No abstract

No abstract

Seismic interferometry (SI) is the process of generating new seismic traces from the crosscorrelation of existing traces. One of the starting assumptions for deriving the SI representations is that of a lossless medium. In practice, this condition is not always met. Here, we show what the effect is of intrinsic losses on the SI result with the help of a laboratory experiment in a homogeneous sand chamber. Using numerical modelling results, we further show that, in the case of a dissipative inhomogeneous medium with internal multiple scattering, ghost reflections will appear in the cross-correlation results.

The investigation and detection of faults, fractures, karst zones, cavities, etc., is important to reduce hazardous risks, in particular during excavation with tunnel boring machines. To locate such scatterers, we propose a method based on seismic interferometry that uses the noise signals generated by a TBM. Using finite-difference modelling of TBM noise in a homogeneous half-space, we model noise recordings. We then correlate the noise to obtain non-physical scattered arrivals for various scatterer locations. We use both non-physical scattered P-and S-wave arrival times to successfully estimate the location of scatterers.

No abstract