Beni Suef Basin Research Articles

Facies controls and tectonic evolution on oil accumulation and entrapment in the Cenomanian Abu Roash G member, northern-central Egypt: Deltaic and channel sandstones as good reservoirs

Along northern-central Egypt, the oil accumulation and entrapment were mainly controlled by variable parameters including the stratigraphic architecture, sedimentary features, and tectonic evolutions. The present paper presents a new model for oil occurrences in the Abu Roash G Member (Cenomanian) along Gindi, Abu Gharadig and to a few extents the Beni Suef basins, in the northern-central part of the Western and Eastern Deserts of Egypt. The studied concessions include the Wadi El Rayan, East Bahariya and El Diyur (Gindi basin and Abu Gharadig basins, Western Desert) and the Ghariboun (Beni Suef Basin, Eastern Desert) fields. Twenty sedimentary facies were recorded from the studied subsurface sections of the Abu Roash G Member and grouped into three facies associations. A new depositional model is achieved where estuarine, open marine, deltaic distributaries, and tidal channel deposits are the main facies associations recorded in the studied Abu Roash “G". These deltaic and channel deposits occurred as an arch like form between open marine and estuarine deposits. These deltaic and tidal channel sandstone deposits act as a good reservoir to accumulate oil from nearby areas. As well, these areas were subjected to the well-known Syrian arch compressional deformation that affected northern Egypt during the Mesozoic, up to late Senonian time. A regional NE-SW oriented fold system took place, forming NE-SW oriented ridges in addition to the dextral strike-slip movement that took place along these ridges because of this compressional deformation.To sum up, oil accumulation in the studied Abu Roash G Member was mainly controlled by facies distribution mainly of channel sandstone enhanced by the tectonic movements (Syrian Arc System) affecting the areas studied.

Petroleum system assessment of the Beni Suef Basin, Western Desert, Egypt

Within the northwestern Desert of Egypt, the Beni Suef Basin is one of the most significant hydrocarbon basins. After over 50 years of exploration and production, the main challenge today is to locate new areas that are prolific to oil and gas production. The study aims to identify potential drilling locations by integrating geochemical methods, 1D and 2D basin modelling, well log analysis, seismic interpretation, and hydrocarbon migration pathways. Results show that the Lower Kharita shale contain both oil and gas generating kerogen with generating potential that ranges from fair to very good. The source rocks within the Lower Kharita are mature (main oil window) and have a transformation ratio of up to 60% based on 1D basin modeling. The modelled 2D vitrinite reflectance map showed that hydrocarbon generation occurred at depths greater than 10850 ft (3306 m) with vitrinite reflectance values greater than 0.65% in both the northern and southern parts of the Beni Suef Field. Two main reservoirs were studied. The lower Bahariya and upper Kharita reservoirs are composed of well to moderately sorted sandstone. The subsurface structural maps, reservoirs, source, and charge modeling maps have been constructed to show the migration pathways and accumulation areas. There are three accumulation areas identified. The first accumulation area is located in the high structure up-dip section of the major normal fault, and migration direction is from northwest. The second and third accumulation areas are located in the low structure and down-dip from the normal fault, with migration of hydrocarbons from southeast. The latter two areas should be tested by drilling in the future.

Geochemical evaluation and basin modelling of the Cretaceous succession in the Azhar Oil field, West Beni Suef Basin, Egypt

