Divergent Plate Boundary Feature
The Mid-Atlantic Ridge is a divergent plate boundary feature located between Africa and North America. Its length is 75,000 km, which makes it the largest ridge network on the planet (Vecchione et al., 2011). Like any other divergent plate boundary, Mid-Atlantic Ridge is a high area. This feature occurs as plates move away from each other, the crust stretches, becomes thin, and pulls apart. It is constituted by magma that solidifies after flowing through a fissure that is produced as a result of stretching the lithosphere (Lutgens, Tarbuck, & Tasa, 2011).
As to geologic activities associated with the divergent plate boundary, it is possible to mention the creation of new seafloor. For instance, submarine mountain ranges are created, or the ocean basin can be widening (Searle, 2013). Furthermore, shallow earthquake activity is another feature of the divergent plate boundary. The formation of deposits is also a ‘product’ of divergent plate boundaries’ activity.
It is necessary to note that one of the most important economic activities associated with a divergent plate boundary is the extraction of natural resources. These geologic features form such valuable minerals as iron sulfide and lead sulfide (Searle, 2013). These mineral resources are still widely used in various industries. Importantly, some minerals ‘travel’ towards the surface, and when they interact with ground water, such important resource as copper is created (Searle, 2013). Clearly, this process is very slow as it requires millions of years, but people now use the results of the activity of divergent plate boundaries. Other types of deposits created by divergent plate boundaries are salt and gypsum that are found on the surface of evaporated lakes.
Tohoku Earthquake
The Tohoku earthquake of 2011 is one of the deadliest natural disasters that took place in the world. This was an earthquake with the magnitude of 9.0 Mw and five aftershocks with the magnitude of 7 as well as hundreds of aftershocks of M5 (Alcantara-Ayala, 2014). The earthquake of such magnitude caused another natural disaster, a tsunami, which in its turn, led to a number of nuclear accidents in the Fukushima Nuclear Power Plant.
The earthquake occurred due to the subduction of the Pacific Plate under the Honshu plate (Smits, 2014). The earthquake was a result of another massive earthquake that took place in 869. The Tohoku earthquake caused the tsunami, landslides, floods, fires, and accidents in the nuclear power plant mentioned above. This earthquake feature involved almost 20,000 human losses, almost 367,000 people affected, and the economic damage of $210 billion (Alcantara-Ayala, 2014).
The Japan Meteorological Agency sent warnings concerning the earthquake seconds after it occurred and around a minute before it reached cities (Smits, 2014). The agency also sent warnings concerning the upcoming tsunami around 10 to 30 minutes before it reached the coast. Numerous seismometers were used to measure and predict the earthquake. It is also necessary to note that a historical approach was also applied. In 2007, it was estimated that a major earthquake was going to take place within 30 years.
As has been mentioned above, thousands of lives were lost, and thousands of people were displaced. Apart from the major destruction of houses, the region’s infrastructure was damaged significantly or destroyed completely in some places. Roads, railways, airports and so on were damaged or destroyed. Landslides and damaged dams were another major consequence of the earthquake.
References
Alcantara-Ayala, I. (2014). The spatial-temporal dimensions of landslide disasters. In A. Ismail-Zadeh, J.U. Fucugauchi, A. Kijko, K. Takeuchi, & I. Zaliapin (Eds.), Extreme natural hazards, disaster risks and societal implications (pp. 61-77). Cambridge, UK: Cambridge University Press.
Lutgens, F.K., Tarbuck, E.J., & Tasa, D.G. (2011). Essentials of geology. Harlow, UK: Pearson.
Searle, R. (2013). Mid-ocean ridges. New York, NY: Cambridge University Press.
Smits, G. (2014). When the Earth roars: Lessons from the history of earthquake in Japan. New York, NY: Rowman & Littlefield.
Vecchione, M., Bergstad, O.A., Byrkjedal, I., Falkenhaug, T., Gebruk, A.V., Godo, O.R.,…De Lange Wenneck, T. (2011). Biodiversity patterns and processes on the Mid-Atlantic Ridge. In A. McIntyre (Ed.), Life in the world’s oceans: Diversity, distribution, and abundance (pp. 103-121). Chichester, UK: John Wiley & Sons.