Introduction
Just past midnight on December 26, 2004, seismic sensors detected an earthquake measuring 8.9 on the Richter scale (Doc. 8). The epicenter of this earthquake was just off the coast of Indonesia (Doc. 3). As is always a possibility with a large quake (Doc. 4), a massive tsunami, which extended about 1000 miles from its center, was formed (Doc. 1). This tsunami resulted in what according to the UN Emergency Relief Coordinator at the time, “may be the worst natural disaster in recent history” (Doc. 1).
Causes
The Earth’s crust is composed of many islands floating in a sea of magma, which encircles the earth and is constantly circulating. This circulation allows plate movement, which can often result in various natural phenomenon. Among the most common of these are earthquakes. Earthquakes typically occur near transform boundaries, or places where plates scrape past each other. However, they can occur anywhere that plates move.
Near the epicenter of the quake, two plates collided (Doc. 2) to form an incredibly unstable fault line, the Burma-India plate boundary (Doc. 5). As the Indian plate subducted, or slid under, the Burma plate (Doc. 2), rocks caught on the Burma plate and created massive amounts of pressure. As the boundary was 600 miles long (Doc. 1), large amounts of force built up on the plates, setting the stage for a massive earthquake.
On December 26, 2004, the pressure became too much for the plates to bear (Doc. 8); the plates violently snapped. This sent massive vibrations, which are collectively called an earthquake, through the Earth’s crust. These seismic waves travelled all the way from the sea to land, wreaking havoc in their paths. Though earthquakes are always dangerous, they can have a far more ...
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...detect events that may cause a tsunami, supplement these systems (Doc. 10).
A few years after the tsunami, another earthquake and tsunami struck… in Japan. Japan, a country which is constantly pestered by earthquakes and tsunamis, was ready. Alert systems in the Pacific notified people far before the tsunami hit. In addition, emergency planning allowed people to evacuate in an orderly fashion. Due to these efforts, the death toll in Japan was only
Despite all these preparations, the countries around the Bay of Bengal still have much to do. First, various tsunami impeding systems must be constructed. Second, the people of Southeast Asia must be made aware of the various risks that come from living near a seismic boundary. Regardless, this tsunami taught people not to become too comfortable with nature and stay vigilant, for nature strikes when you least expect it.
Earthquakes are best described as a shaking or vibration of the ground caused by breaking of rock. Sometimes they are very strong and other times you would hardly notice them. This shaking occurs when stress that builds up in the crust is suddenly released as the crust breaks free and/or slides against the other pieces of crust. Earthquakes may also be thought of as the breaking of a popsicle stick by applying pressure to both ends at the same time. Should you try this experiment , you will feel the pressure build up as you apply more force until the stick snaps. When the stick snaps you will feel an instant of pain at your fingers as the stress reduces and energy waves move throughout the stick. When the earth's crust is placed under similar types of stress, binding as the stress builds, it will also snap and release the energy into the surrounding rocks, 'ooch'. Thinking about earthquakes will become more clear if you try another experiment.
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
The scenario mentioned above was based on the rupture located along the Cascadia fault line. This fault system runs from Northern California to Vancouver Island about 700 miles off the shore (FOX5). Scientists use to believe that the San Andreas Fault was where a large earthquake tsunami would originate, but recently their attention has shifted to the Cascadia subduction zone which is now said to be much more dangerous than previously thought (FOX5). Recent earthquake events have added even more tension and possibility for a large-scale tsunami. On March 10, 2014, a 6.8 magnitude earthquake struck off the coast of Northern California, which put a lot of stress on the Mendocino Triple Junction (Davidson). The Mendocino Triple Junction is where three tectonic plates collide, and is very unstable (Davidson). This junction has all this built up pressure and is about ready to explode. Scientists believe that this junction will be the origin of a tear along the 680-mile long Cascadia Subduction Zone. (Davidson). The disaster that follows will be considered the United State’s largest modern-day earthquake.
The tsunami in Thailand that occurred on December 26, 2004, was by far the largest tsunami catastrophe in human history. It was triggered by a magnitude 9.1-9.3 earthquake along the Indian-Australian subduction zone off the northern coast of Sumatra. The tsunami waves traveled primarily in the east to west direction and caused major damage along the coasts of southern Thailand. Unpredictably, it was a violent earthquake beneath the sea that initiated the massive waves and struck more than a dozen countries in Southern Asia. It also destroyed thousands of miles of coastline and even submerged entire islands permanently. Throughout the region, the tsunami killed more than 150,000 people, and a million more were hurt, homeless, and without food or drinkable water, making it perhaps the most destructive tsunami in the modern history. In spite of peninsular Thailand's location facing the northern part of this subduction zone, the lack of any written historical records, together with the lack of any major local seismic activity, the tsunami caused thousands of fatalities and huge economic losses in the popular tourist regions in Thailand. Immediately after the disaster, numerous organizations and individual citizens have helped out and contributed to this devastating tsunami. Indeed, the tsunami in Thailand was a worldwide event, with significant wave action felt around the world. In this context, I am focusing more on the key features of the tsunami’s natural causes, the psychological effects on citizens, the perspective of socio-economic impacts and the consequences of the tsunami calamity.
