Optimizing 3D seismic survey geometries using ray tracing and illumination modeling: A case study from Penobscot field

Wavefront (WF) construction-based ray-trace modeling is an advanced technique used to assess survey design parameters in three-dimensional (3D) seismic surveys. These parameters play a crucial role in determining the quality (signal-to-noise ratio and signal strength), coverage, and continuity of seismic data during the imaging of subsurface structures. Unlike conventional survey design, which assumes horizontal homogeneous velocity layers and straight-ray propagation, the Earth’s surface consists of inhomogeneous and complex layers. Conventional seismic survey design methods are constrained by their reliance on simplified assumptions that inadequately represent geological complexity. Their limited adaptability to structurally complex environments reduces their effectiveness in optimizing data quality and subsurface imaging. The present study provides insights into how heterogeneous layers, characterized by variations in thickness and petrophysical properties, influence seismic data. The WF construction approach assimilates elastic wave propagation through a heterogeneous and geologically complex Earth medium. This method involves constructing an elastic Earth model with inhomogeneous properties and the propagation of elastic wavefields through the model by strategically positioning sources and receivers in accordance with the designed survey geometry. Illumination (Hitmaps) and Ray hit maps of target layers are generated. The findings indicate that WF construction modeling offers a more accurate depiction of real-time illumination of target layers. In conclusion, WF construction modeling is a valuable tool for assessing the merit of designed survey parameters. It aids in finalizing geometry parameters with a logical understanding and knowing their impact on illumination for target layers.