Hydraulic flow unit and facies analysis integrated study for reservoir characterisation: a case study of Middle Jurassic rocks at Khashm El-Galala, Gulf of Suez, Egypt

Abstract

The geological attributes, the nature of permeability barriers, and petrophysical properties are substantial for defining the different hydraulic units which do not necessarily coincide with the geological facies boundaries. The integrated study between facies analysis and classic discrimination of hydraulic flow units is very important to categorise rock quality and heterogeneity as a reservoir. The lithofacies and petrographic microfacies analyses are carried out based on subjective geological observations, whereas the graphical and statistical hydraulic flow unit discriminations are carried out based on permeability-porosity empirical relationships. The reservoir quality heterogeneity is in charge of characterising the hazard in delineating a new discovery in the field. In this study, the authors defined and described five facies (F1, F2, F3, F4 and F5) in light of the geological attributes of the Jurassic rocks at Khashm El-Galala. Facies F5, which is coarse to medium-grained quartz arenite sandstone, represents the best reservoir quality. Three hydraulic flow units (HFU1 through HFU3) were described precisely in the studied rocks with flow zone indicator (FZI) values referring to a wide range of hydraulic characteristics. Quartz constitutes the dominant framework mineral in the sandstone samples. Compaction and cementation are the most effective porosity-reducing diagenetic processes that change the reservoir rock quality.