Tilt Precursors in Rock Before Failure: A Laboratory Investigation.
NTIS: PB 250 565 :9 pages
Laboratory measurements by the Bureau of Mines indicate that failure in dry rock specimens measuring approximately 13 cm in length is preceded by tilt anomalies lasting a few milliseconds. The tilt behavior is qualitatively similar to that reported to precede earthquakes. Test results suggest that the time duration of this tilt anomaly for laboratory specimens of this length is independent of rock type, in agreement with theoretical predictions and other experimental data on rock failures including earthquakes.
IH; Report of Investigations
NTIS Accession No.
NTIS: PB 250 565