Microfacies approach to reservoir-related outcrop analogy studies of Wadi Waqb member

This study present a microfacies approach to reservoir-related outcrop analog studies of the exposed discontinuous fringing rhodolith and coral reef complex of Wadi Waqb Member (Miocene Carbonate) of Jabal Kibrit formation in Midyan region, Saudi Arabia. Four facies were recognized as follows: MF-1) Proximal clastic facies comprises of calcallochemic sandstone MF-2) Upper reef front facies characterize by quartz-peloid packstone, and red algal bioclastic boundstone, and MF-3), Lower reef front facies compose of bioturbated rhodophyte-bioclastic grainstone, and MF-4) Fore reef facies comprise of intraclastic wackestone to mudstone. MF-1 represents a mixed carbonate-siliciclastic deposits with very good intergranular porosity preservation in outcrops. However, this porosity does not have any bearing on the Wadi Waqab main reservoir. The preserved primary intergranular and vuggy porosities in MF-2 and MF-3 are considered to be the main components of the Wadi Waqb reservoir. MF-4 possesses no visible porosity in thin section and therefore, does not have any bearing to the main reservoir.