Earth Quake

What is an Earthquake?

• An earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time.

What are the types of Earthquake?

• Tectonic earthquake - caused by breaking rocks
• Volcanic earthquake - caused by volcanic activity
• Explosion earthquake - caused by a chemical or nuclear explosion.

What are the cause of Earthquake?

• Earthquakes are caused by faulting, a sudden lateral or vertical movement of rock along a rupture (break) surface.  

What are the effects of Earthquake?

• The main effects of earthquakes are-
  1.Deformed ground surface
  2.Damage to man made structures
  3.Damage to towns and cities
  4.Loss of human and animal life
  5.Devastating fires
  6.Landslides
  7.Flash floods
  8.Tsunamis
  9.Seiche
  10.Sandblows
  11.Faults 

 Differentiate foreshock and aftershock.

• a foreshock before the big main earth quake
• an aftershock is another earthquake that happens after the main earthquake sometimes the go on for days even weeks

What is Seismograph?

• instrument used to detect and record earthquakes

Differentiate Intensity and Magnitude.

•   Intensity measures the strength of shaking produced by the earthquake at a certain location.  
• Magnitude and Intensity measure different characteristics of earthquakes. Magnitude measures the energy released at the source of the earthquake.  

 Differentiate Focus and Epicenter.

•   Focus is where slipping or releasing of energy along the fault occurs causing the earthquake.
• Epicenter is where the earthquake is felt the strongest. The epicenter can be located above the focus but that can vary depending on the density of the surrounding and nearby rock strata.

Differentiate Rossi-Forel Scale and Richter Scale.

• The Rossi–Forel scale was one of the first seismic scales to reflect earthquake intensities.  
• The Richter Magnitude scale (often shortened to Richter scale) was developed to assign a single number to quantify the energy released during an earthquake. The scale is a base-10 logarithmic scale

Precautionary
. 
Before an earthquake.

• Have a battery powered radio, flash light, and first aid kids in your house.

• Make sure every one knows where they are kep.

• Learn first aid.

• Teach how to stop electric main and gas supply.

• Plan for your family for reuniting after an earthquake if anybody separated.

• -Urge your school teachers to discuss earthquake safety in the class rooms, and ask them to conduct drills.
• Keep some dry fruits and drinking water. 

During an earthquake 

• Stay calm if you are indoors, stay out if you are out of buildings. Many injuries occur as people enter or leave the buildings.

• If you are indoors , stand against the a wall near the center of the building, or get under a study table keep some cushion on your head, Stay away from windows and outside doors, if you are in a high rise building stand against a support column.

• If you are in outdoor stay in the open place , keep away from over head electric wires. and bridges.
• Don’t use open flames, if you are in a moving vehicle stop away from over bridges and stay inside the vehicle still earthquake stops.  

After an Earthquake

• Check yourself and nearby people for injury, provide first aid.
• Check electric and gas connection.
•  Turn on your radio or T.V for emergency instructions, reduce the use of phone lines it may be required for conveying some important messages.
• Stay out of damaged buildings.
• Wear chapels and gloves to protect against shattered glass and debris.