I'mI have been told that the signal in the graph below was obtained by passing a seismogram through a highpasshigh-pass filter to obtain the high frequency-small amplitude waves common in tremors far from the epicenter of an earthquake.
The high pass-pass filter used to unmask the tremor was selected to avoid avoid the 'attenuation' of the tremor signal. What exactly is meant by 'attenuation' in this context?