Spatial heterogeneity of carbonate fractured-porous formations from well testing and seismic data

S. G. Volpin^a, I. V. Afanaskin^b, A. K. Ponomarev^a, Yu. M. Shteinberg^a, D. V. Solopov<sup>a

a</sup> Scientific Research Institute for System Analysis of the National Research Centre ”Kurchatov Institute”, Moscow, Russian Federation
^b Almetyevsk State Technological University Petroleum Higher School, Almetyevsk, Russian Federation

Abstract: We studied the spatial heterogeneity of carbonate fractured-porous reservoirs using a comprehensive interpretation of well-test data. Our goal was to evaluate the reservoir's flow and storage properties and to identify high-permeability flow channels. We analyzed pressure build-up tests, pressure fall-off tests, and long-term pressure and rate histories. We interpreted the data by matching calculated and measured curves, and applying Burdine and Blasingame diagnostic plots. We also integrated the well test results with geophysical and seismic data, including duplex wave anomaly maps. The analysis provided quantitative estimates of permeability, diffusivity, skin factor, and distance to flow boundaries. We identified highly fractured zones, which correlated with anomalies on seismic attribute maps. The results show that combining dynamic and geophysical data improves interpretation reliability and helps delineate lateral barriers.

Keywords: hydrodynamic well testing, pressure recovery, pressure drop, long-period curves, wireline logging, porous fractured reservoir, permeability, anisotropy, skin factor, duplex waves, reservoir caprock.