Advancing Elastic Full-Waveform Inversion – from Structural Interpretation to Amplitude Analysis

Elastic full-waveform inversion (FWI) and its derived reflectivity (FDR) offer new insights into seismic imaging and model building, particularly in complex subsalt environments like the Gulf of Mexico. By integrating long-offset ocean-bottom node (OBN) data, elastic FWI significantly improves velocity model accuracy, leading to enhanced subsalt structural interpretation. In addition to structural imaging, the reliability of FDR amplitudes is evaluated by comparing them with well-log impedance measurements, demonstrating a strong correlation and quantitative consistency. Comparative analysis of FDR and reverse time migration (RTM) gathers highlights FDR’s ability to mitigate illumination gaps, improve signal-to-noise ratio, and extend amplitude ranges for near and far offsets. These improvements suggest that FDR can be a useful tool for amplitude variation with offset (AVO) analysis, supporting its role in quantitative seismic interpretation. These observations indicate that FDR has the potential to contribute to both structural and amplitude-based interpretation in complex geological settings, such as subsalt areas.