Your essay should do the following things:
Discuss how the different types of waves are formed and describe how the waves travel.
Explain how scientists use waves to track and analyze earthquakes.
Cover recent events involving earthquakes and/or tsunamis that illustrate the points made in your explanation.
Tsunami refers to the phenomena when any particular large water body experiences displacement leading to the formation of long wavelength of water which reaches the shore. One of the most common reasons for tsunamis is underwater earthquake. The earthquakes typically are caused when there is a pushing of tectonic plates against each other. Thus, it forces the tectonic plates to slide under one another leading to shifting of the earth crust. This leads to a fast change in the sea floor level (ITIC, nd). During this process, the water directly above the shift of tectonic plates tends to either rise or fall which leads to the creation of a wall that is rises above the surrounding area. The surrounding water tends to make a shift leading to the water displacement. Considering that the rise or fall in sea floor is typically in miles, hence the water displacement is capable to covering vast stretch of oceans (Colla, 2017). This process is pictorially denoted below (ITIC, nd).
The tsunamis are not directly caused by the seismic waves (i.e. P wave and S wave) and these waves are more relevant for land based phenomena. Even if there is an undersea earthquake which does produce seismic waves but earthquake would not result unless there is resultant displacement of water (Colla, 2017). The 2004 Tsunami was caused due tectonic earthquake near the west cost of Sumatra. It was caused due to subduction of the Indian plate by the Burma plate which produced a significant amount of water displacement leading to Tsunami formation as explained above.
Colla, B. (2017) How does an Earthquake form Tsunami? online] Available at https://sciencing.com/earthquake-form-tsunami-8714524.html [Accessed April 7, 2018]
ITIC (n.d.) How do earthquakes generate Tsunamis? [online] Available at https://itic.ioc-unesco.org/index.php?option=com_content&view=article&id=1158&Itemid=2026 [Accessed April 7, 2018]