Geochemical analysis was performed on the Cretaceous sequence of the Azhar‐A‐2 well in the West Beni Suef Basin (WBSB), Western Desert, Egypt, utilizing data on total organic carbon (TOC), kerogen composition, vitrinite reflectance (Ro%) and Rock‐Eval pyrolysis. In addition, a 1D basin model was built to investigate the burial and temperature history of the study area. The most important Cretaceous source rocks are predominantly reported within the Albian Kharita Formation and Late Cenomanian‐Santonian Abu Roash (AR) Formation. Based on visual kerogen tests and Rock‐Eval pyrolysis, AR Formation (A, E, F, and G) are mixed oil‐ and gas‐prone source rocks with kerogens ranging from type II to type III, where A/R ‘A and F’ Members show dominant oil‐prone kerogen with the highest generative potential, while A/R ‘E and G’ Members are more gas‐prone kerogen. Most samples of the lower Kh Formation were interpreted as gas‐prone kerogen type III with low generative potential. On the other hand, the high amount of liptinite in the visual kerogen macerals is a strong indicator that the lower Petroleum Formation is an oil‐prone rather than gas‐prone source rock. The thermal maturity of the studied members increases consistently with depth, ranging from immature at the top of the AR Formation to the main/peak oil window at the base of the Lower Kharita Formation, which served as an active source rock for the hydrocarbons generated in the WBSB. The high value of the heat flow in the Beni Suef Basin (57 and 60 mW/m2) is a good indicator for the shallowing of the active source rock depth limit depth. From the study of the basin modeling, the main mature zone reached between 9811 and 11,090 ft in the middle of the Late Cretaceous (84.3–82.5 Ma) is through the L. Kharita Formation with three phases of hydrocarbon generation according to transformation ratio, where the second phase is the main stage in which TR is 5%–50%, showing the beginning of oil expulsion (Ro: 0.73%–0.78%, possibly 0.81%).

Petrophysical and Gas Chromatographic Analysis Integration for Hydrocarbon Identifications in Cretaceous Reservoirs, Azhar Field, Beni Suef Basin, Egypt

Petrophysical and Gas Chromatographic Analysis Integration for Hydrocarbon Identifications in Cretaceous Reservoirs, Azhar Field, Beni Suef Basin, Egypt

Hydrocarbon gas chromatography as indicator of fluids types: A case study of Azhar field, Beni Suef Basin, Egypt

Hydrocarbon gas chromatography as indicator of fluids types: A case study of Azhar field, Beni Suef Basin, Egypt

The Upper Cretaceous petroleum system of the East Beni Suef Basin, Egypt: an integrated geological and 2D basin modelling approach

We integrated geological and 2D basin modelling to investigate the tectonostratigraphic evolution of the East Beni Suef Basin (EBSB) of north central Egypt and its implications for the Upper Cretaceous petroleum system. Two intersecting seismic sections and three exploration wells were used for this study. The geological model defines the structural and geometrical framework of the basin, which formed the basis for subsequent 2D basin modelling. The developed basin models were calibrated and fine-tuned using vitrinite reflectance and corrected temperature data. Modelling results indicate that the Abu Roash ‘F’ source-rock maturity ranges from the early oil window at the basin margins to the main oil window in the centre. The main phase of hydrocarbon generation occurred during the Eocene after trap formation in the Late Cretaceous. Generated hydrocarbons have migrated both laterally and vertically, most likely from the central part of the basin towards the basin margins, particularly eastwards to the structural traps. The model predicts low accumulation rates for the EBSB, which are caused by the ineffective sealing capacity of the overburden rocks and normal faults. In addition to the proven kitchen for the charging of the Abu Roash ‘E’ reservoirs, an additional kitchen area to the NW of the basin is suggested for the Abu Roash ‘G’ reservoirs.

Geophysical assessment for the oil potentiality of the Abu Roash “G” reservoir in West Beni Suef Basin, Western Desert, Egypt

The current study evaluates the hydrocarbon potentiality of the sandstone intervals of the Abu Roash “G” Member in Beni Suef Basin, Egypt. This evaluation has been performed through seismic interpretation for thirty seismic profiles and petrophysical appraisal for Fayoum-2X well (Fayoum oil field) and Yusif-4X well (Yusif oil field). The seismic interpretation presented the prevalence of the Lower Cretaceous NW-SE normal faults followed and linked with a major Late Cretaceous ENE strike-slip fault affected the Beni Suef Basin. This strike-slip fault is accompanied by a significant flower structure and releasing bend in the middle part of the studied area. The entrapment styles in both Fayoum and Yusif oil fields are considered by the existence of NW-SE trending horst closures bounded by the NW-SE faults. The petrophysical analysis exhibits good reservoir quality for the sandstones of Abu Roash “G” Member in the examined fields with low shale volume (5–20%); high effective porosity (15–25%), relatively low water saturation (35–55%) and pay thickness varies between 14 ft and 16 ft. Although the Abu Roash “G” Member exhibits lateral facies changes across the Beni Suef Basin, this study highlights the hydrocarbon potentiality of its entire sandstones for further exploration and development purposes in both Fayoum and Yusif oil fields. Core-based petrophysical analysis and detailed sedimentological analyses for the reservoir zones within Abu Roash “G” Member at Beni Suef Basin are highly recommended to emphasize the effect of the lateral facies change on the reservoir properties along the whole basin which will affect the development plans. The integration of multiscale datasets which includes seismic, different types of well logs, core is giving a precise picture about the reservoir units. Altogether are figuring out the detailed composition of reservoir sedimentology and quality by using the core information, investigate the hydrocarbon potentiality using the well logging evaluation, deducing their trapping mechanism, and controlling structures using the seismic datasets and the spatial distribution is define based on the correlation between different wells, depositional and structural conditions.

