There are different seismic sources for both land and marine acquisition surveys. Measuring the spectral characteristics (phase, frequency, amplitude, etc.) is a critical part of evaluating the usefulness of the source and is quite difficult to measure accurately (especially on land). We always seek to generate an impulse (or a Dirac spike).

All this said, my question is this: how and why do different frequencies retain various phase delays and amplitudes? Is this a phenomenon that does not occur the instantaneous moment the source is used...? I used Seismic Unix to generate the figure below - note that a phase diagram is not included here, but you already know that there some degree of phase delay/difference associated with each frequency (note: the horizontal axis is frequency and vertical is amplitude):

enter image description here

If my question seems vague, think of it this way. Let's say I (and my source) are in an infinite, elastic, and homogeneous medium. I set off my source (note that it is NOT a perfect impulse), and the result may look like what is pictured below. What causes frequencies to retain different amplitudes? What causes the phase delay associated with each frequency? I know I've included a lot here, regardless, any insight/comments are greatly appreciated.



Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Browse other questions tagged or ask your own question.