Conclusions

Location of sources of microseismic energy or scatterers at depth is a difficult process due to the presence of strong sources of noise on the surface. We presented a method of suppressing surface noise sources that seems to have been somewhat successful. An important step in the processing is the estimation of the signal of the surface noise source. We have found it helpful to use beam steering to determine the moveout trajectory of energy from the surface source, and then stack the data along this trajectory to obtain a robust signal estimate. Perhaps better methods of estimating the signal of the source will lead to better noise suppression results.

Obviously, the results obtained from such data depend greatly on the quality of the data collection (including the time and place at which the data are recorded). Borehole data would probably yield better results, because it is less sensitive to surface noise sources.