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Utilizing advanced seismic techniques for delineating hydrocarbon accumulations in HST (High Stand System Tract) turbidite channel of Kafr El-Sheikh (KS) formation (Pliocene Age) located in the western part of South Batra field (SBF), Nile Delta – Egypt is investigated. 3D seismic data and four well logs helped in studying the properties of the channel. Three wells encountered the central part of the channel and showed thicker reservoir thickness than the fourth well, which encountered the levee. The channel is characterized by high porosity (25–30%) and relatively low water saturation (27–50%). The structural map showed that the channel is dipping towards the NE–SW. AVO analysis, scaled Poisson’s ratio, post-stack seismic inversion, and seismic attributes confirmed the presence of Class III gas sand. Variance attribute helped in imaging the channel and faults. Maps generated from spectral decomposition showed that the dominant frequency is around 15 hertz. Results of integrating different techniques were consistent and successfully helped in determining the geometry of the channel, discriminating between different lithologies and fluids, in addition to delineating the sweet spots and recommended locations for drilling. [ABSTRACT FROM AUTHOR]

Following recent hydrocarbon exploration activity, a new study has been carried out with the goal of defining the high-resolution biochronologic sequence stratigraphy of the Oligocene section in the offshore Nile Delta. A total of 98 samples were selected from 2 wells: Burullus 1 Memphis and Petrobel 1 Habbar. The study is based on a high-resolution microfossil biochronology including benthic and planktonic foraminifera and nannofossils as well as facies analysis and wire-line log calibration to investigate the evolution of Oligocene gas-bearing sequences in the southeastern Mediterranean region. The planktonic-benthic ratio, foraminiferal diversity, and upper depth limit of benthic foraminiferal taxa as well as the abundance of calcareous nannoplankton help in interpreting the depositional paleoenvironments of the Oligocene succession as fluvial, shallow-marine, middle- to outer-shelf, and bathyal domains. Six sequences were identified, three of which are lower Oligocene (Rupelian) (RuSeql, RuSeq2, and RuSeq3), and the others are upper Oligocene (Chattian) (ChSeq4, ChSeq5, and ChSeq6). The sequence boundaries and flooding surfaces were correlated with the global eustatic sea-level models. Three major breaks--Eocene-Oligocene, lower-upper Oligocene, and upper Oligocene-lower Miocene boundaries--with intraformational breaks were well defined. [ABSTRACT FROM AUTHOR]

A high-resolution quantitative nannoplankton biostratigraphy has been established in four wells based on a total of 1241 subsurface samples to understand and improve hydrocarbon exploration and recovery in the offshore Nile Delta. Ninety-two nannofossil species were used to delineate stages/ages boundaries of the Miocene-Pleistocene succession and to construct the age-depth model. Empirical, semi-quantitative (Graphic Correlation), and quantitative (Unitary Associations 'UA') methods retained comparable results, suggesting that the data quality is a master variable in the biostratigraphic resolution of the studied sequence. The UA method retained a sequence of 22 UAs, which exceeded the empirical zones (15; CNM6-CNPL9 = NN4-NN19). However, these UAs were merged into 14 zones (UAZ) to enable correlation among sections. Age-depth models and the nannofossil abundance were used to estimate the sedimentation rates and identify the system tracts within the depositional cycles. The variation in sedimentation rate was attributed to the interplay between the sea level and Nile flooding, which controlled the terrigenous influx. Furthermore, the nannofossil diversity was linked to the sequence stratigraphic framework, where seven 3rd order sequences were identified and correlated with the Global Tethyan sequences. Moreover, the extinction rate has increased after the Messinian and is attributed to the Pliocene-Pleistocene sea-level highstand and invasion of deeper water rich in nutrients from the upwelling zone. • 92 nannofossil species in 1241 samples were quantitatively analyzed in four wells. • 15 biozones (CNM6 to CNPL9) in the Miocene-Pleistocene of the offshore Nile Delta. • Empirical zonation, Graphic Correlation, and Unitary Association retained comparable results. • Higher nannofossil diversity was associated with lower sedimentation rate and higher sea-level. • Extinction rate has increased after the Messinian due to invasion of deeper water. [ABSTRACT FROM AUTHOR]