Ground roll
| Dictionary entry for Ground roll (edit) |
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<translate> {{#category_index:G|ground roll}} Surface-wave energy that travels along or near the surface of the ground. It is usually characterized by relatively low velocity, low frequency, and high amplitude. Ground roll tends to mask desired reflection signals. Source and geophone patterns, frequency filtering, f-k filtering, and stacking are used to discriminate against it. It is usually a modified Rayleigh wave (q.v.), and ground roll is sometimes called pseudo-Rayleigh waves. See Figure R-3. </translate> |
Ground roll is the main type of coherent noise in land seismic surveys and is characterized by low frequencies and high amplitudes. Ground roll is mainly composed of Rayleigh waves.
Surface-wave energy that travels along or near the surface of the ground. It is usually characterized by relatively low velocity, low frequency, and high amplitude. Ground roll tends to mask desired reflection signals. Source and geophone patterns, frequency filtering, f-k filtering, and stacking are used to discriminate against it. It is usually a modified Rayleigh wave (q.v.), and ground roll is sometimes called pseudo-Rayleigh waves. See Figure R-3.
About Rayleigh waves
Rayleigh waves are a type of surface acoustic wave that travel on solids. They can be produced in materials in many ways, such as by a localized impact or by piezo-electric transduction, and are frequently used in non-destructive testing for detecting defects. They are part of the seismic waves that are produced on the Earth by earthquakes. When guided in layers they are referred to as Lamb waves, Rayleigh–Lamb waves, or generalized Rayleigh waves.