Seismic interpretation and hydrocarbon assessment of the post-rift Cenomanian Bahariya reservoir, Beni Suef Basin, Egypt

The geophysical interpretations for a collection of high-quality 2D seismic data plus well logging data for six drilled wells exposed the structural controls and the hydrocarbon potentiality of the Beni Suef Basin, north Western Desert, Egypt. The created structural map on the top of the Early Cenomanian Bahariya Formation (the significant oil reserve in north Western Desert), exhibits a series of NW–SE normal faults as well as a master ENE strike-slip major fault. The extensional faults formed horst structures while the strike-slip fault created a negative flower structure in the central part of the study area. These structural features represent the main petroleum traps within Beni Suef Basin. The reservoir quality was assessed through the petrophysical analysis of the Bahariya Formation in wells; Azhar A2, Azhar E-2X, Azhar E3, Yusif-4X, Fayoum-2X and Beni Suef W-1X. This analysis proved that the Lower Bahariya unit has better reservoir quality than the Upper Bahariya reservoir, with shale volume less than 10%; effective porosity between 10 and 20%, water saturation between 25 and 75% and total pay thickness between 11 and 88 ft. The obtained results encourage drilling more exploratory wells in Beni Suef Basin to enhance the productivity from the sandstones of the Lower Bahariya reservoir.

Tectonic evolution and subsidence history of the Cretaceous basins in southern Egypt: The Komombo Basin

AbstractThe structure and tectonic evolution of the Cretaceous rift basins of southern Egypt are poorly understood. In this study, the tectonostratigraphy of the Komombo Basin has been determined using seismic, well and biostratigraphic data. The tectonostratigraphy of the basin is compared to the Kharit, Nuqra and Beni Suef basins in Egypt as well as Muglad Basin in Sudan. The Komombo Basin is a 58 km long, 28 km wide NW–SE trending half‐graben infilled with 2200 m of Berriasian‐Maastrichtian sediments and overlain by 400 m of Pliocene sediments. Four Berriasian to Maastrichtian syn‐rift and post‐rift sequences and three Pliocene channel systems of Nile sediments have been identified. Moreover, a series of normal faults, negative flower structures, reverse faults and folds are mapped in the basin. Backstripping reveals two rift phases during the Berriasian‐Barremian and Turonian‐Santonian, respectively. Additionally, the tectonic subsidence curves indicate that two major unconformities have occurred during the Aptian‐Albian and Maastrichtian‐Pliocene, which are correlated with a basement uplift during the Albian‐Cenomanian and the Oligocene‐Miocene flank uplift related to the opening of the Red Sea, respectively. The rift episodes are attributed to far‐field stress changes resulting from the initial opening of the South Atlantic and followed by the NW part of the African plate colliding and anticlockwise rotating into Europe. The highest β factors (1.20–1.11) for both rift phases are found at the centre of the basin. The rift phases thinned the crust from 32.5 to 28.2 km and 31.9 km in the depocenter and the western flank of the basin. The Komombo Basin has a similar rift history, stratigraphy and structural style to the Kharit, Nuqra and Mugland basins. All of these basins witnessed two major rift phases in the Early and Late Cretaceous, whereas the Beni Suef Basin encountered strike‐slip tectonic events in the Late Cretaceous.

