Seismic-guided estimation of log properties (Part 1: A data-driven interpretation methodology)

Seismic data are routinely and effectively used to estimate the structure of reservoir bodies but often play no role in the essential task of estimating the spatial distribution of reservoir or rock properties. Yet, for a long time, we have been using attributes or other features of seismic data to gain useful clues in the interpretation process. Since the 1960s, we have known that reflection amplitude is sensitive to the thickness of thin beds. In the 1970s, bright spots were discovered to be useful in forecasting the presence of gas sands. Then, in the 1980s, amplitude variation with offset (AVO) analysis was identified as an even more refined indicator for gas sands or other situations, giving rise to Poisson’s ratio contrasts. Other examples exist, such as predicting porosity from calibrated acoustic impedance values computed from seismic data.