Multichannel Surface Wave Analysis: A Case Study Evaluating Passive Seismic Recordings Using Geophones and DAS

Passive seismic has been a popular method for subsurface characterization applications, particularly in mapping near-surface properties and shallow mineral deposits. This case study evaluated a cost-effective passive seismic method to determine the cover thickness and its variations, which is crucial for identifying bedrock topography. Rayleigh waves from passive seismic sources were used to compute dispersions and to construct a shear-wave velocity model, a more affordable alternative to active sources. Recorded data from geophones and DAS highlighted their potential and challenges. Improved subsurface modelling was achieved using data from a short recording period with collocated 2D arrays of geophones and DAS in Western Australia’s Pilbara region, combining passive seismic interferometry with MASW.