North Western Desert Research Articles

Basement Depth Map Estimation and Linear Features Detection Depending on Interpretation of Magnetic Data at Qarun Oil Field and Surrounding Areas, North Western Desert, Egypt

This investigation primarily targets a specific area situated in the northeastern Western Desert and northwest Beni-Suef, covering Wadi Al Rayan area, Gindi basin, Kattaniya inversion, and El-Fayum depression. It extends to the east of the river Nile. This study aims to Evaluate the depth of the basement complex in the area under investigation. The total aeromagnetic intensity data was reduced to the north pole (RTP) for clarity. 2D modeling of this RTP data was then used to evaluate the basement depth. The analysis of basement depth maps revealed significant variations in the subsurface structure of the study area, showing both elevated features (horsts) and depressed areas (grabens). The elevated basement (horsts) was found to be at a depth of approximately 813 meters, while the deepest depression (grabens) reached down to 7600 meters. Based on magnetic data combined with eight wells drilled into the basement complex, a basement lineament map of the area is delineated as a result of the investigation. This map shows a series of large alternating highs and valleys in ENE-WSW, NE-SW and E-W trending bands. Together with other minor trends, these major trends have shaped the basement surface into several tilted fault blocks, creating anticlinal and syncline zones of different depths and directions to form the Qattrani-El Gindi low trends. Whereas the high trend is located in El Fayum, El-Sagha, and Abu Rawash areas. The study helped to re-evaluate the subsurface structures affecting the Qarun oil field's hydrocarbon accumulation.

Characterization of recharge sources of the Miocene Fluvial Moghra aquifer in the North Western Desert of Egypt

Study regionThe Miocene Fluvial Moghra Aquifer in the North Western Desert of Egypt Study focusThe study integrates stable isotope analyses with aeromagnetic and hydrogeological datasets to accomplish the following: (1) define the primary source(s) of recharge to the Moghra aquifer, (2) assess aquifer connectivity with the Nile River aquifer, and (3) investigate the vertical connectivity of the Moghra aquifer with the underlying Nubian Aquifer System (NAS) through subvertical faults. New hydrological insights for the regionThe findings reveal (1) significant heterogeneity in groundwater isotopic compositions (Group A: δ18O: 1.1–13.8 ‰; δD: 4.6–73.5 ‰, B: δ18O:−0.99 to 0.85; δD: −7.58 to 4.38 ‰; and C: δ18O:−1.1 to −3.4; δD: − 6.3 to −18.2 ‰) indicative of variability in recharge sources. (2) Groundwater compositions west (up to 30 km) of the Nile River (Group A) resemble enriched modern Nile waters following the Aswan High Dam (AHD) construction that give way further west to relatively depleted groundwater (Group B) resembling historical pre-AHD Nile water compositions. (3) Further west from Group B depleted Group C samples occur along intersections of multiple fault systems (NW and NE-oriented faults) interpreted as mixtures of rising highly-depleted paleo Nubian Aquifer System (NAS) waters and pre-AHD Nile waters. (4) The advocated structural control is reported in similar settings in Egypt, suggesting that intersections of multiple fault systems provide regional connections between deep and shallow aquifers in northeast Africa, recharge overlying shallow aquifers, and should be considered in groundwater management scenarios.

The Carboniferous spore genus Vestispora: New palynological insights from Gondwana

Palynological studies from Europe and North America have repeatedly considered the Carboniferous miospore genus Vestispora a useful biostratigraphic indicator, resulting in a detailed review and discussion of its variable morphotypes. This was not the case in Gondwana, where Vestispora has rarely been reported. However, a few studies from India and South America used the absence of this taxon as an argument for a Permian age.The present work introduces a well-preserved and diverse record of five species of Vestispora from the Pennsylvanian (Moscovian-Gzhelian) of the Dhiffah Formation, north Western Desert (NWD), Egypt. Moreover, a detailed review of previous records of Vestispora was introduced in a trial to understand its regional distribution in Gondwana. It turned out that Vestispora is restricted to the Tethyan realm or the vegetation belt stretching North of Gondwana. However, the genus seems to exhibit a wider stratigraphic range in the Tethyan realm of Gondwana than in the Euramerican Province, with the youngest occurrences up to the top of the Carboniferous.

