Jump to main content.  General Crosshole Procedures
Crosshole testing takes advantage of generating and recording
(seismic) body waves, both the P- and S‑waves, at selected depth
intervals where the source and receiver(s) are maintained at
equal elevations for each measurement.  Figure 1 illustrates a
general field setup for the crosshole seismic test method. 
Using source-receiver systems with preferential orientations in
tandem (i.e., axial orientations, which complement the generated
and received wave type/signal) allows maximum efficiency for
measurement of in situ P- or S-wave velocity depending on the
axial orientation.  Due to the different particle motions along
the seismic ray path, it is crucial to use optimal source-
receiver systems in order to best record crosshole P- or S-waves
(Hoar, 1982).  Because only body waves are generated in the
source borehole during crosshole tests, surface waves (ground
roll) are not generated and do not interfere with the recorded
body-wave seismic signals.  S