Rock Physics Modeling in Sandstone Reservoirs – Review of Theoretical Models and a Field Example

Document Type : Original Article

Author

Assistant Professor, Institute of Petroleum Engineering, College of Engineering, University of Tehran

Abstract

In this paper, we begin with a discussion on the relations between seismic velocity and porosity in clastic reservoirs. We then provide a brief overview of the theoretical background for some important rock physics models in granular media, including friable-sand model, contact-cement model and constant-cement model. We then present an example of application of rock physics modeling to a well log and core dataset extracted from a real case study. Based on a rock physics diagnostic technique, it is possible to quantify different diagenetic and sedimentologic factors in terms of rock physical properties. In this study, on a real dataset, this is carried out by adjusting the curve of a rock physics theoretical model (constant-cement model) to a trend in the velocity–porosity dataset, and then interpreting the rock physics/microstructure as that used in the theoretical model. This model is then used to make prediction of seismic velocities. The results of this study can be used to interpret the seismic data quantitatively and update the reservoir property models.

Keywords

References

Avseth, P., J. Dvorkin, G. Mavko, and J. Rykkje, (2000(. Rock physics diagnostic of North Sea sands: Link between microstructure and seismic properties: Geophysical Research Letters, 27, 2761–2764.
Avseth, P., Mukerji, T. and Mavko, G., (2010). Quantitative seismic interpretation: Applying rock physics tools to reduce interpretation risk. Cambridge University Press.
Berryman, J. G., (1995). Mixture theories for rock properties. In T. J. Ahrens (Ed.), Rock physics and phase relations: A handbook of physical constants (pp. 205–228). Washington: American Geophysical Union.
Castagna, J. P., Batzle, M. L., & Eastwood, R. L., (.985), Relationships between compressional wave and shear-wave velocities in clastic silicate rocks. Geophysics, 50, 571–581.
Greenberg, M. L., & Castagna, J. P., (1992). Shear-wave velocity estimation in porous rocks: Theoretical formulation, preliminary verification and applications. Geophysical Prospecting, 40, 195–209.
Dvorkin, J. and Nur, A., (1996). Elasticity of high-porosity sandstones: Theory for two North Sea data sets. Geophysics, 61(5), 1363-1370.
Emami Niri, M.E., (2015). Seismic data integration and multi-objective optimization for 3D reservoir characterization and model building. Ph.D dissertation, University of Western Australia.
Gal, D., Dvorkin, J., & Nur, A., (1998). A physical model for porosity reduction in sandstones. Geophysics, 63, 454–459.
Grana, D., (2016). Rock Physics Modeling in Conventional Reservoirs. In New Frontiers in Oil and Gas Exploration, Springer International Publishing, 137-163.
Hamilton, E.L., (1956). Low Sound Velocities in High‐Porosity Sediments. The Journal of the Acoustical Society of America, 28(1), 16-19.
Han, D.H., Nur, A. and Morgan, D., (1986). Effects of porosity and clay content on wave velocities in sandstones. Geophysics, 51(11), 2093-2107.
Hashin, Z. and Shtrikman, S., (1963). A variational approach to the theory of the elastic behaviour of multiphase materials. Journal of the Mechanics and Physics of Solids, 11(2), 127-140.
Kuster, G. T., & Toks€oz, M. N., (1974). Velocity and attenuation of seismic waves in two-phase media. Geophysics, 39, 587–618.
Mavko, G., Mukerji, T. and Dvorkin, J., (2009). The rock physics handbook: Tools for seismic analysis of porous media. Cambridge University Press.
Mindlin, R., (1949). Compliance of elastic bodies in contact: Journal of Applied Mathmatics, 16, 259–268.
Norris, A. N., (1985). A differential scheme for the effective moduli of composites: Mechanics of Materials, 4 (1), 1–16.
Nur, A.M., Mavko, G., Dvorkin, J. and Gal, D., (1995). Critical porosity: The key to relating physical properties to porosity in rocks. In SEG Technical Program Expanded Abstracts, 878-881.
Reuss, A., (1929).Berechnung der fließgrenze von mischkristallen auf grund der plastizitätsbedingung für einkristalle. ZAMM‐Journal of Applied Mathematics and Mechanics/Zeitschrift für Angewandte Mathematik und Mechanik, 9(1), 49-58.
Saul, M.J., (2014). Pressure-dependent elastic properties of sandstones, with applications to seismic reservoir characterisation and monitoring, Ph.D dissertation, The University of Western Australia.
Zimmer, M., (2003). Seismic velocities in unconsolidated sands: Measurements of pressure, sorting, and compaction effects, Ph.D dissertation, Stanford University.
Zimmerman, R. W., (1991) Elastic moduli of a solid containing spherical inclusions: Mechanics of Materials, 12, 17–24. W.H. Freeman & Co.
Journal of Petroleum Geomechanics
Volume 1, Issue 2
December 2017
Pages 74-85

Files

Share

How to cite

Statistics