Source rock evaluation and petroleum system modeling of the East Beni Suef Basin, north Eastern Desert, Egypt

This study deals with the East Beni Suef Basin (Eastern Desert, Egypt) and aims to evaluate the source-generative potential, reconstruct the burial and thermal history, examine the most influential parameters on thermal maturity modeling, and improve on the models already published for the West Beni Suef to ultimately formulate a complete picture of the whole basin evolution. Source rock evaluation was carried out based on TOC, Rock-Eval pyrolysis, and visual kerogen petrography analyses. Three kerogen types (II, II/III, and III) are distinguished in the East Beni Suef Basin, where the Abu Roash “F” Member acts as the main source rock with good to excellent source potential, oil-prone mainly type II kerogen, and immature to marginal maturity levels. The burial history shows four depositional and erosional phases linked with the tectonic evolution of the basin. A hiatus (due to erosion or non-deposition) has occurred during the Late Eocene-Oligocene in the East Beni Suef Basin, while the West Beni Suef Basin has continued subsiding. Sedimentation began later (Middle to Late Albian) with lower rates in the East Beni Suef Basin compared with the West Beni Suef Basin (Early Albian). The Abu Roash “F” source rock exists in the early oil window with a present-day transformation ratio of about 19% and 21% in the East and West Beni Suef Basin, respectively, while the Lower Kharita source rock, which is only recorded in the West Beni Suef Basin, has reached the late oil window with a present-day transformation ratio of about 70%. The magnitude of erosion and heat flow have proportional and mutual effects on thermal maturity. We present three possible scenarios of basin modeling in the East Beni Suef Basin concerning the erosion from the Apollonia and Dabaa formations. Results of this work can serve as a basis for subsequent 2D and/or 3D basin modeling, which are highly recommended to further investigate the petroleum system evolution of the Beni Suef Basin.

Reservoir characterization of the Upper Cretaceous Abu Roash ‘G’ Member, using 3-D seismic data in the WON-X Oil Field, Beni Suef Basin, Western Desert, Egypt

The WON-X field was discovered in the western area of Beni Suef Basin in Egypt, which is now being explored and exploited in the part of the northern Desert. Within this concession, the WON-X field is adopted to producing hydrocarbons successfully. The West Beni Suef basin is one of the prospective area recently added to Egypt's oil exploration strategy (WON-X). Interpolated seismic data oriented NE-SW and passed through well faults displayed the element that impacted the research area. The Lower Cretaceous Albian Kharita Fm, superimposes the foundation rocks in an unconformable form. The original Nile was at the top of the seismic section, where the sediments were eroded in a variety of methods, until they reached the Abu Roash E (A/R E) Member. It was feasible to find major lateral changes in the reservoir, such as stratigraphic barriers, as a result of many drilled wells evaluated, including pressure measurements, which differed between the southern and northern portions of the field. Through the integration of seismic and geological well log data, the WON-X oil field has obtained extensive knowledge and a deeper understanding of the potential of the Abu Roash (AR "G") reservoir. Seismic attributes such as the RMS map can be utilized, to discover various compartments in the field and the other geologic factors whose, amplitude responses allow them to be separated from the background features. In addition, the RMS map depicts the stratigraphic mud barrier that developed between the wells in the studied area. In addition to normal fault lines, the WON-X hydrocarbon oilfield is located on a doubly plunging anticline, commonly referred to as an "asymmetrical anticline." According to the maps of the AR "G" reservoir, this anticline's centre is a prime place for oil accumulation.

Reservoir characterization of the Upper Cretaceous Abu Roash "G" Member, using wire line logs and 3D seismic data in West of Nile-X Field, Beni-Suef Basin, Western Desert, Egypt.

Reservoir characterization of the Upper Cretaceous Abu Roash "G" Member, using wire line logs and 3D seismic data in West of Nile-X Field, Beni-Suef Basin, Western Desert, Egypt.

Geochemical characterization of the source rock intervals, Beni-Suef Basin, West Nile Valley, Egypt

Abstract Geochemical and lithological investigations in the WON C-3X well record five organic-matter-rich intervals (OMRIs) of effective source rocks. These OMRIs correspond to moderate and good potentials. Two of these intervals occurred within the L-Kharita member of the Albian age represent 60.97% of the entire Albian thickness. The rest of OMRIs belongs to the Abu-Roash G and F members of the Late Cenomanian–Santonian age comprising 17.52 and 78.66% of their total thickness, respectively. The calculated heat flow of the studied basin is high within the range of 90.1–95.55 mW/m2 from shallower Abu-Roash F to deeper L-Kharita members. This high-heat flow is efficient for shallowing in the maximum threshold expulsion depth in the studied well to 2,000 m and active source rock depth limit to 2,750 m. Thermal maturity and burial history show that the source rock of L-Kharita entered the oil generation from 97 Ma till the late oil stage of 7.5 Ma, whereas the younger Abu-Roash G and F members have entered oil generation since 56 Ma and not reached peak oil yet. Hence, the source rock intervals from Abu-Roash F and G are promising for adequate oil generation.

