Paper contribution

Combined geophysical techniques to predict and map rock mechanics parameters

Anton Kepic; Duy Thong Kieu; Amirreza Shakib; Maryam Parsajoo

Proceedings
EUROCK 2026
Pages
485-490
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Rock strength and hardness is often interpolated from relatively sparse data spanning tens to hundreds of metres away from diamond-core drilling or interpolated by hand logging and interpretation of rock-core. Geophysical methods should be the natural supporting data for inferring and interpolating information around and between boreholes. Fundamental shared relationships between geophysics measurements and mechanical properties of rock have been noted, tested and studied. However, a well-structured, statistically testable, and economically viable approach of melding geophysical measurement and rock engineering properties does not seem to be regular practice in the mining, or in many civil engineering projects. Cross-borehole seismic tomography while drilling with instrumented/logged holes gathering data appears to be most ready to meet the current and future digital mine-civil engineering needs for useful high resolution, volumetric information. By imaging subsurface rock properties through the analysis of seismic wave propagation, tomography provides valuable insight into the structural, mechanical, and dynamic behaviour of rock masses. Providing 3D maps of P- and S-wave velocity in a block model offers vast potential in decision making by allowing informed plans instead of reactive measures or allowing dilution or waste. At the former Brukunga pyrite-sulphur mine site (in South Australia) we have been investigating the possibility of using cross-borehole seismic travel time tomography with enhanced analysis of borehole wireline data to predict fracture intensity (such as RQD) and rock strength (UCS) as a case history test whether we can predict rock mechanical information and extrapolate to a rock volume. Our proposed methodology provides quantitative and repeatable measurements suitable for physical modelling and offers the opportunity to populate rock block models with engineering data in engineering units.

Contributors

Authors

  1. Anton Kepic RoqSense, Australia ORCID 0000-0003-2850-7818
  2. Duy Thong Kieu RoqSense, Australia
  3. Amirreza Shakib Adelaide University ORCID 0009-0004-8005-2296
  4. Maryam Parsajoo RoqSense, Australia

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References

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