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natural hazards ((Other examples of natural hazard risks in an LIC include…
natural hazards
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Over 200,000 people died.
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The earthquake in 2005 in Kashmir, Pakistan.
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earthquakes
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Sometimes, because of friction, plates try to move and become stuck. Pressure builds up because the plates are still trying to move. When the pressure is released, it sends out huge amounts of energy causing the Earth's surface to shake violently.
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Earthquakes are found at all three plate boundaries: constructive, destructive and conservative plate boundaries.
The largest earthquake ever recorded was in Chile in 1960, which measured 9.5 on the Richter scale.
plate tectonics
The Earth has four main layers - the inner core, the outer core, the mantle and the crust.
The inner core is 5,500°C - extremely hot. It is a very dense solid made from iron and nickel.
The outer core is 2,000 km thick and is a liquid.
The mantle is semi-molten and about 3,000 km thick.
The crust is the rocky outer layer. It is thin compared to the other sections, approximately 5 to 70 km thick.
If the Earth was scaled down to the size of an apple, the crust would be about the thickness of the apple skin
plate margins
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subduction zone
re plate tectonic boundaries where two plates converge, and one plate is thrust beneath the other. This process results in geohazards, such as earthquakes and volcanoes
constructive
sometimes called a divergent plate margin, occurs when plates move apart. Volcanoes are formed as magma wells up to fill the gap, and eventually new crust is formed. An example of a constructive plate boundary is the mid-Atlantic Ridge.
destructive
is sometimes called a convergent or tensional plate margin. This occurs when oceanic and continental plates move together. The oceanic plate is forced under the lighter continental plate. Friction causes melting of the oceanic plate and may trigger earthquakes
conservative
, sometimes called a transform plate margin, occurs where plates slide past each other in opposite directions, or in the same direction but at different speeds. Friction is eventually overcome and the plates slip past in a sudden movement. The shockwaves created produce an earthquake .
Hazard risks - economic, social and environmental consequences
For each hazard event the risks, or probability, of a particular consequence occurring can vary greatly.
in a developing country, the death toll tends to be high but the short-term economic costs are often relatively low, whereas in a developed country, the death toll tends to be low but the short-term economic costs can be extremely high.
Developing countries can be slower to repair damage to roads and buildings. This can lead to a reduction in tourists and therefore a long-term loss of valuable income.
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