EXPERIMENT ON INFLUENCE OF STRESS STATES ON ELASTIC WAVE VELOCITY

The influenes of triaxial stress states on the elastic wave velocities of clayey sandstone, and claystone and hard siliceous sandstone have been determined by experiments. Claystone and clayey sandstone show hardly any changes in the v^P/v^s ratio. For siliceous sandstone there is aminimum in the ratio of the wave velocities at 90% of the failure stress. This minimum especially present in the siliceous sandstone previously treated with heat.