Author: Pacific Disaster Center
The Pacific Disaster Center's mission is to provide applied information research and support for the development of more effective policies and, programs, for the disaster management. PDC give information and help during times of natural disaster. PDC Helps people during Natural calamities
An Earthquake is a sudden movement of the ground that releases the elastic energy stored within the rocks, creating destructive seismic waves. The word "seismic" comes from the Greek word "seismos" meaning an earthquake. These quakes are not isolated events. They come with smaller shocks, called aftershocks, with smaller effects.
An earthquake is caused when two sides of a large fracture in the rocks within the earth slide past each other. This fracture is called a fault, which may be microscopic or thousands of kilometers in length, while their width is usually a few millimeters or a few meters in size.The size of an earthquake depends on the area of the fault that ruptured, and the distance through which the rocks on the two sides of the fault slide past one another.Small earth quakes are caused by small faults or small parts of big faults. These last only for a fraction of a second and usually unnoticed, as the rocks on either side of the faults are not displaced much. The larger ones are caused due to faults which are tens to thousands of kilometers long, taking minutes and the displacement of the rocks is around tens of meters.
Earthquakes are caused because the earth is regularly cooling since it was born, the seismic wave being one of its ways to release the elastic energy.
Earthquakes are generally categorized into three types: Tectonic, Volcanic and Artificial.
Tectonic earth quakes are the most devastating, and unfortunately the most unpredictable. The volcanic quakes are seldom important or devastative, but they help predict the eruption of volcanoes. The artificial ones are caused due to human activities, like pumping fuels deep into the earth or due to explosives, and several other reasons.
MEASUREMENT OF EARTHQUAKES:
The most popular scale used to measure earthquakes is the Richter scale, named after Charles Francis Richter (US).This scale measures the energy released at the focus of the quake, read through a seismograph which gives the direction and force of the quakes. An earthquake of size 8 is 10 times more devastative than size 7, 100 times more destructive than 6, and so on. the frequency of earthquakes decreases as the magnitude increases, as the earth experiences about 800 earth quakes of size 5-6 , but only one or two quakes of size 8-9.
EARTHQUAKE EFFECTS:
Earthquakes cause great loss of life by causing damage to buildings, bridges, dams, etc. they can trigger devastating landslides. Fires can begin due to leaks in Gas plants and electrical lines. Earth quakes can also generate tidal waves, or the tsunamis, capable of destroying entire townships. These quakes also cause liquefaction of soils, which makes soil lose almost all its strength, which makes it function like quicksand. This material is capable of swallowing an entire building within itself.
Earthquakes around the world cost around 15,000 lives per year. Several countries like the United States of America, China, Japan and Russia are most actively participating in seismological research, trying to predict future earthquakes.
- Related Videos
- Related Articles
- Ask / Related Q&A




Summit Cube-Sized Freezers
By: Jeremy Linder | 01/01/2010Summit cube-sized freezers are suitable for biological specimen storage, and preservation of tissue, plasma, blood cells and other materials.
Finest Cell Phone skins for your cell Phone
By: BhratBrij | 01/01/2010Looking for cell phone skins which you can customize and personalize according to your own specifications? There are places where you can do exactly that in your choice of HTC G1 skins and Verizon HTC Touch pro skins.
Samsung Rant skins can customize your cell phone
By: BhratBrij | 01/01/2010Go on to the Internet and look around for the best places where you can get customized cell phone skins. Samsung Rant skins, and Samsung Rogue skins are quite easily available on the Internet.
Search for the Finest Cell phone skins of your choice
By: BhratBrij | 01/01/2010Cell phone skins are the best protective cell phone skin accessories. That is why IPhone skins and Itouch skins are joining the fashion scene with other cast vinyl cell phone skins as the most attractive cell phone protectors in the world today.
StudentScholarships.org - The Microwave Oven is the Invention of the Century
By: Drew Backley | 31/12/2009Microwave oven: a convenient electronically operated oven that uses microwaves to generate heat with in the food, it’s fast, and it saves lives. OK, maybe it doesn’t save lives (but I’m sure it’s saved some marriages) but, in my opinion it is the most innovative invention in the past 50 years.
Converting Water into Fuel
By: jerzy jagielski | 31/12/2009Converting Water into Fuel has been a practice utilized for hundreds of years. The First water powered engine was supposedly invented in the early seventeenth century.
How to generate infinite renewable energy!
By: Said Benrida | 31/12/2009To generate an infinite renewable energy all we need is the unlimited disk space. That’s true. With that space we can make an infinitely powerful processor, a processor with unlimited disk space and unlimited memory. This processor can process unlimited number of jobs at an infinite speed, I mean instantly.
Hands free for regular use
By: Kimgonzalez | 31/12/2009There is 40% chances increses for accident if you are driving and talking on mobile without Hands free.Hands free is biggest gainer product for every people who have to fine up for chatting when driving on high way. Wired headsets are the choice of many people who want to be hands-free without worrying about sound quality, price and a battery that might go dead in the middle of a conversation,but it is cheap in compair of bluetooth hands free.
Information About the Floods
By: Pacific Disaster | 17/11/2006 | NatureA flood is an overflow of water, an expanse of water submerging land, a deluge. Floods are most commonly widespread of all natural disasters. They are also one of the most dangerous disasters as they carry enough power to change the shape of land on Earth.
Theoretical Concept of Hail
By: Pacific Disaster | 17/11/2006 | NaturePrecipitation is one form of hail. Hail in other sense means falling of balls or irregular lumps of ice (hailstones), 5 mm-50 mm in diameter on average, with much larger reported from severe thunderstorms. Thunderstorms always produced by cumulonimbus. small hailstones are >5 mm in diameter. They are layered and can be irregular and clumped together
Introduction to Tsunami and Its Preventions
By: Pacific Disaster | 14/11/2006 | Naturewhen a body of water, such as an ocean is rapidly displaced on a massive scale then we call it tsunami. It Is a series of waves. The effects of a tsunami can range from unnoticeable to devastating. There are various reasons behind the tsunami
Causes and Remedies of Earthquakes
By: Pacific Disaster | 06/11/2006 | TechnologyAn Earthquake is a sudden movement of the ground that releases the elastic energy stored within the rocks, creating destructive seismic waves. The word "seismic" comes from the Greek word "seismos" meaning an earthquake, . These quakes are not isolated events
All About Tropical Cyclone
By: Pacific Disaster | 31/10/2006 | EnvironmentA tropical cyclone evolves when the storm system fueled by the heat released when moist air rises and the water vapor in it condenses. The earth's rotation also imparts an acceleration.
How to Prepare your Self for a Hurricane
By: Pacific Disaster | 26/10/2006 | TechnologyA severe tropical cyclone with sustained winds of 74 mph (64 knots) or greater is a Hurricane. Major hazards include high winds, heavy rainfall, flooding, storm surge and high surf. Hurricane is the term used for systems located in the central and eastern Pacific regions.