Multiscale Pore Network Modelling applied to Petrophysical Characterization of Heterogeneous Carbonate Rocks
Mantovani, I. F.1; Moreira, A. C.1; Jiang, Z.2; van Dijke, M. I. J.2; Fernandes, C. P.1
1 Federal University of Santa Catarina; 2 Heriot-Watt University
doi:10.20906/CPS/CILAMCE2017-0768
Resumo
Microstructure system comprehension in porous media is of significance in environmental science and technology, in particular water and hydrocarbon reservoir. In natural materials, such as petroleum reservoir rocks, the morphology and connectivity of the porous system characterization contributes to improvements in hydrocarbons recovery strategies (oil and gas). Advances in X-ray microtomography, which is a non-destructive 3D imaging technique, have enabled us to see the details of the internal structure of rocks. Pore-scale imaging studies have mostly focused on homogeneous porous material such as bead packs and sandstone rocks. Sandstones rocks have been studding for a long time, so its porous structure is well known: usually consisting of rounded grains and a short range of pore size. However, complex carbonate rocks constituting more than 50% of hydrocarbon reserves in the world and represent an important water supplying to one quarter of the global population. Porous system of carbonate is often very complex, with a multiple pore-sized system, from nanometers to millimeters, which requires a multiscale analysis. By extension, we used a pore network modeling of Jiang et al. (2011), which combines two or more networks (in different scales) in order to set the completely sample porous media. The methodology includes data acquisition of two CT images (one in a course scale and another in fine scale) and processing for each sample involved. Results provided insight into absolute permeability in a multiscale analysis and the influence of considered more than one scale to characterize a heterogeneous porous media by means CT images. The features of the carbonate porous system (pore size distributions and porosity) of each scale and the multiscale are presented in order to precede an overview interpretation of the data.
Palavras-chave: Heterogeneous porous media; X-ray computed microtomography; pore network integration; absolute permeability