Geological Modelling for Seismic Modelling

Summary This paper presents an optimized workflow for the construction of large-scale geological models, specifically designed as inputs for seismic full-wave modelling. Such models can be used in seismic acquisition feasibility studies to propose or optimise survey design. The workflow is demonstrated on an offshore clastic field and the abstract focuses on the innovations in the geological modelling part. In this workflow, advanced geological modelling methods originating from the reservoir modelling discipline are adapted to the construction of a detailed density and velocity model for seismic modelling. A structural model is constructed, from which a geological grid is derived. The grid is then filled with density and velocity properties using geostatistics. New ways for deriving statistical and geostatistical parameters from sparse hard data in the overburden are introduced. The QC of the geological model represents an important validation before running seismic full-wave modelling. This is done by analysing the model in terms of reflection coefficients and by convolution with a simple wavelet. The results can be compared to legacy seismic data to ensure that geological contrasts introduced in the model are realistic.