Nodal Landstreamer vs. Planted Geophones for Seismic Imaging of Shallow Crystalline Bedrock: a Comparative Performance Study

Abstract

Summary In this study we evaluate a combined approach for seismic imaging of a shallow crystalline bedrock using a fixed deployment of nodal seismic receivers and a moving array involving newly developed, state-of-the-art landstreamer. The main advantage of using longer-offsets planted geophones is manifested via capturing reflections arriving at later times and/or increasing the reliability of the velocity analysis. Moreover, the planted geophones are less exposed to short-offset source-induced noise. The benefits of landstreamer are the flexibility of deployment, default dense receiver spacing allowing recovery of details in the near-surface and broader frequency spectrum. The datasets were analysed using reflection processing and MASW. Our results indicate that both the landstreamer and the nodal spreads can provide consistent bedrock and near-surface imaging, whereas the deeper reflections are recovered only on nodal array. Our approach demonstrate that the methodology and the systems employed are suitable not just for geoenergy site investigations, but for a wide range of seismic imaging applications in crystalline terrains and beyond.