ISRM Suggested Methods for borehole geophysics in rock engineering

In recent years, many geophysical methods have been used in rock engineering. For effective application of geophysics, it is important to ensure that all aspects of a geophysical survey from the planning to the reporting are properly implemented. To assist this in the field of rock engineering, the suggested methods for geophysics have been drafted by the International Society for Rock Mechanics Commission on Application of Geophysics to Rock Engineering. Those for the land geophysics were already published in this journal last year. This is the second volume of the suggested methods which describe borehole geophysics. Considering the present status of their utilization in rock engineering, six types of geophysical methods used in boreholes, velocity measurement along a borehole, electric and electromagnetic logging, nuclear logging, vertical seismic profiling, seismic tomography and resistivity tomography are described. In addition, since tunnels can be considered as boreholes, Seismic Ahead of a Tunnel Face is also included in this volume because it has been often used in tunneling. For each of the methods, the following seven aspects of their deployment are described: general, applicability, planning, field operation, data processing, interpretation and output and report. Great emphasis is placed on aspects of planning and interpretation because they become more important in recent application of geophysics to rock engineering.