Carbonate rocks constitute as much as 19-22% of the sedimentary rock records while they account for approximately 50% of oil and gas production worldwide. These types of sedimentary rocks can form from biological, biochemical, and/or inorganic precipitation of CaCO3 from sea water, and can appear as reservoir rocks, intermediate layers or even reservoir seals. Carbonates as reservoir rocks are generally complex, and difficult to model, and even the correlation between their velocity, and porosity or even density is normally highly scattered. This scattered pattern is a result of the high petrophysical heterogeneity in their matrix which can be attributed to their forming process.
Therefore, rock physics modeling in carbonate rocks can be more challenging, and uncertain compared with the siliciclastics due to the high heterogeneity in their geological and petrophysical properties. This uncertainty in the carbonates elastics prediction normally is attributed to their complex and highly variable pore structure. This in turn can introduce more uncertainty within the seismic characterization methods. Therefore, establishing a reliable link between pore geometry changes, and velocity variations within carbonate rocks can assure for a better characterization results. As a matter of fact, pore structure in carbonate is the result of the place they are deposited combined with the subsequent post-depositional processes to form the final carbonate rock. This combination along with their chemically active mineralogy makes them susceptible for complex, and heterogeneous pore structures. One of the major challenges in the carbonate seismic characterization is establishing a quantitative link between such a highly variable pore geometry and elastic properties. There have been various effort to model carbonate pore structure and using inclusion based models is one of the suggested approaches for this purpose. These type of models assume pore space as an idealized ellipsoid, and include them into an effective matrix using scattering theory. This presentation investigates different modeling approaches to capture pore structure variations in carbonates using all of the available data including geological information. These approaches attempt to quantify a more comprehensive pore model for carbonate rocks, which furthermore, can assist with a more accurate results on different characterization methods. Different case studies will be presented and discussed to show the applicability of such approaches on different carbonate reservoirs.
- Speaker: Mohammad Reza Saberi, CGG
- Moderator: Beth Rees, CGG
- Regional Timings: 5:00 PM UAE | 4:00 PM KSA | 3:00 PM EGY
Mohammad Reza Saberi
Mohammad Reza Saberi is the product development manager for rock physics at CGG GeoSoftware. At CGG, he is affiliated with the rock physics development team to make a comprehensive and central rock physics module to support the required rock physics analysis and modeling as well as rock physics centeral workflows for different characterization projects. Reza received a PhD in geophysics and rock physics from the University of Bergen in 2010, and has been working in the upstream part of oil and gas industry for about 20 years. He has worldwide experiences in E&P projects in different roles as geophysicist and geoscientist, project manager, technical product manager and team manager and has been actively involved in different R&D projects and scientific publications.