Neural network application to petrophysical and lithofacies analysis based on multi-scale data: An integrated study using conventional well log, core and borehole image data

Application of artificial neural network (ANN, e.g., Multi-layer perceptron, MLP) became widespread in the petroleum industry, especially in formation evaluation, reservoir characterization and modeling studies. In this study, the MLP technique is applied to estimate the lithofacies and petrophysical parameters including permeability and rock typing for the upper unit of Abu Roash G reservoir (ARG), Azhar field in Beni Suef basin. Major steps of the workflow started with lithofacies analysis using core and borehole image data to identify five lithofacies as follows; bioturbated mudstone, lenticular-bedded siltstone, massive laminated sandstone, flaser bedded sandstone, and faintly laminated sandstone, which were deposited in tidal conditions. A fully connected neural network was trained and tested on data for lithofacies prediction in wells with no core data and borehole image. Core permeability was estimated by using different variables including effective porosity, bulk density, volume of shale and volume of sand, it was found that neural network prediction for permeability was very satisfactory and can be applied on wider scale in other uncored wells. Rock typing was constructed in cored wells using several methods including porosity-permeability plot integrated with the Winland R35, flow zone indicator-reservoir quality index (FZI-RQI). Neural network classification method was trained and tested on data for rock type estimation in the uncored zones based on calculated petrophysical log data including permeability, flow zone indicator, reservoir quality index and effective porosity. To get more accurate predicted data, the log data was calibrated firstly using porosity and permeability core data.

Senonian platform-to-slope evolution in the tectonically-influenced Syrian Arc sedimentary belt: Beni Suef Basin, Egypt

The Beni Suef Basin is a rift basin that was formed in the Early Cretaceous in response to the break-up of the Gondwana. The infill consists of a thick Mesozoic–Paleogene succession deposited during two main tectonic phases; the Early Cretaceous syn-rift phase and the Late Cretaceous post-rift phase. The post-rift phase was subsequently subjected to an intense compressional tectonic regime related to late Cretaceous Syrian arc tectonics. Within the basin-fill succession, the Senonian deposits, which are composed of carbonates and mixed siliciclastic/carbonate rocks of the “B” and “A” members of the Abu Roash Formation, was formed as a marine platform developed under fluctuated shelfal conditions. These deposits were overlain by chalk of the Khoman Formation that is interpreted to have formed in an outer shelf–middle slope setting. The Senonian succession is subdivided into two 3rd order depositional sequences (Latest Turonian–Early Coniacian SQ-1 and Coniacian–Santonian SQ-2) and one 2nd order depositional sequence (Campanian–Maastrichtian SQ-3). The depositional history of the Senonian in the Beni Suef Basin is interpreted to have been controlled by variable sedimentation accompanied by progradation and retrogradation of carbonate platform between inner and outer shelf environments during the Coniacian–Santonian, and between inner shelf and upper slope environments during the Campanian–Maastrichtian to the end of Senonian. The changes in depositional environments and relative sea-level fluctuations were a factor of the variations in accommodation and sedimentation likely controlled primarily by the Syrian Arc tectonic pulses, which may also have affected basin development and that of the surrounding areas over the northern Western Desert of Egypt particularly during Senonian.

