Pore Structure Characterization of Indiana Limestone and Pink Dolomite from Pore Network Reconstructions

Abstract

-Carbon sequestration in deep underground saline aquifers holds significant promise for reducing atmospheric carbon dioxide emissions (CO 2 ). However, challenges remain in predicting the long term migration of injected CO 2 . Addressing these challenges requires an understanding of pore-scale transport of CO 2 within existing brine-filled geological reservoirs. Studies on the transport of fluids through geological porous media have predominantly focused on oil-bearing formations such as sandstone. However, few studies have considered pore-scale transport within limestone and other carbonate formations, which are found in potential storage sites. In this work, high-resolution micro-Computed Tomography (microCT) was used to obtain pore-scale structural information of two model carbonates: Indiana Limestone and Pink Dolomite. A modified watershed algorithm was applied to extract pore network from the reconstructed microCT volumetric images of rock samples and compile a list of pore-scale characteristics from the extracted networks. These include statistical distributions of pore size and radius, pore-pore separation, throat radius, and network coordination. Finally, invasion percolation algorithms were applied to determine saturation-pressure curves for the rock samples. The statistical distributions were comparable to literature values for the Indiana Limestone. This served as validation for the network extraction approach for Pink Dolomite, which has not been considered previously. Based on the connectivity and the pore-pore separation, formations such as Pink Dolomite may present suitable storage sites for carbon storage. The pore structural distributions and saturation curves obtained in this study can be used to inform core-and reservoir-scale modeling and experimental studies of sequestration feasibility.Résumé -Caractérisation de la structure de pore de l'Indiana limestone de calcaire et de Pink dolomite provenant des reconstitutions de réseaux de pores -La séquestration du carbone dans les aquifères salins profonds souterrains est très prometteuse pour la réduction des émissions de dioxyde de carbone (CO 2 ) dans l'atmosphère. Cependant, des problèmes demeurent dans la prédiction de la migration à long terme du CO 2 injecté. Relever ces défis nécessite une compréhension du transport de CO 2 à l'échelle du pore dans des réservoirs géologiques existants remplis de saumure. Les études sur le transport des fluides en milieu poreux géologique ont principalement porté sur les formations oléagineuses telles que le grès. Cependant, peu d'études ont

Hydrophilic and Hydrophobic Characteristics of Reservoir Rocks Quantified by Nuclear Magnetic Resonance-Detected Water Isotherms

“…19 The porosity of Indiana limestone typically ranges from 12 to 18%. 20,21 Regardless of those research data, the higher porosity in the carbonate reservoir rock can be distinguished easily in the lab. The inset figures in Figure 7a are photos of the cross sections of carbonate reservoir rock (left) and Indiana limestone (right), respectively.…”

“…Alsharhan and Magara found that the carbonate reservoir rocks in the Middle East show exceptionally high porosity up to 30%, which makes the Arabian Gulf one of the most prolific oil fields in the world . The porosity of Indiana limestone typically ranges from 12 to 18%. , Regardless of those research data, the higher porosity in the carbonate reservoir rock can be distinguished easily in the lab. The inset figures in Figure a are photos of the cross sections of carbonate reservoir rock (left) and Indiana limestone (right), respectively.…”

Pore Structure Characteristics and Permeability Prediction Model in a Cretaceous Carbonate Reservoir, North Persian Gulf Basin

“…In rocks, both large pores and small pores are connected with each other, and the only difference is how good the connectivity is. Diffusion coupling is a phenomenon in which fluid molecules are diffused between large and small pores, and it results in the uniformization of the T 2 spectrum [63][64][65][66]. Some scholars believe however that the diffusion coupling effect invalidates the method used to calculate the movable water saturation through the T 2cut-off value [23,25].…”

Multi-scale Image-Based Pore Space Characterisation and Pore Network Generation: Case Study of a North Sea Sandstone Reservoir

“…Many carbonate systems also have a wide range of pore sizes (Youssef et al 2007;De Boever et al 2012;Freire-Gormaly et al 2015). Typically, these porous media exhibit multiple porosity and multi-modal pore size distributions, e.g.…”