Seismogram facts for kids

A seismogram being recorded by a seismograph at Weston Observatory in Massachusetts, USA.

A seismogram is like a special drawing that shows how the ground shakes during an earthquake. It's a record of the ground's motion over time. Think of it as the earthquake's signature! These records are usually made by machines called seismometers. Seismometers are super sensitive tools. They can record ground movements in three directions: up and down (like jumping), and side to side (like swaying).

Seismogram of Sylmar085 earthquake in fractions of gravity acceleration, UCSD.

How Seismograms Are Made

In the past, seismograms were drawn on paper. This paper was wrapped around a spinning drum. Some machines used pens to draw on regular paper. Others used light beams to create marks on special photosensitive paper. This paper would change when light hit it.

Today, almost all seismograms are recorded digitally. This means the information is saved as computer files. Digital records are much easier to study and analyze using computers.

Why Seismograms Are Important

Seismograms are very important for measuring earthquakes. Scientists use them to figure out how strong an earthquake was. They also help scientists understand where an earthquake started and how far its waves traveled. One famous way to measure earthquakes is using the Richter scale. Seismograms provide the data needed for this scale.

Images for kids

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  A detail of the seismogram

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  A set of seismograms for an earthquake from the USGS (click to see large version)

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  A container that stores a Develocorder film reel

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  A Develocorder film reel

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  Viewing of a Develocorder film

See also

In Spanish: Sismograma para niños