1. A method of acquiring low frequency seismic data about the travel of naturally occurring seismic waves through the earth in a region of interest, comprising the steps of: deploying uniaxial sensors along a receiver line at the surface of the earth in the region of interest; sensing with the deployed uniaxial sensors movements of the earth in response to the travel of naturally occurring seismic waves; forming a record of sensed earth movements as a function of time to form passive seismic data; bandpass filtering the passive seismic data to remove frequency components above a low frequency limit; decomposing the bandpass filtered passive seismic data in the FK (frequency-wavenumber) domain into coherent mono-dominant velocity and dip-angle components; and processing the decomposed bandpass filtered passive seismic data.