Networked System and Method for Passive Monitoring, Locating or Characterizing Activities

A system for determining localization information for a first energy source positioned below a ground surface based on sensed seismic signals associated with a first signal of interest (SOI) generated by the first energy source, the first SOI including first waveform components associated with a first design frequency for which phase velocity and wavelength of the first waveform components vary based on properties of media below the ground surface, the system comprising:

• a sensor subsystem including a first group of seismic sensors arranged in a first array emplaced below the ground surface, which sensors are responsive to sense seismic energy from the first source in a frequency range extending from 10 Hz to 2 kHz;
• and
• a processing subsystem coupled to receive seismic data acquired from sensors in the first array, the processing system including a processor and storage media having computer instructions stored thereon to perform spatial coherent processing of said first waveform components associated with the first design frequency, where:
• seismic signals which include said first waveform components are received from a first series of sensors in said first group,
• at least one subset of sensors in the first series of sensors has spacings between pairs of the sensors in said one subset rendering the coherent processing of said seismic signals responsive to the first waveform components associated with the first design frequency so that, when coherent processing is performed on seismic signals received from said at least one subset in the first series of sensors, a three dimensional angle of arrival of the first SOI from the first energy source to the first array is determined, and
• relative to one of said first waveform components impinging on a first sensor in said one subset, and having a wavelength associated with the first design frequency, at the first sensor, the first sensor is a point sensor, having maximum dimensions less than five percent of the wavelength.