1. A method of processing seismic data, the method comprising: receiving seismic data collected from an array of seismic receivers; selecting a time window during which the array of seismic receivers detected seismic signals including signals generated by a seismic event of interest, and dividing the time window into a plurality of consecutive time segments, each time segment corresponding to a subset of the seismic data; performing a transformation of each subset the seismic data into a frequency domain data subset having a total frequency band bounded by a lowest frequency and a highest frequency; selecting a narrow frequency band including a plurality of frequencies, the narrow frequency band bounded by the lowest frequency and a threshold frequency that is lower than the highest frequency; for each of the plurality of frequencies in the narrow frequency band, determining a cross-spectral density matrix of data values in each frequency domain subset, decomposing the cross-spectral density matrix to generate a plurality of eigenvalues, and removing at least the most significant eigenvalue from each frequency domain subset; transforming each frequency domain subset into a time domain to generate de-noised seismic data; and identifying at least the seismic event of interest based on the de-noised seismic data, wherein the determining, decomposing and removing at least the most significant eigenvalue are performed without comparing the seismic data to any a priori information regarding properties of the formation.