Integrated seismic, petrophysical, and geochemical studies for evaluating the petroleum system of the Upper Bahariya-Abu Roash G sequence in the Karama Field, Abu Gharadig Basin, North Western Desert, Egypt

The main aim of this study is to delineate the hydrocarbon potential and evaluate the petroleum system elements of the Cenomanian Abu Roash G (AR/G) and the Upper Bahariya Members in the Karama Field. It lies at the southeast borders of the Abu Gharadig Basin, a well-known basin in the W.D. to the NE of Africa. We accomplish this study by analyzing a total of thirty 2D seismic profiles, a complete data set of well logs for five wells, and their geochemical data. The workflow starts with illustrating the dominant subsurface structural features, defining the main potential reservoirs and their parameters, and checking the maturity of the probable source rocks. The seismic interpretation indicated that the research area had been influenced by a NE-SW anticlinal structure accompanied by a set of WNW-ESE and NW-SE normal faults that are controlled by the positive compression inversion process that dominated during the Late Cretaceous. Analyzing and processing the well log data sets suggest that the reservoirs of the Abu Roash G (AR/G) and the Upper Bahariya Members are characterized by poor to good reservoir settings with net-pay thickness reaching up to 13–50 feet in the different wells (av. Effective porosity (∅eff) = 17.7 % and 15.6% for the AR/G and the Upper Bahariya Members, av. Shale volume (Vsh) = 17.4 % and 13.6 %, av. Water saturation (Sw) = 38.9 % and 39.8 %, while av. Hydrocarbon saturation values (So) = 60.2 % and 61.1%, respectively). The geochemical and maturity analyses assisted in determining the potential mature source rocks of the Jurassic Khatatba Shale (TOC = 0.70–5.67%; S1+S2 = 0.43–5.97 mg/g, Ro = 0.54–1.06 %) with some contribution from the Cretaceous sources (Alam El-Bueib and Bahariya Formations). Studying elements of the petroleum regime of the Karama Field indicates that the trapped hydrocarbons are structurally controlled by three-way dip closures, horst blocks, sealing faults, and vertical sealing by impervious shale and limestone beds. This case study could be applied to similar analogs in other oil fields in the Egyptian Western Desert to delineate their hydrocarbon potential and structural setting.

Formation Evaluation and Petrophysical Analysis of Well Logging Data: an Example From Matruh-Shushan Basin, North Western Desert, Egypt

Petrophysical evaluation of well logging data is crucial for exploring and improving oil and gas reservoirs. This involves obtaining reliable information about the rocks and fluids in the reservoir to estimate reserves and make informed decisions about drilling, production, and development strategies. In this study, data from six wells in the Matruh-Shushan Basin were evaluated using Log Quality Control procedures. Two zones of interest, Lower and Upper Safa members, were identified, and quantitative interpretation was conducted to determine the most effective parameters defining reservoir quality: Shale Volume, Effective Porosity, and Water Saturation. Results were positive, with promising net pay for both reservoirs. Numerical models and statistical methods were used to account for data uncertainties and provide reliable estimates of reservoir properties. The study highlights the significance of correct interpretation in successfully exploring and producing hydrocarbons.

Linking petrophysical heterogeneity and reservoir rock-typing of the post-rift shallow marine siliciclastics to their depositional setting: The Upper Cretaceous Bahariya reservoirs, north Western Desert, Egypt

The upper Cretaceous clastic facies of the Bahariya Formation host the main reservoir intervals in the north Western Desert (NWD) of Egypt. These clastics were deposited in a parallic depositional environment characterized by different scales of reservoir heterogeneities. However, the link between these heterogeneities and the depositional setting of the reservoir facies is still blurred. In this study, we investigate a highly-heterogeneous reservoir facies of Bahariya Formation in Yasser Field wells, NWD in order to construct a predictive framework for the distribution of the best reservoir rock types (RRTs) and flow zones. Seismic stratigraphy was integrated with core sedimentology to understand the depositional architecture of the reservoir facies. Moreover, conventional core analysis and wireline logs were interpreted to evaluate the scales of lithological and petrophysical heterogeneities in the different RRTs.In the studied Yasser Field, the Bahariya Formation consists of tidal facies deposited in a wide range of tidally-influenced conditions. The seismic facies varies greatly with variation in the tidal regime. Best reservoir rock types RRTs are associated with tidal channels and amalgamated tidal bars (RRTI). RRTI rocks represent the main fluid flow conduits in the studied Bahariya reservoir. Lithological and petrophysical heterogeneities are more prominent in the tidal mud flat and mixed tidal flat facies which form RRTIII rocks. Linking seismic with sedimentary facies enabled us to predict the distribution of the best reservoir flow zones in the study region. The present results establish a framework for predicting the optimum reservoir quality facies based on integrating seismic, sedimentary and petrofacies. This framework could be applied in analogous tidally-influenced reservoir facies with high depositionally-controlled pore system heterogeneity.

