What are the three types of seismographs?
To overcome this problem, modern seismograph stations have three separate instruments to record horizontal waves – (1) one to record the north-south waves, (2) another to record east-west waves, and (3) a vertical one in which a weight resting on a spring tends to stand still and record vertical ground motions.
What seismogram means?
A seismogram is a record written by a seismograph in response to ground motions produced by an earthquake, explosion, or other ground-motion sources.
What is the difference between seismograph and seismogram?
The terms seismograph and seismometer are often used interchangeably; however, whereas both devices may detect and measure seismic waves, only a seismograph possesses the capacity to record the phenomena. A record produced by a seismograph on a display screen or paper printout is called a seismogram.
What is the importance of seismogram?
A modern seismograph can help scientists detect earthquakes and measure several aspects of the event: The time at which the earthquake occurred. The epicenter, which is the location on the surface of the earth below which the earthquake occurred..
What does a seismogram look like?
When you look at a seismogram, there will be wiggly lines all across it. These are all the seismic waves that the seismograph has recorded. Most of these waves were so small that nobody felt them.
How do you read a seismogram?
The seismogram is “read” like a book, from left to right and top to bottom (this is the direction that time increases). As with a book, the right end of any horizontal line “connects” with the left end of the line below it. Each line represents 15 minutes of data; four lines per hour.
Why are seismographs so important?
A seismometer, or seismograph, is a device that geologists use to measure and record seismic waves. By studying these recordings, scientists can map the earth’s interior, and they can measure or locate earthquakes and other ground motions.
How are seismograms created?
When there is an earthquake, everything in the seismograph moves with the Earth except the weight with the pen on it. As the drum and paper shake next to the pen, the pen makes squiggly lines on the paper, creating a record of the earthquake. This record made by the seismograph is called a seismogram.