In trying to establish facts regarding earthquakes, it is important for scholars to be able to know what earthquakes are and what cause them. Moreover, it is also important for scholars to be able to tell what exactly takes place during an earthquake, and to tell where exactly the earthquakes take place. Once that is known, it then becomes important for the scholars to come up with proposals or recommendations on how to stop the occurrence of earthquakes in the future. One way of trying to stop the occurrence of earthquake may be as a result of making correct predictions on the occurrence of the same. If for instance, the earthquakes can be predicted in advance, will it be possible to stop it from taking place? Finally, it is also important for the scholars to tell whether humanity can be protected from the catastrophic effects of earthquake.
Earthquakes can be described as the sudden shake of the earth during which there is a large strain of energy that is released from the surface beneath (Bolt, 1999, p.1). The energy that is released normally travels in the form of seismic waves and it travels mostly along the earth’s surface. Once the earthquake comes to a stop, it leaves behind a trail of destruction on the surface of the earth. One of the most notable changes it creates is the destruction along the tectonic plates. However, such destruction normally re-builds up once the earthquake comes to a stop. The process of rebuild up along the plates is what the scientists refer to as elastic rebound theory. It remains to be a fact that earthquakes are not a new phenomenon to humanity and therefore becomes one of the calamities that can be accurately predicted in advance. Apart from that, earthquakes come with other catastrophic disasters flooding as well as landslides. Therefore the occurrence of such calamities can prove to be very costly to humanity if not predicted well in advance. The author also suggests that an earthquake that occurs on the floor of an ocean can result in a large tsunami wave.
The occurrence of most earthquakes normally takes place along the boundaries of the tectonic plates which then result in a separation of the parts of the earth’s surface. Such a movement is what the scientists call the inter-plate earthquake. On some occasions, the earthquakes take place on the plates themselves, being far away from the plates boundaries. Such occurrence result in what is termed as intra-plate earthquake (Bolt, p.2). What happens in the intra-plate shake is that the tectonic plates do break in between. In both cases, the split that is generated from the earth shake occurs both on the horizontal and the vertical axis of the earth. At times it is possible that any of the formations may dominate over the other.
One of the methodology through which earthquake does occur is through the splitting of the earth’s crust especially in regions where the crust is undergoing deformation (Stephen, 2013, p. 3). The deformation process does occur as a result of the tectonic forces undergoing a gravitational force. In most cases, such deformations occur in regions where the rocks of the earth fracture and as a result produce fractures. What happens to the rocks is that they are constantly subjected to forces within the earth that makes them bend and twist and a s a result make them fracture during such process. The forces behind the deformation of the rocks are referred to as stress. The stress forces normally take place over a given area either in a uniform or a non-uniform manner. A uniform stress is one that takes place uniformly across a certain given area. The reverse is true about a non-uniform stress. In most cases, the pressure that is experienced as a result of the overlying rocks is referred to as confining stress. If the stress does not occur uniformly from all sides then it is referred to as differential stress. The stress that occurs in the earth’s underground can be categorized into three major portions. The first one is the tensional forces that do occur as a result of the stretching of the rocks. Secondly there is the compression stress that takes place as a result of the rocks getting squeezed. Finally there is the shear stress that takes place when there is a spillage and translation.
There are several theories on how the rifts on the earth’s surface are formed in different areas. One of the theories ascertains that the movement of the tectonic plates at different speeds is what may cause an occurrence of the rift. For instance if the tectonic plates move in different directions and at different speeds from those of the neighboring plates, the result is that they may collide at some point. Another suggestion is that the movement of the plates from one another is what may cause them to form the rift. Finally, the third theory suggest that the movement of the plates side by side either in the same or opposite directions is what may result in the formation of a rift and thereby create a weakness point (Stephen, p.5).
An evaluation of the sources reveals that each of the authors had their own way of describing what an earthquake is and how it does take place. The first author describes what an earthquake is extensively and further gives more elaboration on how the quake takes place. For instance, he explains of the formation of the tectonic plates beneath the earth’s surface and how that eventually results in the occurrence of an earthquake. The explanations are further accompanied by further explanations made through the use of diagrams.
The second author just gives a shallow briefing about earthquake and how it possibly does take place. Furthermore, he explains the facts that people need to know about earthquakes and how prepared they can get for the same. The author believes that earthquake is one of the calamities that can easily be predicted and should therefore not be allowed to interfere with humanity. He also goes ahead to explain the areas that may be at most risk of suffering from the catastrophic effects of earthquake.
Finally the third author gives an elaborate explanation of earthquake and all the details that appertains to it. He gives a step by step explanation of how the entire process takes place from the beginning to the end. Moreover, he goes further to give explanations on how the stress and strain experienced underneath the earth does contribute to the occurrence of an earthquake. Apart from that, the author also goes out of his way to explain the different types of stress and how each contributes to the formation of points of weakness on the earth’s surface.
In conclusion, all the articles relate to one another because they all give clear explanations on the occurrence and the effects of earthquake. Their ideologies are more or less the same since they only use different theories and words to explain the same ideologies.