First Palynological Record from the Upper Carboniferous/Lower Permian Succession in West Beni Suef Basin, Egypt, with Paleoecological and Paleogeographical Implications

FOR THE FIRST time, a palynological assemblage was recovered from the Safi Formation in the west Beni Suef Basin of the Western Desert in Egypt. A total of 65 miospore taxa were recognized; they included 31 species of pteridophyte spores (related to 20 genera) and 34 species of gymnosperm pollen (related to 14 genera). The dominance of monosaccate pollen confirms an age not older than Westphalian (Late Carboniferous) as documented in various Gondwanan basins. Besides the restricted presence and limited counts of typical guide taeniate bisaccate and non-taeniate bisaccate pollen in the present assemblage constrain and limit the age to the Asselian (Early Permian) and not younger. The paleovegetation of the studied palynoassemblage is reconstructed based on the paleobotanical affinities of the identified miospores, which are generally consistent with other macrofloral fossil records obtained from Egyptian outcrops during the Late Carboniferous and Early Permian. The paleoecological significance of the reconstructed paleovegetation enabled the recognition of two paleofloral communities: A lowland paleoflora represented by a cold climate wetland fern community associated with Lycopsida and Sphenopsida and an upland paleoflora dominated by a primitive group of gymnospermic plants with a unique moisture-independent reproduction strategy developed under the influence of a glacial climate. The high representation of the bilaterally or radially symmetrical monosaccate pollen genera, which are typical Late Paleozoic Gondwanan gymnospermic vegetation, in the present material supports the hypothesis that Egypt’s Western Desert was part of the Gondwanan floral province during the Late Carboniferous/Early Permian.

Superposed tectonic regimes in west Beni Suef basin, Nile Valley, Egypt: Implications to source rock maturation and hydrocarbon entrapment

The present study contributes to the knowledge of the structural architecture and kinematic evolution of the West Beni Suef basin, by means of detailed seismic interpretation. This basin is one of several in a NW–SE oriented Early Cretaceous basin system occurring at the northeast corner of the African plate. We used the patterns of growth sedimentation above the limbs of growth folds, and in the downthrows of normal faults as kinematic indictors. Two phases of strike slip tectonics during the Santonian and Campanian–Maastrichtian superposing an Early Cretaceous rifting are verified in this basin. The Santonian and Campanian–Maastrichtian strike slip tectonics are represented by an E–W strike slip fault zone associated with NE growth folds and NW growth normal faults as well as ENE, WNW and E–W strike slip fault segments. The Early Cretaceous rifting facilitates the maturation of the deeper source rocks such as Lower Cretaceous shales of the Kharita Formation. Moreover, the strike slip tectonic events played a major role in the maturation of the shallow depth Cenomanian–Turonian Abu Roash “F” Member through entrapment in a releasing bend at the central part of the study area. The structures associated with the two tectonic regimes include, horsts, normal fault propagation folds and strike slip related anticlines, which formulated the main structural traps in the study area.

Cenomanian–Turonian depositional history of a post–Gondwana rift succession in the West Beni Suef Basin, Egypt

The structural and stratigraphic evolution of rift basins has been documented globally from modern systems, outcrop and subsurface datasets. Extensive fragmentation and break-up of Gondwana during the Cretaceous created a complex suite of rift basins in the Northern Africa. The Beni Suef rift basin straddles the River Nile and is infilled by a thick Mesozoic–Tertiary succession. Cenomanian–Turonian deposition commenced with the sandstone-dominated Bahariya Formation. Depositional environments transitioned stratigraphically from fluvial-marine to shallow marine and finally to mixed clastic and non-clastic shelfal deposits of the Abu Roash Formation. Sedimentation styles were tectonically controlled showing transgressive-to-regressive depositional cycles developed over the Gondwana rift systems. Cycles were controlled by short-lived, small-scale tectonic oscillations of the platform, resulting in four depositional sequences. Deposition environments in the Cenomanian transitioned from shallow marine to deeper marine shelfal deposits and finally to a coastal environment. During Late Cenomanian–Early Turonian, rapid platform submergence resulted in a transgressive facies succession, topped by deltaic deposits. In the Middle–Upper Turonian, two sequences formed with an intervening short-lived period of lower relative sea level. Relative sea-level oscillations were partly in phase with the global sea-level changes, controlled by local tectonics induced by the fragmentation of Gondwana during the Late Cretaceous.