An iterative workflow introduced to model complex heterogeneous reservoirs: an example from NEAG-2 Field, north Western Desert, Egypt

An iterative workflow introduced to model complex heterogeneous reservoirs: an example from NEAG-2 Field, north Western Desert, Egypt

Ethane integration project—a study for Egyptian NGLs plants and their economics

For Egypt, ethane is a vital chemical precursor, with the potential to significantly attract financial resources and drive economic growth. Enhancing its added value necessitates efficient recovery of ethane before it enters the national grid without processing. This research investigates the technical and economic feasibility of integrating natural gas liquids (NGLs) from three Egyptian NGLs plants—South Western Desert NGLs (SWD NGLs), North Western Desert NGLs (NWD NGLs), and East Mediterranean NGLs (EMD NGLs)—to improve ethane recovery from natural gas fields. The study focuses on revamping these NGLs plants using various NGLs recovery techniques, conducting a comprehensive comparison to identify the most effective methods for processing rich feed gas. Detailed design of the NGLs recovery processes was developed using HYSYS V.14 simulation software and supplementary calculation sheets. The design criteria encompass both technical and economic parameters to ensure a holistic approach in meeting project requirements. Results indicate a significant increase in ethane recovery: 16% for SWD NGLs, 10% for NWD NGLs (A, B, C), and 85% for EMD NGLs. This improvement will boost ethane feedstock for petrochemical companies from 2000 ton/day to 3500 ton/day, enabling increased polyethylene production. Economic analysis for the base case shows an expected internal rate of return (IRR) of 26%, a net present value (NPV) of USD 73 million, and a payback period of approximately 3 years. Sensitivity analysis on product prices, feed gas prices, and total capital investment confirms the project’s economic viability, with all cases showing feasibility (IRR ≥ 15%) except when product prices fall below USD 225/ton for propane, USD 215/ton for liquefied petroleum gas (LPG), and USD 25/bbl for condensate. This study highlights the potential for enhanced ethane recovery, offering substantial economic benefits and supporting the growth of Egypt’s petrochemical industry.

Hydrocarbon Potentialities of Carbonate Rocks for Abu Roash/D Member (AR/D): Petrosannan Field, Abu Sannan Area North Western Desert, Egypt

Hydrocarbon Potentialities of Carbonate Rocks for Abu Roash/D Member (AR/D): Petrosannan Field, Abu Sannan Area North Western Desert, Egypt

Formation evaluation and seismic interpretation of the Jurassic sedimentary section in the Matruh concession, North Western Desert, Egypt

Formation evaluation and seismic interpretation of the Jurassic sedimentary section in the Matruh concession, North Western Desert, Egypt

Assessment of Middle Jurassic sedimentary sequence’s petroleum system at Imhotep-W-1X well, Northwestern desert, using integrated geochemical, geomechanics, XRD, and basin modeling

Assessment of Middle Jurassic sedimentary sequence’s petroleum system at Imhotep-W-1X well, Northwestern desert, using integrated geochemical, geomechanics, XRD, and basin modeling

Petrophysical and petrographical delineation for carbonate reservoir rocks in north Western Desert, Egypt

Petrophysical and petrographical delineation for carbonate reservoir rocks in north Western Desert, Egypt

Petrophysical evaluation of Lower Bahariya Reservoir using integrated ‎well-logs and core data analysis in Yasser field, North Western Desert, ‎Egypt.‎

Petrophysical evaluation of Lower Bahariya Reservoir using integrated ‎well-logs and core data analysis in Yasser field, North Western Desert, ‎Egypt.‎

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.

Climate variability in northern Africa during the late Holocene: A multiproxy perspective from El-Beida Lake (Wadi El-Natrun, Egypt)

North Africa is a key region hosting ca. 230 million people that are dependent on climate to maintain their subsistence through agriculture. Because of the current global changes, understanding the mechanisms behind the climate variations that occurred in this region is extremely important. To contribute to a more accurate modelling projection, we reconstructed the paleoclimatic and paleoenvironmental variations from the Meghalayan (∼1,500 ka) to recent using palynological and geochemical data from a sediment core from El-Beida Lake (Wadi El-Natrun area, north Western Desert of Egypt). North Africa underwent significant shifts in climatic conditions forced by different drivers since the Roman Warm Period (RWP) until recent. Our sediment core record indicates that this region experienced a persistent dry and warm climate during the RWP until the first half of the Medieval Climate Anomaly (MCA). The positive North Atlantic Oscillation was the main driver for controlling the precipitation pattern and pushing the precipitation towards central and north Europe and favoring the dry climate in North Africa during the RWP. The dry and slightly cold conditions in the study area during the Dark Age Cold Period (DACP) can be ascribed to the coupling between the more southward position of the Azores Front and the weak Atlantic Meridional Overturning Circulation. Northern Africa showed variable climatic conditions during the Medieval Climate Anomaly (MCA) due to the complicated thermohaline circulation of the Mediterranean Sea. During this time, the Eastern Mediterranean experienced a cold or partially cold MCA that may be extended to the present study area. An abrupt change to humid and cold climatic conditions occurred in northern Africa during the Little Ice Age (LIA) due to large-scale processes like the ENSO and NAO. The SST warming of the North Tropical Atlantic (NTA), significantly influenced by ENSO, causes the position of the Atlantic ITCZ to be shifted northward affecting precipitation in Africa.

