Topic 1: Hazardous Earth Flashcards
Lithosphere
Made up of the crust and the brittle upper mantle. It is the coolest of the earth’s layers
Asthenosphere
This is where the convection currents occur which heat up the lithosphere. The asthenosphere is made up of the lower mantle, outer core and the inner core.
Inner core
The inner core is solid and it is made of iron and nickel. The heat is caused by other radioactive elements which decay and release heat.
Outer core
The outer core is liquid and it is also made from iron and nickel
Mantle
The mantle is the largest section of the Earth and it is made of semi molten rock. The mantle is approximately two thirds of the Earth’s mass
Crust
The crust is made up of tectonic plates which are constantly moving. There are two types of crust which make up the land and the sea
Convection current
The stream of fluid moved by heat. Hot liquids rise, cool, and then fall back to the bottom.
Convergent
The oceanic crust sinks underneath the continental crust forming a trench and possible earthquakes
Divergent
The plates pull apart forming volcanoes. When the lava cools it forms more rock
Conservative
This is where the plates slide past each other. They are likely to get stuck and jolt which causes huge earthquakes. Do not have to be moving in different directions as they can move at different speeds
Primary impact
Things that happen immediately after a natural disaster. These effect people the most. For example, how many homes were destroyed
Secondary impact
Things that are effected later on. For example, how many people were made homeless
Hot spot
Plumes of magma rise to the surface. If there are any cracks in the crust, then a volcano will be formed
Magnitude
How strong the natural disaster was from 1-9. Dictates how much damage there is and how many people will feel it.
Shield volcano
A volcano formed through low viscosity lava, which spreads out very quickly like water on a table.
Composite volcano
A volcano made up of layers of cooled lava and cooled ash. This makes the volcano very tall
Collision
Where two pieces of continental crust collide then they cause a huge earthquake as neither can sink under the other
Plate tectonics
The crust is made up of plate tectonics that move as they are floating on top of the magma
Oceanic crust
A heavier crust which makes up the sea. Would sink under continental crust which is lighter
Continental crust
A lighter crust which makes up the land. It would rise over oceanic crust which is denser
Richter scale
Measures earthquakes by a logarithmic scale
Low viscosity
Lava that runs really quickly like water on a table
High viscosity
Lava that runs really slowly almost like treacle
Pyroclastic flow
Fast moving current of hot gas and volcanic matter.
Low air pressure
This is where air heats up, it expands and then starts to rise.
High air pressure
This is when the air in the atmosphere starts to cool and sink back down towards the crust.
The Gulf Stream
This is a warm ocean current that moves across the Atlantic Ocean towards the UK. It heats up the western coast
Global circulation model
This is the movement of the atmosphere and it is divided into three different cells above and below the equator.
The Hadley cell
This is one of the three cells in the global circulation model- it is the one nearest the equator.
The ITCZ
The inter tropical convergence zone is in the tropics between the two Hadley cells.
Greenhouse effect
The gases in the atmosphere trap heat from the sun and heat the atmosphere up like glass in a greenhouse. This lets heat in but it doesn’t let it back out.
Global warming
The warming of the Earth.
Japan’s preparation for earthquakes (a developed country)
Three parts:
Prediction: JMA and local governments monitor seismic activity. If an earthquake is detected, people are warned immediately
Preparation: High rise buildings have shock absorbers to reduce vibrations. Buildings reinforced with steel frames. Automatic alarms to alert workers and prevent injuries
Long-term planning: Disaster Prevention Day nationwide drill to practice evacuations. Schools carry out drills. People in coastal communities practice getting to higher ground.
Pakistan’s preparation for earthquakes (a developing country)
Three parts:
Prediction: Until recently there was very little monitoring of seismic activity, meaning earthquakes could strike without warning
Preparation: Pakistan doesn’t have access to building materials for stronger buildings because it is a developing country. Poor communication networks make it difficult to alert the population
Long-term planning: Poor remote settlements with no education program for earthquake. Very few roads and poor communications so planning evacuations is hard.
Japan - recent earthquakes
11th March 2011 North east Japan 9.0 on the Richter scale Triggered tsunami Japanese scientists predicted an earthquake but not one of this magnitude
Pakistan - recent earthquakes
8th October 2005
7.6 on Richter scale
Caused landslides, rockfalls and destruction
Despite seismic activity being monitored, the earthquake was unpredicted
Japan earthquake primary impacts
Thousands of buildings were damaged
Earthquake caused severe liquefaction, buildings sunk into ground
Pakistan earthquakes primary impacts
80, 000 deaths
Tens of thousands of people injured
Hundreds of thousands of buildings damaged or destroyed
3 million people made homeless
Water pipelines and electricity lines broken
Japan earthquake secondary impacts
Tsunami triggered which killed thousands of people
230, 000 people made homeless
Tsunami cut off power supplies to Fukushima nuclear power plant causing a meltdown
325km of railway tracks washed away
Pakistan earthquake secondary impacts
Landslides buried people and roads
Diarrhoea and other diseases spread due to lack of clean water
Freezing winter conditions after earthquake caused more casualties and meant rescue was harder
Japan earthquake short term relief
International aid and search and rescue teams brought in
Transport, power supplies and communications restored after a few weeks
Pakistan earthquake short term relief
Pakistani army slow to respond
Help from India was refused because of tensions between India and Pakistani
Tents, blankets and medical supplies distributed, although it took months to reach some areas
Japan earthquake long term planning
No collapsed buildings in Tokyo
Japanese authorities gave people time to get to higher ground
Pakistani earthquake long term planning
Fault lines in Himalayas poorly monitored which meant the Pakistani earthquake was unpredicted
Most buildings had been constructed from poor quality materials e.g. cement made from sand which crumbled during the earthquake
