Types Of Earthquakes
An earthquake is perhaps the most deadly and the most dangerous natural phenomenon of earth. It is characterized by the sudden tremors on earth’s surface caused due to the release of energy from its crust.
At times the tremors in an earthquake are of such a great intensity that they can collapse an entire city within the time span of just few seconds. Over the years many researches have been made as to how these earth quakes occur? Why they occur? and When do they occur?
Although geologists and scientists today have extensive information regarding their cause, they still are unable to predict when an earthquake will occur. However, there are certain areas which have been given the name of fault lines by the geologists as they believe that these areas are likely to go through an earthquake.
Even though it is still not possible to predict when an earthquake will occur, it is now easily possible to measure the magnitude of the tremors occurred in an earthquake.
In 1935 a device to measure the intensity and the magnitude of the seismic waves of an earthquake, was invented by an American seismologist Charles Richter.
The device is known as the Richter scale. The Richter scale has a scale from 1-9.
An earthquake that falls below the point of 4.5 in the Richter is called a minor one and does not cause much of harm; however an earth of magnitude above 4.5, according to the Richter scale, is capable of causing damage.
An earthquake above 7 is extremely severe and can cause a mass destruction.
An earthquake, simply defined as the shaking of the earth’s surface. On the basis of what causes this shaking, earthquakes are classified into four types. Following are the four types of earthquakes:
The earth’s crust consists of loose broken fragments of lands known as the tectonic plates. These tectonic plates have the ability to slowly and gradually move. Now, these plates can away from each other, towards each other, can collide or can slide past each other.
Major Earthquake Zones And Fault Lines
- Major Earthquake Zones And Disasters
Earthquakes are one of the most hazardous of natural disasters. An earthquake happens due to the tension put on the ground by the tectonic plates when they get jammed or stuck.
- Earthquake Fault Lines
Fault lines are the lines that blot a frontier flanked by two tectonic tableware of the Earth's coating. In places where earthquakes frequently occur, the measurement lengthwise of these liability lines, are fault lines.
Volcanoes And Eruptions
- Types Of Volcanoes
We all know what a volcano is. We have all seen it countless times on the television in documentaries; a huge eruption of earths surface followed by the release of molten red hot liquid called lava.
- Historic Volcanic Eruptions
Volcano - it conjures up vivid, lucid images of red-hot lava spewing out of a looming mountain, like mountain of fireworks gone astray, bruising and charring everything that dares to come in its way.
When the two tectonic plates slide over each other a huge tremor takes place, and that’s how a tectonic earthquake occurs.
Tectonic earthquakes are the most common type of earthquake. It may be of small or of extremely high magnitude. Most of the mass destruction caused by an earthquake over the history is due to the tectonic earthquakes.
The tremors caused by tectonic earthquakes are mostly severe and if they are of high magnitude, they can completely destroy a whole city within seconds.
Volcanic earthquakes are comparatively less common than the tectonic earthquakes and usually occur either before or after a volcanic eruption.
There are two types of volcanic earthquakes: Volcano tectonic earthquakes and L ong period volcanic earth quakes.
The volcanic tectonic earthquakes occur usually after a volcanic activity has taken place. The magma that erupts during an earthquake leaves a space, to fill the space left by the magma the rocks move towards the space to fill it in, causing severe earthquakes.
Most of the times after the release of lava, the lava falls on its vent blocking it, and not letting the pressure release. The retained pressure does not stay for long; it releases with a huge explosion. The explosion causes a severe earthquake, mostly of extremely high magnitude.
The long period volcanic earthquakes occur post a volcanic eruption. Few days before the great explosion, the change in heat of magma below the earth’s surface creates seismic waves, causing an earthquake.
Collapse earth quakes are comparatively small earthquakes and they take place around underground mines.
These earthquakes are also referred to as the mine bursts. The collapse earthquakes are caused by the pressure induced within the rocks.
It results in the collapse of the roof of the mine which causes further tremors. Collapse earthquakes are common in small towns near these underground mines.
The explosion earthquakes are caused due to the nuclear explosions.
These man induced earthquakes are one of the biggest side effects of the modern nuclear war.
In the 1930s during the American nuclear tests many small villages and towns suffered through such tremors, many of them were completely destroyed due to this heinous act.
Earthquake Preparedness And Survival
- Earthquake Preparedness And Safety Measures
Among natural calamities, earthquake is considered to be the most devastating one.
- Earthquake Survival During And After An Earthquake
To survive an earth quake one must first of all know what an earth quake is. An earthquake is the shaking and trembling of the ground.