Japanese Tsunami 2011, Term Paper Example

In 2011, Japan experienced the worst earthquake of magnitude 8.9. The epicenter of the earthquake in the northern coast, about the 80 miles off the coast of Sendai. It is in this subduction zone that the Eurasia plate is over the Pacific plate (Zielinski 1). The tremor occurred in the ocean where the Pacific tectonic plate meets the Japanese plate. There was a violent movement of the sea plate that was uplifted from the continental plate of Sendai Coast. Where the two tectonic plates met, there was a fracturing of the crust for tens of miles. The tremor in the seafloor was intense because the earthquake occurred at a shallow depth of about 15 miles. The energy that was released was intense that it shook the water body mass off to the mainland of Japan. Also, compared with other tectonic plates, the Pacific plate moves faster at the rate of 3.5 inches annually (Thompson 2). It results in building up of enormous energy. The overhead of the Pacific plate sinks as it moves down. Therefore, the joining point breaks leading to the ocean floor to uplift.

In the seafloor, the earthquake ruptured along the fault line. The plates were pushed upward, then dropped. The movement of the plates caused the displacement of water above that mass of the surface. Due upward and downward movement of the chunk of the earth, the energy was put into vertical motion. The water was forced to move horizontally in the form of massive waves towards the mainland. Then the initial tsunami was split. One tsunami moved towards the west coast of the U.S. and Hawaii, while the other tsunami moved towards the Eastern coast of Japan (Tate 3). The tsunami reached to the coast of Japan after one and half hours.

The jolting of the two plates in the ocean caused the waves to rise as which as 7 meters according to the warning center of Hawaii. At the coast of Japan, the waves rose to a height of 4 meters. However, as the tsunami spread in the sea, the height of the waves gradually dropped to about 40 centimeters. South-West of Japan was greatly hit by the tsunami as the waves were seen moving towards that direction. The waves were recorded to be moving at high speed of 500mph. The speed at which the waves move at, depending on the depth of water. The tsunami from a deep sea would move faster than waves from the shallow water towards the shore (Tate 2). Geologists observed that the speed of tsunami waves from deep waters is same to the speed of a commercial jet on the ground.

Another factor that determines the strength of a tsunami is where it originates. The waves from the sea are just a few meters high and spread over a wide area. But, as they approach the continental plate, the shoreline slopes and the water become shallower. Therefore, the tsunami waves start to narrow and increases in height. The waves have two parts, namely, the trough and the peak. The trough is the low point of the wave while the peak is the top part of the trough. With the tsunami waves, the trough part is the first to reach the shore causing the receding of the sea from the coastline. This is a sign that a tsunami is impending. The peak hits the shoreline in a process known as runup. Rarely do tsunamis result from a giant breaking wave apart from during the 2004 event in the Indian Ocean. The tsunami breaks from the vertical movement of water travel further inland, unlike normal waves.

The physical characteristic of coastline plays a significant role in determining the form of a tsunami wave. Straight and relative smooth shores experience small waves. Coasts with irregular coastline and with many inlets bring about higher tsunami waves (Johnson 4). Also, the presence of prominent features on the ocean floor can affect the speed of the wave; hence, the impact upon reaching the shore.

The Japanese tsunami caused the death of many people and destruction of property. For instance, the Fukushima nuclear power plant was destroyed, leading to the declaration of a state of emergency. Homes were destroyed, cars and boats were swept, homes were destroyed, and 15,000 people were killed, and many others went missing (Zielinski 1).  Since then, Japan has taken precautionary measures of protecting its coast from such experiences. It has also embarked on the construction of big buildings that cannot be easily brought down by the earthquake. The buildings are designed in a way that they can absorb the shakings of tremor.

The destruction of tsunami waves is brought about by the strong current and debris floating. Upon breaking on the shore, the tsunami waves do not break once. The run-up Takes the tsunami energy into the open ocean. Edge waves are formed from the trapped waves along the coast and the travel parallel to the shoreline as they move back-and-forth. This can result in the tsunami waves to arrive in multiple instead of in a large wave (Lee 3). The aftershock in Japan is still experienced as the crustal plate is still fracturing along Japan’s trench. However, it is estimated that the future tremors will not be as such strong, and the tsunami is likely to be weak. It is also expected that the energy that will be produced between the North Atlantic and Pacific tectonic plates will cause a sphere earthquake along the fault line.

Works Cited

Johnson, Ethan. “Japan’s megaquake and killer tsunami: How did this happen?” The Earth (2011): 1-5. Document.

Lee, Jane J. “The 2011 Japan Tsunami Was Caused By Largest Fault Slip Ever Recorded.” National Geographic (2013): 1-3. Document.

Tate, Karl. “How Japan’s 2011 Earthquake Happened (Infographic).” Live Science (2013): 1-3. Document.

Thompson, Andrea. “Japan’s Tsunami: How It Happened.” Live Science (2011): 1-3. Document.

Zielinski, Sarah. “Fault That Caused Japan’s 2011 Earthquake Is Thin and Slippery.” Smithsonian (2013): 1-4. Document.