Negative Seismic Anisotropy in Offshore Suriname

This technical report presents a case study on the estimation of velocity anisotropy in a pre-stack depth migration (PSDM) project conducted in the shallow waters of offshore Suriname. The study highlights the necessity of utilizing negative anisotropy parameters, specifically negative epsilon, to achieve accurate seismic imaging and well ties. The report details the correlation between negative anisotropy and the presence of unconsolidated sand layers, which were found to be significant in the project area. The methodology involved building a macro-scale anisotropy model based on geological changes across the survey area, which improved the overall depthing of seismic images. The report also discusses the challenges faced in deriving reliable anisotropy fields and the importance of well calibration for ensuring accurate results. The findings contribute to the understanding of seismic anisotropy in geological contexts where negative values are typically considered rare, thus providing valuable insights for future exploration efforts in similar environments.