Earthquake| Causes & Effects| Short Essay for Students and Children of Class | 10th,11th,12th
Outlines:
- Definition of Earthquake.
- Definition of Seismology.
- Definition of Seismologists.
- What are the Faults?
- What are waves?
- Definition and types of seismic waves.
- Effects.
- Prediction.
An earthquake is a hasty violent action of the Earth's surface. It appears when an ample of
energy, saved within the Earth, is set free. This power is passed down to the
floor of the earth via earthquake waves. The shaking of the Earth's crust determines
the intensity of earthquakes. Earthquakes vary from small imperceptible
shaking to large shocks felt over thousands of miles. They are able to deform
the ground, make homes and different systems fall apart, and create tsunamis. The
study of earthquakes is called seismology. The analyst who studies earthquakes
is called seismologists. Seismographs are machines that record earthquakes.
The
factor in the earth wherein an earthquake originates is referred to as the
point of interest. The point on the earth’s floor at once above the focus is known
as the epicenter. If the focal point is near the surface i.e., between 0.0 and
70.00 km deep, a shallow-focus earthquake is produced. If it is between 70.00
and 700.00 km deep, a deep-focus earthquake is produced. As shallow-focus
earthquakes occur near the surface, they tend to be larger and more damaging.
Causes and Effects:
1. Faults
The
principle is that the earth's crust is a product of tectonic plates. These plates
are lying side by side. The area where these plates conjoined are called
faults. Faults are essentially cracked among those plates on the earth's floor or
in the earth. The surface between the two sides of a fault lies in a plain.
Sometimes, the fault plane dips into the ground. The rock hanging over the
dipping fault plane slips down into the ground. It is called a normal
fault. When the swaying wall slips upward, it is called a reverse fault. Both
these facts produce vertical displacements. Sometimes the tectonic plates slide horizontally
in the fault plain. Such a slip in the fault plain produces horizontal
displacements. The faults where such a movement takes place are called
strike-slip faults.
2. Waves
The
sudden movement of rocks along a fault cause vibration. Those vibrations
transmit power thru the earth in the shape of waves. These waves are called
seismic waves. They are classified into four types. They are P (primary)
waves. S (secondary) waves, Love waves, and Rayleigh waves. P and S waves
are formed within the earth. The alternative two waves are produced along the
surface of the earth. The P wave travels at the highest speed. It can be accrued
by both solid and liquid materials. With a P wave, the transmitting rocks are equivalently
packed and dispersed.
The
S wave travels only through solid material within the Earth. The S waves are shearing waves. They motion the ground back and forth.
Love
and Rayleigh waves travel from the epicenter along the surface of the Earth.
These waves also cause damage to structures, as they shake the ground
underneath the foundations of buildings and other structures.
3. Effects
Earthquakes
result in landslides and other soil movements. These exercises cause a considerable loss
of property and life. Earthquake waves shake buildings and cause weak
structures totally collapse. If an earthquake occurs in an ocean, it may cause
tsunami waves. Secondary damage from the earthquakes includes economic loss,
diseases, lack of food, and a dearth of clean water. Catastrophic earthquakes can
spread contagious diseases. Disturbance to water supply lines and sewage lines causes conditions that apply toxic diseases.
4. Prediction
Seismologists
try to predict earthquakes. This prediction may include a specific time, place,
and size of the expected earthquake. In this regard, scientists take help
from the previous record of earthquakes. This helps them to determine the
expected repetition of earthquakes. Seismologists also measure the movements
along major faults.
In
spite of all this, the prediction of earthquakes should always be taken as
uncertain. The prediction just talks about the likelihood of an earthquake in a
particular area and in a specific time interval. But its occurrence should
always be regarded as a chance event.