Explorational Rock Physics – The Link Between Geological Processes and Geophysical Observables

Abstract

The field of rock physics represents the link between qualitative geological parameters and quantitative geophysical measurements. Increasingly over the last decade, rock physics has become an integral part of quantitative seismic interpretation and stands out as a key technology in petroleum geophysics. Ultimately, the application of rock physics tools can reduce exploration risk and improve reservoir forecasting in the petroleum industry.

This chapter covers basic rock physics principles and practical recipes that can be applied in the field. The importance and benefit of linking rock physics to geological processes, including depositional and compactional trends, is demonstrated. It is further documented that lithology substitution can be of equal importance to fluid substitution during seismic reservoir prediction. It is essential in exploration and appraisal to be able to extrapolate away from existing wells, taking into account how the depositional environment changes, together with burial depth trends. In this way rock physics can better constrain the geophysical inversion and classification problem in underexplored marginal fields, surrounding satellite areas, or in new frontiers.

Finally, practical examples and case studies are presented to demonstrate a best-practice workflow and associated limitations and pitfalls. Rock physics models are combined with well log and pre-stack seismic data, sedimentological information, inputs from basin modelling and statistical techniques, to predict reservoir geology and fluids from seismic amplitudes.