The 2004 Indian Ocean earthquake and tsunami took place on December 26th, 2004 and had a magnitude of 9.15. The cause of the Sumatra Tsunami was due to the sliding of two tectonic plates. Sumatra, an island in Indonesia, is situated on the boundary of the two plates; part of Sumatra is situated on the India/Australian plate and the other part is on the Eurasian plate. The Indian/Australian plate and Eurasian plate connect on the ocean floor at the boundary, a little over 100 miles off the short of Sumatra. Sumatra was one among the many countries that was impacted by these natural disasters. To fully understand the Sumatra Tsunami one must examine the events that led up to it, what a tsunami is, and the damage caused.
Before examining the Northridge event, understanding the naturally occurring hazard that is an earthquake will help to better understand exactly what happened and why it was such an important geological event. With four distinct layers, two layers, the crust and upper portion of the mantle, compose the skin that is the surface layer of the Earth. The crust is not a single, continuous piece. It is actually several different pieces, or plates, that come together to form the puzzle that comprises the surface of the Earth. These plates are in constant motion rubbing against one another. These areas, known as fault lines, where the plates rub up against one another have spots where one plate ”gets stuck while the rest of the plate keeps moving. When the plate has moved far enough, the edges unstick and is how most of the earthquakes around the world occur” (Wald, 2012). The energy stored from the friction of the two plate...
Additionally, this earthquake occurred on a thrust fault. This fault was a subduction zone slip which occurred primarily beneath the ocean were the Pacific plate plunges underneath the North American plate. This sudden upward movement of the sea floor along the rupturing fault generated a massive tsunami. This vertical deformation
The earth is split into four layers, inner and outer core, the mantle and crust. The top of the mantle and crust make up what is like the skin of our earth (see source 2). The skin is split up like a puzzle and we call these puzzle pieces’ tectonic plates (see source 1). These plates are constantly moving and the plate boundaries (edges of the plates) move and slide past one another. Sometimes as the plates move the plate boundaries become stuck. Pressure builds up in the stuck area over time and eventually breaks. This is why earthquakes occur due to the sudden movement of the plate sliding and breaking creating a fault line to go off. The fault line is the line on which the
The Pacific plate is moving northwest in relation to the North American plate, and it is believed that the total displacement along the fault since its formation more than 30 million years ago has been about 350 mi. Movement along the fault causes earthquakes; several thousand occur annually
While the early warning saved thousands of people, the Japan’s Meteorological Agency underestimated this earthquake as the subduction zone of Japan should not produce the magnitude 9.0 quake (Oskin, 2013a). The Tohoku Earthquake and its tsunami approximately killed 16 thousand people, injured 6 thousand people and around 3 thousand people were missing. Most people died from drowning. Around 300 thousand buildings, 4000 roads, 78 bridges, and many more were affected by the earthquake, tsunami, and fires from leaking oils and gas. Electricity, telecommunication, and railways were severely damaged. The debris of 25 million tons was generated and carried out to the sea by water (BBC News, 2012). The country’s authorities estimated more than 309 billion US dollars of damages. Landslides occurred in Miyagi and liquefaction in Chiba, Tokyo, Odaiba, and Urayasu (USGS, 2013). Furthermore, the tsunami destroyed protective tsunami seawalls. Approximately 217 square miles of Japan covered in water (Oskin,
Earthquakes are caused by tectonic plates moving in the earth's crust. They either move apart or pull together at faults. Two forms of faults are normal faulting where the hanging wall moves downward causing rocks to be pulled apart by tension and reverse faulting, which is the opposite where the hanging wall moves upward casuing rocks to be forced together by tension. These movements cause tectonic plate boundaries called divergent boundaries, convergent boundaries and transform boundaries. Each boundary is different and play a
They are the earth’s crust; they move very slowly every year. As the tectonic plates slide over each other they cause earthquakes. Earthquakes produce various damaging effects this includes damage to structures of buildings, bridges and other standing formations which then...
The death toll climbs to over 10,000 and is still rising (Branigan 2). The disaster in Japan began without warning on Friday March 11, 2011 at 2:46pm with a 9.0 magnitude earthquake, the strongest ever recorded in the country (Fackler 3). A massive thirty-three foot high tsunami, generated by the earthquake, swept over lands in northern Japan, taking objects and debris with it. To make matters worse, the tsunami caused the cooling systems at several nuclear power plants to fail. The disaster in Japan was a tragic event, and it had a plethora of causes and effects.
The interior structure of the earth is made up of crust, the mantle and core (inner core and outer core). Earthquakes occur on the crust. Crust forms the external layer of the earth surface. On the crust, the plate tectonics forces are in charge of causing the abrupt earth movements. Due to the existence of an immense temperature and concurrent pressure difference in the outer layer and inner layer of the earth, convection currents occur at the mantle. This energy results from overwhelming decomposition of radioactive substances contained by the rocks found at the interior of the earth. The developed convection currents lead to movement of lava; cold lava finds its way to the interior of the earth crust, while the molten lava which is generally hot, leaves the interior of the earth to the outside of the earth crust. These kinds of circulations occur at different locations of the earth surface and consequently results in segmentation of the earth due to movement in different directions.