In this paper we describe a number of fundamental seismic attributes that can be determined from passive seismic borehole recordings. Passive data can be used to determine not only direct images of reservoir fracturing, but also background borehole noise characteristics, velocity model details including lateral variations and anisotropic characteristics, seismic attenuation, hodogram response and frequency response, to name a few. Example and limitations of these parameters are given, some of which may be relevant to other borehole seismic studies.