Petrography image segmentation for analyzing the connectivity of pore networks in Brazilian pre‐salt carbonate rocks of the Barra Velha Formation

This study addresses the challenge of characterizing pore network connectivity within carbonate reservoirs, specifically within the Barra Velha Formation in Brazil's pre-salt deposits. The research aims to determine how effectively digital imaging technology can be used to analyze and quantify the microstructures of these reservoirs. The key questions driving this study are: How well can two-dimensional digital image processing and pore network models capture pores' spatial distribution and connectivity? To what extent do these methods correlate with other petrophysical properties critical to reservoir performance? To answer these questions, we evaluated the petrophysical and geometrical characteristics of the pore system using various distance metrics—Euclidean, Quasi-Euclidean, City-block, and Chessboard—to assess pore connectivity. The study found that while digital image analysis provides valuable insights, its effectiveness depends heavily on the chosen distance metric and the specific properties of the carbonate reservoir. The results suggest that the Euclidean and quasi-Euclidean metrics are more reliable for capturing connectivity in these settings, offering clues for better understanding fluid dynamics and improving exploration and extraction strategies. However, the study also reveals limitations in the digital approach, particularly in its ability to fully capture the complexity of the pore network. These findings confirm the relevance of digital imaging but also underscore the need for more advanced methods or complementary techniques to achieve a more accurate characterization of carbonate reservoirs.