Geography Flashcards
Where are volcanoes most likely to be found
On the boundaries of tectonic plates or often on the coasts of continents or countries.
What occurs at a destructive volcanic margin
The less dense oceanic crust slips under the continental crust and the friction created melts the rock turning it into magma, which shoots upwards towards the surface.
What occurs at a constructive volcanic margin
The two plates move in opposite directions leaving a direct path to the surface for the magma beneath the crust. This lava then cools to form a gentle-sided ridge
What is ash fall
A product of a volcano which can cover more distance and be more destructive overall then lava due to its immense weight when in mass.
What is a shield volcano
A gentle-sided volcano which forms when lava seeps into the crust and then spreads over the landscape.
What is a composite volcano
A steep-sided volcano which forms when the lava shoots out the crater and then solidifies on the slopes of the mountain.
What is a caldera
A volcano which has a large crater at the top after the volcano collapsed on itself during a violent eruption.
What is are intrusive and extrusive igneous rocks.
+intrusive igneous rock is formed when magma inside the volcano cools in the magma chamber, creating crystals.
+ extrusive igneous rock is formed when lava cools quickly on the surface after an eruption.
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How can volcanic eruptions be anticipated.
+ the surface becomes heated as the rising magma comes into contact with it (heat-seeking cameras)
+ earthquakes occur due to the amount of lava moving beneath the surface (seismometers)
+ bulges and swells appear as magma bubbles (tilt meters to see if slope has changed)
+ steam comes out the volcano as the magma bubbles
Why do people live in volcanic areas
+ fertile land
+ increased tourism
+ geothermal energy
+ valuable metals are produced by volcanoes
What are crude birth rate and crude death rate
+ Crude birth rate is the babies born in year per thousand population
+ Crude death rate is deaths each year per thousand population.
What are general fertility and infant mortality
+ General fertility is the annual live births per thousand women
+ Infant mortality is the death of under one year olds each year per thousand live births
What are life expectancy and dependancy ratio
+ life expectancy is the average lifespan of a population
+ dependancy ratio is calculation based on children/economically active.
What are population census and natural increase
+ population increase is the total count of people in a certain area
+ natural increase is the birth rate minus the death rate
What is a human population density factor
A factor that makes a population either high or low that is man-made such as government stability.
What is a physical population factor
A factor that makes a population density high or low that is determined by a country’s physical features such as relief.
What are some human factors for a high or low population density
+ high: good job opportunities in booming industries, stable government and people like to live near social groups.
+ low: unstable government, limited job opportunities or they are at war.
16 and understand are known as
The young dependants
16-65 are known as the…
Economically active
65+ are known as the…
Old dependants
What side are females on the population pyramid and what side are males
Females= right Males= left
What does it mean if a population pyramid has a sloping triangular shape
+ High birth rate
+ low life expectancy
+ high death rate
What does it mean if a population pyramid has a pyramidal shape
+ High birth rate
+ Fall in death rate
+ increasing life expectancy
What does it mean if a population pyramid has an rectangular shape that curves off at the top
+ declining birth rate
+ low death rate
+ high life expectancy
What does it mean if a population pyramid has an oval shape
+ low birth rate
+ low death rate
+ very long life expectancy
What is an ELDC
An economically less developed country
What is an EMDC
An economically more developed country
What are the effects of an ageing population
+ Increased number of economically active
+ more pressure on workers to provide for young dependants
+ more money spent on elderly healthcare instead of education and other important sectors