The Earths Ordinary Way of Releasing Stress - Essay Example

The plates are made up of a rigid, solid rock. The plates interact at their boundaries (margins) or edges. There are various types of plate margins which include; diverging, converging, and transforming faults (Karey, Klepesis, and Vine, 2009).

Converging plate boundary
Converging occurs when two plates travel toward each other. When the plates converge, different types of margins are formed depending on the boundary; the boundary can either be between two continental plates, oceanic plates, or either one of each. One type of convergent margin occurs when a continent meets another continent along the convergent line where they crumple upwards and downwards as the lithosphere thickens in a collision zone. Another type of convergent margin takes place when one or both plates are oceanic where one plate typically slides underneath the other plate sinking into the asthenosphere where water that is released from the wet rocks of the seafloor advances the formation of the magma (Kearney, Klepesis and Vine, 2009).

Diverging plate boundary
Diverge is also known as rifting or spreading centers. Diverging occurs when two plates move apart from each other and can occur in either continental or oceanic crust. When plates diverge from each other a new ocean may form in the widening rift, an example of this is the Red Sea. When the oceanic crust diverts (splits apart) the result is known as a midocean ridge (Kearney, Klepesis, and Vine, 2009).
Transform faults plate boundary
The transform plate boundaries are the locations where plates slide past each other. A crack zone that normally forms a transform plate boundary is well known as a transform fault. The transform faults are most common in the ocean floors (ocean basins) where many of them run perpendicularly to the midocean ridges (Kearey, Klepesis, and Vine, 2009).
Why earthquakes are common along plate margins
Earthquakes occur mostly at the plate margins because under the plates there is much friction and the plates are constantly bouncing off each other. The plate’s margin material is not as sturdy and is found near the molten part. The earthquakes occur normally near the fault lines (this is where the plates are normally separated). In the fault line, two plates confine together until much pressure is formed and they are forced to grind away from each other. The lateral fault line happens frequently and within different magnitudes, an example of a lateral fault line is the San Andreas Fault in California.
How the earth moves when it quakes and shakes
When the earth quakes and shakes sudden movements on the ground occur. The quakes are mostly provoked by movements along the faults, landslides, bomb blasts, and volcanic eruptions. When a quake occurs, the surface of the earth forms into waves that move across; these waves are considered to be pretty spectacular and extremely destructive. During a quake, the seismic waves move about in all directions just like the sound waves (Kusky, 2005).
Events that cause the earth to quake and shake
An earthquake is a ground shaking that is caused by an abrupt slip on a fault. When the pressure in the earth’s outer layer pushes the sides of the faults together causing stress to build up and the rocks to slip all of a sudden discharging energy in waves that travel through the earth’s crust causing the shaking that is felt during an earthquake.

Earthquake measurements
Earthquakes are recorded by seismometers up to great distances as the seismic waves are known to travel through the earth’s whole interior. The absolute magnitude of a quake is accounted for by the numbers on the moment magnitude scale while the felt magnitude is reported using the Mercalli intensity scale. Tremors produce different types of seismic waves which travel through a rock with different velocities, for example, the longitudinal waves produce Compressional waves (shock or pressure waves), while the transverse waves produce the secondary waves and the surface waves which include the Rayleigh and love waves.
Two types of body waves that an earthquake creates
There are two types of body waves that an earthquake creates and they include the compressional waves (P) and the secondary waves (S).
Compressional waves (p)
The compressional waves deform materials through a change in volume and density and can pass through solids, gases, and liquids. The movement associated with the passage of a compressional wave is back and fourth the type of motion (Kusky, 2005).

Secondary waves (s) or the shear waves
The secondary waves change the shape of a material and not its volume hence it does not change the volume of a material. The secondary waves are only transmitted by solids and they move materials at right angles to the point (direction) of the wave travel. The secondary waves consist of alternating series of sideways motions (Kusky, 2005).
Example of an area prone to earthquakes
The locations of various faults and plate boundaries help in determining why certain areas are more prone to earthquakes. In the United States, nearly every state has experienced an earthquake but states along the Pacific coast are believed to have experienced more earthquakes than other regions in the United States. In earthquake-prone areas like Greece, houses are made of elastic material and they are on stilts so that the entire surface of the buildings cannot touch the ground. Read More