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“The extent to which tectonic processes represent hazards depends on when and where they are experienced. Discuss”

Throughout this essay I will be discussing my view on the extent to which I think tectonic processes represent hazards depending on when and where they are experienced. My view is that the hazards caused by tectonic processes such as volcanoes and earthquakes are very much likely to have a bigger impact socially, environmentally and economically depending on where they had occurred and when.
In the next few paragraphs I will discuss how the factor ‘WHEN’ tectonic processes occur represents hazards. Firstly, the time of day will have a big impact on the hazard. If the hazard occurs during the morning or afternoon rush hour, then there will be more impacts socially than if the hazard was to occur in the evening. For example, the Haiti earthquake in 2010 struck at lunchtime, which meant the city Port-au-Prince was packed with people eating in restaurants, eating outside, in homes. Because of this many people died due to buildings collapsing which increased the impact of the hazard.

Secondly, the type of season the tectonic process occurred in will have a huge impact on the effects of the hazard. In the summer, far more people are likely to be outside than inside and abroad in a hot country than a cold one. This means that if a tectonic process like an earthquake struck, the coasts would bring the tide in and many tourists and travellers that were on the beach could be injured. If the season is in the winter, and a tectonic process struck, the impacts would be huge. This is because the high levels of rain and colder temperatures make it harder for short term responses (such as aid, food and water) to be delivered to those who need it, which can be the difference between life and death.
Thirdly, the position of the government at the time in which a tectonic process occurs can impact the hazard effects. For example, depending on whether the government was in a corrupt/poor or strong state would affect the amount of response needed or sent out. For example, as Haiti is in the less economically developed stage, it needed many countries to respond to the appeal for air. Haiti needed pledged funds and dispatched rescue and medical teams, engineers and support for those affected. If the government was in a strong and reliable state, then it would have an even faster response rate as it wouldn’t have to rely on other countries, which meant that the medical teams could have arrived to the injured quicker, and as a long term response the country would not have to be in high amounts of dept to other countries.

In the next few paragraphs I will discuss how the factors ‘WHERE’ tectonic processes occur represent hazards. To give an insight to where tectonic processes occur, it’s useful to know that fault lines are the guidelines we follow to know where hazards may occur; they are where tectonic plates slowly move towards or away from each other. This movement can have a lot of geographical effects, which vary depending on whether the plates move towards each other or away from each other: When plates move towards each other, they can push each other upwards, creating mountain ranges such as part of the Caribbean island’s Haiti and the Himalaya. One plate can also start sliding over the other plate, pushing the other plate down. The area in which this happens is called a subduction zone, this is defined as an area in which two plates collide.
Firstly, plates that collide when one is sliding over another, is usually the oceanic plate (the top of the ocean floor) and the continental plate (the top of which is mostly land which lies above sea level). When this happens, the oceanic plate is pushed down by the continental plate, forming a very deep trench relatively close to the shoreline. This oceanic plate's crust, which is slowly being pushed further downwards, is then melted by the heat from the mantle (a layer of extremely hot rock) and becomes magma (molten rock in the earth’s inner parts). Depending on how much silica this magma contains, the magma may or may not reach the surface. If it doesn't, it then cools off at the ocean floor, and a hazard is not formed dramatically. If it does, a volcano is formed, which can cause many devastating effects socially, environmentally and economically. Examples of these kinds of volcanoes are the volcanoes in the pacific ring of fire.
Secondly, plates can also move away from each other at fault lines. This is what happens at mid-oceanic ridges, where two tectonic plates move away from each other causing the crust of these plates to get thinner, to the point where the crust is no longer strong enough to withstand the pressure of the magma on the inside of the earth it then bursts which allows huge amounts of magma to constantly flow out of the ocean bed creating, a new landmass when it cools down. Most divergent plate boundaries are at the bottom of the oceans, therefore most volcanic activity is submarine, forming new seafloor. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed, for example, Iceland. From the 20th of March till the 23rd June 2010, the Eyjafjallajokull volcano had huge seismic activity which left devastating effects for not only the people on the island, but for the rest of the world too, as airports got closed due to the ash clouds blowing around the skies.
Where a volcano hazard has occurred can leave either devastating effects to an LEDC or not as big effects to an MEDC. The fault lines occur throughout the whole of the planet’s crusts, to which either LEDC’s or MEDC’s sit on. The Icelandic volcano was situated on a MEDC so the effects were controlled due to the high level of development. No one died from the volcano, but people who did die, did due starvation and medical issues caused by the volcano such as respiratory problems. This compares to the Montserrat volcano, by which is an LEDC and 19 people died and many people had to be evacuated, due to the fact the country is less developed.
Thirdly, tectonic activity can also cause earthquakes when a plate underground ‘snaps’ along the fault. This sudden release in energy causes huge seismic waves that make the ground shake. An example is Japan and the Tohoku earthquake. On March 11th 2011, an earthquake with a magnitude of 9 struck offshore of Japan, as the pacific plate dived beneath the Eurasian plate. The stress release was because of an earthquake 2 days before with a magnitude of 7.2 which triggered the 9 quake. The focus had a depth of 20 miles below the surface, and the shaking lasted for about 6 minutes. This earthquake had such a big impact on the bottom of the sea bed that it triggered a 10m tsunami towards the city.
Earthquakes that occur can be situated anywhere along the fault line, but like the volcanoes, the level of impact is affected by whether the country is LEDC or MEDC. Japan is an MEDC, and the whole of the country is highly developed to good standard, many sky scrapers and buildings were built in presentation of earthquakes, but not so many were built in order to prevent tsunami effects. If it wasn’t for the tsunami occurring, 125,000 buildings would not have been left damaged, and 10,901 lives would not have been lost. The earthquake in Haiti on the 12th January 2010 left devastating effects for the whole of the country. The earthquakes epicentre was 15km from the capital Port-au-prince, which is very shallow which meant that the released energy was concentrated on the capital. 3.5 million people were affected, and 222,570 people died and over 300,000 left injured. This was because of the poorly built building styles which could withstand the effects of a 7.7 magnitude earthquake. These statistics between the MEDC and LEDC‘s show that where a tectonic process occurs, clearly have an impact the country its situated.
Not all volcanic activity takes place along fault lines. Hotspots are not usually located on the ridges of tectonic plates, but above mantle plumes. This is where the convection currents of the Earth's mantle create hot material that rises until it reaches the crust. The temperature of the plume causes the crust to melt and can vent magma. Each volcano becomes dormant after a while and a new volcano is then formed as the plate shifts over the hotspot. The Hawaiian Islands were formed due to Hotspots. The impact of the hotspot causing the Hawaiian Islands was a good one, as it has made a great holiday destination and beautiful sights; therefore this hazard wasn’t a bad one.

To conclude, I think the extent to which tectonic processes represent hazards depends very much on when and where they are experienced. I think this because a hazard is defined as a danger or risk, and the danger caused to people or the environments are influenced on where the tectonic process occurred e.g. fault lines and when and what situation the country was in during the process, e.g. government state and time of day etc.