The main problem of microseismic monitoring is a high coherent noise from surface sources. A significant part of the high-amplitude coherent component is eliminated at the stage of data pre-processing by the optimization method of quasi-harmonic noise filtering. Applying the method of maximum likelihood, the signals from the sensors with a high level of surface noise automatically get a low weight in the assessment of the most likely amplitude of seismic emission sources.

Processing and interpretation of FWL data includes the following:

• static and relief corrections
• identification of microseismic activity zones based on microseismic emission sources location

Results of FWL survey are maps showing the development of microseismic activity zones.