Cross-Hole Measurements of Velocity and Attenuation to Detect a Disturbed Zone in Salt at the Waste Isolation Pilot Plant

摘要

Cross-hole ultrasonic measurements were made at the Waste Isolation Pilot Plant (near Carlsbad, New Mexico) to delineate the disturbed zone around drifts and rooms. Using compressional mode waves it was found that there was a small decrease in velocity and a large increase in attenuation immediately after the test room was mined. Disturbances extended at lease 3 metres from a room with a width of 5.5 metres. The results are interpreted as resulting from the introduction of about 0.5% crack-like, pore space. 7 refs., 4 figs. (ERA citation 13:030098)