Characterization and analysis of naturally fractured gas reservoirs based on stimulated reservoir volume and petro-physical parameters

Fracture is one of the most important geological phenomena that affect the production of hydrocarbon compounds in broken carbonate reservoirs. However, fracture controlling factors must be combined with well data to achieve accurate fracture modeling. Therefore, structural data, drilling data, well flow diagrams, cores data, wells production data, and dynamic reservoir data have been considered here. Finally, by combining the above-mentioned information and through statistical and mathematical methods, the mechanism of fracture creation, general trends, and dominant fracture patterns are determined. These patterns are directly related to the tectonic regime and the stresses governing the region. For the first time, in this paper, we divided Zubair carbonate gas reservoir into 10 zones based on porosity and water saturation, and shale volume variation. We conclude that just four-zone of these are economic producible. Besides, the dominant lithology of this formation is more than limestone and a small number of thin shale layers. We defined types of cross-sectional petro-physical graphs and confirmed them by the geological graphic diagram prepared at the head.

Automated summary

This study analyzed the mechanism, trends, and patterns of fracture formation in carbonate reservoirs through combining various types of data and using statistical and mathematical methods for fracture modeling. Economic producible zones were identified in the Zubair gas reservoir, with the dominant lithology being limestone and thin shale layers.