How are earthquakes measured??

Question

i want to know how earthquakes are measured. please be specific and and add any links to usefull websites.

Answer 1

By seismographs

Answer 2

There are two different scale to measure the earthquakes. One is the famous Richter scale. You can measure the energy release at the point of focus from a distant place with the use of seismograph. The arrival time of S wave and P Wave is used to find the distance of epicenter.The maximum amount of shaking recorded in seismograph together with the distance is used to calculate the Richter scale.The Richter scale 3 when measured from a distance of 100 K/M will record a shaking of 0.1 mm.This will get increased by ten fold for each Richter scale and in will get reduced by inverse square of distance.See the chart for energy release in each Richter scale. But another use full but not in common use is the Mercalli scale. This will differ from place to place according the intensity felt by the people living in that area.No need for any measuring device.Its start from 1 people can not feel it and ends with 12 where every thing will fly off.The Richter scale is open ended scale .No upper limit for it. But the maximum recorded after the invention of that scale is 9.5 only.

Approximate TNT (Tri nitro telecom )  Yield for Seismic Energy                    

                       Richter scale

                                   1                     30 lbs  

                                   2. 1 ton

     3. 29 ton

     4. 1000 ton

     5. 32000 ton

     6. 1 million ton

     7. 32 million ton

     8. 1 billion ton

     9. 32 billion ton

    10 1 trillion ton.

Answer 3

On the rictor scale.

Answer 4

by the richter scale....it rates them on how much damage is done to the earth..

Answer 5

The ground movement is measured with seismographs, and the intensity rated on the Richter Scale.

Here are some sites:

www.cdli.ca/CITE/earthquakes_measureme...

www.britannica.com/EBchecked/topic/176...

www.intute.ac.uk/sciences/cgi-bin/sear...