Assessment of the hydrocarbon potential in the black shales of the Jurassic Khatatba Formation and generated hydrocarbons, North Western Desert, Egypt: Depositional mechanism of organic rich rocks related to syn-rift differential subsidence

Jurassic rocks comprise the main source rocks in the Western Desert of Egypt. In this study, a rare case of Jurassic oil shale occurrence is recorded and studied as an extension of the Khatatba Formation. The study is based on an integrated model for oil shale deposition using seismic data, organic geochemical analyses, and palynomorph thermal alteration assessment to determine the hydrocarbon generation potential of these rocks. The seismic data were used to construct structure and lithofacies models and to relate the facies distribution with the geochemical parameters of the different rock units in addition to examining the lithofacies changes between the study wells adding value to the understanding of the environment of deposition and the structure of the study area. The Zahra, U. Safa, and L. Safa members are affected by two sets of normal faults, the first of which has a downthrown side to the east while the second set has downthrown westward sides. The 3D facies models show that the Zahra Member is composed mainly of limestone encountered in the central parts of the basin, while shale is mostly found in the north. The U. Safa consists mainly of sandstone and the L. Safa consists of sandstone and siltstone. The geochemical evaluation shows organic richness ranging from poor to good for the Zahra, while the Safa shows poor to excellent richness. Kerogen is Type III and IV in most samples. The Zahra samples are immature in the TUT-21X well and mature in only one sample from the AMOUN NE-2X well. The U. Safa samples are immature to marginally mature while the L. Safa samples are marginally mature to mature in the TUT-21X well and immature in the SHAMS-15X well. Palynomorph thermal alteration data confirm the above maturation levels. The bulk and biomarker composition of two oils samples from U. and L. Safa, AMOUN NE-1X well, are similar and indicate a terrigenous source of the kerogen. The oils are not biodegraded but are normal mature oils generated by kerogen that was deposited under oxic conditions. Data integration from this study can be used to show the variation in organic richness (TOC) and thermal maturity (Tmax) in the area between the four wells, which will help define the exploration risk and provide for a new vision for more exploration activity.

Hydrogeophysical investigation at El-Hammam area, North Western Desert, Egypt

Hydrogeophysical investigation at El-Hammam area, North Western Desert, Egypt

Rainfall partitioning characteristics by two sand‐binding shrubs and their impact on shallow soil moisture replenishment in the Northwestern desert steppe of China

AbstractRainfall partitioning by the vegetation canopy into stemflow (SF) and throughfall (TF) plays a crucial role in soil infiltration and the local water balance. This study aims to quantify the differences in SF and TF between two sand‐binding shrubs, Caragana liouana and Salix psammophila, in the desert steppe, clarify the effects of biotic and abiotic factors on them using the boosted regression trees (BRT) model, and compare soil moisture replenishment during the growing seasons of 2021 and 2022. Under identical rainfall conditions, the canopies of C. liouana and S. psammophila can lead to differences in rainfall partitioning. The SF percentage ranged from 0 to 23.70% for C. liouana and from 0% to 3.3% for S. psammophila, respectively, while the TF percentage ranged from 42.12% to 90.07% for C. liouana and from 52.39% to 94.87% for S. psammophila. The funnelling ratio for C. liouana (69.59) is 1.19 times higher than for S. psammophila (58.36). Rainfall amount is the primary variable affecting rainfall partitioning. The average soil moisture replenishment and soil moisture conversion efficiency under the C. liouana canopy are 11.02 mm and 58.39%, respectively, which are significantly higher than those for S. psammophila (4.84 mm and 24.33%, respectively). These findings suggest that C. liouana, with its relatively higher SF and soil moisture conversion capability compared to S. psammophila, plays a significant ecohydrological role in water‐limited ecosystems. This study provides a reference for species selection and ecological management in vegetation restoration efforts in desert steppes and similar regions.

Biomarker characteristics of organic shale beds of Alam El Bueib Formation in Tut Oil Field, Shushan Basin, North western Desert, Egypt: Insights from oil/source rock correlation

Biomarker characteristics of organic shale beds of Alam El Bueib Formation in Tut Oil Field, Shushan Basin, North western Desert, Egypt: Insights from oil/source rock correlation

Subsurface Structure Delineation Using Gravity and Magnetic Data Interpretation at the Area South Gebel Miswag, Northwestern Desert, Egypt.

Subsurface Structure Delineation Using Gravity and Magnetic Data Interpretation at the Area South Gebel Miswag, Northwestern Desert, Egypt.