A seismic data collection unit having multiple separate geophones/geophone
packages positioned in a housing wherein the geophones are offset from a
vertical axis so that summing of the geophones' respective outputs
minimizes certain noise in the unit's output. Specifically, the offset
geophones are physically positioned or mathematically configured so as to
be symmetrical about a selected vertical axis in order to cancel out
certain noise in a seismic signal. The particular placement of the
geophones within the housing is preferably selected so that the vertical
axis around which the geophones are positioned passes through the center
of gravity of the unit.