Sonic while drilling has long been considered a major goal by the indu
stry because of its potential applications: real-time determination of
pore pressure and overburden gradients, improved, lithology change de
termination, seismic calibration, and detection of seismic reflectors
ahead of the bit. Until now, only two methods were available to perfor
m sonic measurements while drilling-the use of continuous coring or a
specific measurement while drilling (MWD) tool. Unfortunately, both me
thods remain very expensive and suffer from technical limitations. A n
ew technology [named pulsed ultrasound on cuttings (PUC)] has been dev
eloped to measure both compressional and shear-wave velocities directl
y on cuttings with dimensions as low as 1 mm. Laboratory and field imp
lementations of the method are presented along with its validation aga
inst reference measurements.