Frequently Asked Questions About Compression, Compression Stockings, and Armsleeves. We're always glad to any questions you may have. If you need a quick answer, please use our Live Chat service, available from 9:00 a.m. to 6:00 p.m. Monday to Friday by clicking the Chat Now button to the left.
Seismic waves are waves of energy that travel through the Earth's layers, and are a result of earthquakes, volcanic eruptions, magma movement, large landslides and large man-made explosions that give out low-frequency acoustic energy.
Measuring the Size of an Earthquake. Seismic waves are the vibrations from earthquakes that travel through the Earth; they are recorded on instruments called seismographs. Seismographs record a zig-zag trace that shows the varying amplitude of ground oscillations beneath the instrument.