When: 5:46am, 17th January 1995

Where: Kobe, Japan, SW, Awaji Island

Magnitude: 7.2

Tectonic setting: philippines plate (oceanic) shifted uneasily beneath the Eurasian plate (continental) along the Nojima fault line

Japan lies on the edge of the edge of the pacific plate (PRF) very tectonically active

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Case Study- Kobe Earthquake- Effects- MEDC

Primary Effects

  • Liquefaction where sediment is transformed into a liquid due to intense shaking- building collapse
  • 5,500 dead
  • 35,000 injuries
  • 80,000 building badly damaged
  • 67,000 buildings destroyed
  • 90% of port berths destroyed
  • 20km Hanshin Expressway destroyed

Secondary Effects

  • 300,000 homeless
  • 100 fires started in mins
  • No electricity for 900,000 people 
  • Panasonic and Mitsubishi closed losing 20,000 jobs and $11mill from lost trade
  • New jobs in construction
  • Economic recovery cost $220bill
  • Economic loss $147billion
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Case Study- Kobe Earthquake- Responses- MEDC

Immediate

  • Friends searched through rubble for survivors
  • Hospitals provided medical treatment- treating and operating in corridors
  • Emergency services co-ordinated S and R
  • *** Goverment $10bil contingency fund- relief effort- rebuilding, relief grants victims

Medium

  • Retailers 7-elen provided essential food and water
  • Motorola maintain telephone connections free of charge
  • The railways were repaired and 80% operational by July

Long Term

  • Hanshin Expressway was operational by Sept 1996, a year later the port was 80% operational
  • The *** Goverement set new building codes, all new buildings had to be retrofitted with flexible steel frames and rubber blocks to absorb shock.
  • Buildings also built further apart to avoid domino effect and spread of fires
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Case Study- Latur Earthquake- LEDC

Where: Latur District, Mahastra, Central W India

When: 03:56am, September 30th 1993

Magnitude: 6.4

Tectonic setting: Collision Margin, Indian and Eurasian Plates (continental) Himalayan mountains formed-pressure is released alonf fault line

Not at the edge of plate- unexpected 2% of EQs are intraplate

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Case Study- Latur Earthquake- Effects- LEDC

Primary

  • Main area effected- mahastra state. Epicentre at Kallari District. Latur. Primarilly affected the districts Latur and Osmanabas
  • Extensive damge to life and property
  • 20,000 killed
  • 30,000 people injured
  • 15,854 livestock killed
  • 52 villages destroyed, 27,000 houses, schools and infrastructure destroyed
  • 30,000 houses collasped

Secondary

  • Homelessness
  • Stress/grief- 60% pop. suffered from post- traumaticstress, 8-20% needed psychological help
  • People turned to drink and gambling 
  • Family break down- 138 widows, 340 orphans
  • Farming production ceased
  • Construction boom- av wage rates doubled
  • Cost of rebuilding $140mill
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Case Study- Latur Earthquake- Responses- LEDC

Immediate

  • Indian Army, State Reserve, police and central reserve carried out S+R
  • Dead bodies trapped under debris were removed
  • International Gov. and NGO's provided 120 trucks with tents, blankets, food, water, clothing and medical supplies
  • World Bank, Asain Development Bank, NOGs and Indian Gov. provided first aid and mediacal aid

Long Term 

  • Goverment formulated a rehabilitation policy within 6 months and order the construction of new houses in new village sited away from known fault lines
  • New homes were dome shaped and designed to be quake proof
  • Red cross constructed 3 rural hospitals as well as medical centres
  • Funds from Gov. and World Bank paid for new wells and cattle farmers
  • A new disaster management organisation established to improve prediction and preparation
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