On the other hand, the second disaster affects the cities more than the forests. It damages buildings, streets, and bridges and that will lead to human's death. These damages also will impacts the economy of the country. Moreover, the earthquakes may cause Tsunamis, if it happens in the
A hazard is a natural event that has the potential to effect both life and property. When looking at earthquakes there is one primary hazard which occurs and this is the shaking of the ground. In addition there are many secondary hazards such as landslides, fires, avalanches, liquefaction and tsunamis. There are many human factors to be discussed such as preparedness, development level, land use and education and many other contradicting factors such as the tectonic setting and the time of year. To show the view that the impact of earthquake hazards depends primarily on human factors, I will situate the essay around some seismic events that have previously occurred; Haiti in the Caribbean, 2010, Christchurch in New Zealand, 2011, Sichuan in China, 2008 and Indian Ocean, 2004.
They create huge media attention as the rate of change from what would have been considered as ‘normal’ conditions is very high, for example an earthquake can turn an entire city to ruins and kill hundreds of people in just minutes. They have a limited areal extent and usually have a low predictability. However improvements in science and technology are slowly increasing the predictability of the occurrence of these events but the impact it will have is more difficult to determine. Other examples of catastrophic hazards include tsunamis and volcanoes. Chronic hazards are less newsworthy than catastrophic hazards but because their effects are cumulative over time but the effect can be just as, if not more severe.
How to predict an volcanic eruption Ground Deformation Ground deformation is the change in shape that happens before during or after a volcanic eruption. This happens because the sides of the volcano change shape because the magma in many ways to measure the change of shape of the volcano, like leveling, triangulation and more recently using continuous Global Positioning System (CGPS). It is also possible to use lakes as large tilt meters. Tilt meters measure the tiny degrees of tilt or slope on land. This is one of the oldest methods of knowing when ground deformation was caused because of rising lava.
Analyse the factors that cause differences in the hazards posed by volcanoes around the world (40 Marks) A hazard is a potential situations that we, as a race, perceive as a threat to life, whether that be in respects to death, health or even economically. We perceive, from historical experiences and scientific study, that volcanoes pose a hazard to our life via periodic eruptions that take place. However, there is clear variability of the damage, or level of hazard, that these volcanic events cause. This can be down to a number of factors. For this, an analysis of the controlling factors must be made, such as the settlement of the area, the composition of the volcano and the economic status of the area that is affected.
Everyday day across the world, plate tectonics and their respective movements cause various seismic and volcanic hazards and a common idea is that the poorest people suffer the greatest from the impacts of these hazards in their LDCs. This, however, is only true in some cases as there are several other factors that affect how severely people are impacted by the hazards in both human and physical ways. I personally disagree with this view and this is due to several topics I have studied considering both human and physical factors. The first point I will make is based simply on the fact that volcanoes and earthquakes can have different hazards within them both primary and secondary which can have the same impacts no matter whether you are rich or poor, a tectonic hazard does not specifically target poorer people, it affects the area surrounding the cause. With a volcano you can have different types of hazard depending on the location is respect to constructive and destructive margins and also including hot spots, at a constructive margin or hot spot you find shield volcanoes with basaltic lava and these eruptions are common enough that you can stay away from the danger zone at which point you are in little or no danger, Mauna Loa in Hawaii is a good example of this as nobody lives close enough to the vent to be in danger.
The shield volcano’s shape is actually caused by the way that it forms. Basalt lava, which is thin and flows quickly, oozes out of a fissure in the ground and gradually runs downhill. Basalt lava runs so quickly that it can cover a great distance before it cools and hardens, so shield volcanoes have less steep rises that are extremely large in diameter. This formation process takes a long time, as the lava piles up slowly, eventually resulting in the gradual slope that gives shield volcanoes their name. It makes sense, given the way in which shield volcanoes form (so that their size is gradually increasing and reaches a vast extent) that some of the world’s largest volcanoes are members of the shield classification.
They are made up of either igneous or sedimentary rocks. The rocks are changed due to the intense heat from magma and the fierce pressure from shifting tectonic plates. Even though the rocks get very hot, they do not melt. If these rocks did melt it would result in the formation of an igneous rock instead of a metamorphic rock. Metamorphic alteration causes the texture and mineral composition to change.
These are boundaries where the plats move towards each other but 1 plate travels underneath (subduction). The less dense oceanic plate is the plate that subsides under the denser continental plate. The oceanic plate with melt as it falls to the asthenosphere creating a mantle plume where we expect to see a strombolian (cone) volcano. These volcanoes are typically tall cone shaped volcanoes. They are as such because they lava is andesitic/rhyolitic which means the lava contains 55%+ silica content.
Mud volcanoes, sometimes called ‘sedimentary’ or ‘gas-oil’ volcanoes, are an interesting natural phenomena that occur around the world generally along points of weakness in the Earth’s crust such as fault lines. They act as pressure valves to release gases, mineral water and sometimes traces of oil along with mud also known as breccia from as deep as 10-12 km below the earth’s surface. The size of mud volcanoes very dramatically from 1 to 2 metres to up to 700 metres high; and from centimetres to kilometers wide. Correlations have been found between earthquakes and mud volcano activity particularly if there is a major earthquake. This would explain why the island (thought to be due to a mud volcano) appeared off the coast of Pakistan this fall at about the same time as the large earthquake.