Geography MidYear Flashcards
Plate tectonics theory - what was Wegner’s theory and what was his evidence?
Know at least 2
Alfred Wegner said that the countries were one joined together as a big land mass called Pangaea and then they split like a puzzle.
Similar pattern of rock layers on different continents is evidence that the rocks were once close together or joined
Similar fossils are found in different continents. They could not have crossed oceans so the land was joint together at some point
What are the names and locations of major plates?
Plates:
-Pacific plate
-North American plate
-Eurasian plate
-South American Plate
-African plate
-Indo-Australian Plate
-Cocos plate
-Juan de Fuca plate
-Nazca Plate
explain why earthquakes and volcanoes are often found at plate boundaries?
Its because of the movement of tectonic plates causing stress and pressure that builds up in the earths crust
What are convection currents and why are they important?
Convection currents are slow but extremely powerful movements of volcanic rock in the mantle, they are important because they can move the earths plates
explain how earthquakes are measured (Richter and Mercalli)
Ritcher-The Richter scale can be used to measure the magnitude (power) of a tremor using an instrument called a seismometer
Mercalli-The Mercalli scale rates an earthquake’s
intensity based on observations of the
damage on a scale of 1 to 12
Can I explain the impacts and responses from the Haiti Earthquake case study?
There were social, economic, political and environmental impacts for eg:
Social effects: quality of life, transport, homes, health and education
Economic effects: wealth, jobs, income, tax and businesses
Political effects: government decisions
Environmental effects: the natural world, water, land, soil, trees etc
Explain why the impacts of the Haiti were so bad
The government was also responsible because they didnt build housing which could whittstand an earthquake aswell as important building such as hospitals, government buildings and prisons werent built on high and safe ground, which meant if people needed help if they were injured they wouldnt be able to be helped by the hospital and the prisoners also run away and cause havvock.
explain the causes and impact of a tsunami in an example location
In the Indian ocean near to indonesia the Indo-Australian plate was subducting under the Eurasian plates but eventually the stress was released causing tsunami waves to spread in all directions affecting Indonesia, India, Sri Lanka, Thailand, Malaysia, Myanmar, Bangladesh, Maldives and Seychelles.
Explain how prediction, preparation and protection can reduce tectonic
hazards
Prediction-Geologists monitor by: GPS systems, gas samples, robotic spider to collect rock samples and check the temperature, scientists measure the thermal temperatures or the volcanic rock, seismographs measure tremors.
Protecting-fire resistant building materials, steel frames, earthquake proof features, open spaces, automatic window shutters.
Preparing-Practise earthquake drills (going underneath table or into open area) the right items such as: water, meds, food, phone, batteries, tent, clothing, and other essentials.
What is a superpower nation?
A superpower is a country with the ability to influence and project power across the world
What are the factors that make a country a superpower?
Resources, military strength, political power, size, economic strength, population and soft power
Who are the emerging superpowers?
MINT (Mexico, Indonesia, Nigeria, Turkey
What is the structure of the earth?
1st - Crust, 2nd - Mantle, 3rd - Outer core, 4th Inner core (centre of the earth)
What is a convergent plate boundary?
A convergent plate boundary is where two plates strike at eachother causing the oceanic plate to go underneath the continental plate creating earthquakes, volcanoes and deep trenches. This causes the magma of the mantle to rise making volcanoes erupt.
What is a divergent plate boundary?
When plate boundaries move away from each other causing a tear. This tear causes underwater earthquakes and volcanoes. Then the magma to rises to the surface and slowly cool down creating new land
What are the properties of each layer of the earth?
Crust:
-Thinnest Layer
-It is solid rock broken up into pieces called tectonic plates
Mantle:
-Thickest layer of the earth
-It is made of semi-molten solid rock that can flow
Outer core:
-Made of semi liquid iron
-Approxiametly 2300km thick
Inner core:
-The most inner part of the earth (centre of the earth)
-The rock is solid in the inner core due to the pressure
How do tsunamis form?
They are caused by a large and sudden displacement in the ocean for eg:earthquake or volcanic eruption creating waves that spread outwards in all directions
