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Ground roll supression using the Karhunen‐Loeve transform

Ground roll is the main type of coherent noise in land seismic surveys, and is commonly much stronger in amplitude than the reflection signals. Standard methods for suppressing ground roll include 1-D high‐pass filtering and 2-D f-k filtering. High‐pass filtering is based on the low‐frequency nature of ground roll, but has the disadvantage that it also eliminates low‐frequency reflection signals which contribute to the character of reflection events and are very important in inversion for acoustic impedance. When the amplitude of the ground roll is much stronger than the reflection signals, f-k filters cause serious distortion of the signal.