Velocity Anomalies in Dilatant Rock

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Science  04 Aug 1978:
Vol. 201, Issue 4354, pp. 441-442
DOI: 10.1126/science.201.4354.441


Seismic velocities measured in rock deformed in the laboratory show excellent agreement with theoretical predictions of the effects of crack growth during dilatancy. Under appropriate conditions dilatancy was observed to produce a drop in the ratio of the seismic compressional velocity to the seismic shear velocity both by the mechanism of undersaturation and by a liquid-gas phase transition.