Sequence stratigraphic evolution of the syn-rift Early Cretaceous sediments, West Beni Suef Basin, the Western Desert of Egypt with remarks on its hydrocarbon accumulations

The Beni Suef Basin is a petroliferous rift basin straddling the River Nile containing a thick Mesozoic–Paleogene succession. The Kharita Formation is formed in the syn-rift phase of the basin formation and is subdivided into the Lower and Upper Kharita members. These two members are regarded as two third-order depositional sequences (DSQ-1 and DSQ-2). The lowstand systems tract (LST-1) of the DSQ-1 is represented by thick amalgamated sandstone bodies deposited by active braided channels. Mid-Albian tectonic subsidence led to a short-lived marine invasion which produced coastal marine and inner-shelf facies belts during an ensuing transgressive systems tract (TST-1). At the end of the mid-Albian, a phase of tectonic uplift gradually rose the continent creating a fall in relative sea level, resulting in deposition of shallow marine and estuarine facies belts during a highstand systems tract (HST-1). During the Late Albian, a new phase of land-rejuvenation commenced, with a prolonged phase of fluvial depositional. Fluvial deposits consisted of belts of amalgamated, vertically aggraded sandstones interpreted as braided and moderately sinuous channels, in the lower part of the Upper Kharita Member lowstand stage (LST-2). The continuous basin filling, coupled with significant lowering in the surrounding highlands changed the drainage regime into a wide belt of meandering river depositing the transgressive stage (TST-2). The history of the Kharita Formation finalized with a Cenomanian marine transgressive phase. Economically, the TST-1 and HST-1 play a significant role as source rocks for hydrocarbon accumulations, whereas LST-2 act as good reservoir rocks in the Early Cretaceous in the Basin.

Reply to the comment of Anan et al. on "Palynological, palaeoenvironmental and sequence stratigraphical analyses of a Turonian-Coniacian sequence, Beni Suef Basin, Eastern Desert, Egypt: Implication of Pediastrum rhythmic signature by Tahoun et al. (2017) Marine and Petroleum Geology 88 (871–887)"

Abstract Herein, we reply to the allegations made by Anan et al. (2018) who claimed that the rhythmic signature of Pediastrum originally recorded and interpreted for the first time by (Tahoun et al., 2017), is a simulation of the work of El Atfy et al. (2017). This is not possible because we submitted our manuscript (which comes from an earlier version previously submitted to JMPG) almost simultaneously with the online publication of El Atfy et al. (2017); therefore, we had no chance to incorporate their work. Anan et al. (2018) raised such claims, because we provided scientific criticism to El Atfy et al. (2017) and did not follow their work blindly. Moreover, our work has different aims and approaches with respect to those used by El Atfy et al. (2017). Our main idea was to study and explain how the vertical cyclic signature of Pediastrum is connected to sea level cyclicity and to use this vertical stratigraphic signature in paleoenvironmental and sequence stratigraphic interpretation. This aim was not tackled before by Brenac and Richards (2001) and El Atfy et al. (2017). Moreover, our work was based on palynological, geophysical and lithologic data, not on mineralogical data as made by El Atfy et al., 2017). In our paper (Tahoun et al. (2017) we decided to discuss the work of El Atfy et al. (2017) because they tried to relate Pediastrum to regressive sequence systems. We found their work has several scientific mistakes that would raise much scientific controversy and lead to unsubstantiated conclusions. In our opinion, El Atfy et al. (2017) did not use reliable data and failed to provide proper scientific evidence to their conclusion. Following El Atfy et al. (2017), Anan et al. (2018) related an alleged acme of Pediastrum to regressive systems tracts, without providing any quantitative evidence of the acme and/or making a sequence stratigraphic analysis of their studied sections. Not surprisingly, the failure of Anan et al. (2018) to provide any quantitative data to support their alleged acme reinforces our argument that their study was not based on genuine data. Moreover, Anan et al. (2018) tried to flatten the conclusion made by Tahoun et al. (2017) by underestimating its sounding Pediastrum rhythmic signature-based results. Anan et al. (Op. cit.) also tried to bend the clear fact that our ideas differ from that of El Atfy et al. (2017) to look as it was their own, which is not true. Therefore, we encourage the palynologists community to read critically the work of Tahoun et al. (2017) and the work defended by Anan et al. (2018) and their allegations to confidently scrutinize the aims, data quality, and approaches presented therein to come up with an independent judgment. A detailed reply to allegations and comments of Anan et al. (Op. cit.) are handled in the forthcoming sections.