A Study of Microfacies and Petrophysical Analysis of Some Subsurface Cretaceous Rocks of Abu Gharadig-34 Well,Western Desert,Egypt

Abstract

The main aim of this study is to shed light on the microfacies association, petrophysical parameters, and depositional environment of different rocks such as sandstone, limestone, shale, siltstone, and dolomite of subsurface Cretaceous rock units (Abu Roash “C” member, Abu Roash “E” Member, and Bahariya Formation) from Abu Gharadig-34 well in the north western desert, Egypt. In this study, nine microfacies were identified. These microfacies include calcareous siltstone, bioclastic wackstone, ferruginous sublithic arenite, dolomitic lithic arenite, lithic arenite, fossiliferous bioclastic wackstone, glauconitic dolomitic sublithic arenite, ferroan dolomite, and ferruginous sandy siltstone. Generally, subsurface Cretaceous rock units are deposited in different depositional environments ranging from tidal flats to open circulation passes through restricted circulation shelves. Statistical analysis of the petrophysical data showed that the highest porosity was concentrated at Abu Roash “C” member, which had very good porosity and high permeability. The porosity increased when the bulk density decreased. The permeability of the studied samples was the same as the porosity, which increased when the bulk density decreased. It can be concluded that Abu Roash “C” member is a good reservoir in the Abu Gharadig-34 well.     

CRETACEOUS SOURCE ROCKS AT THE ABU GHARADIG OIL- AND GASFIELD, NORTHERN WESTERN DESERT, EGYPT

The Abu Gharadig oil- and gasfield is located in the north of the Western Desert of Egypt. In this paper, the geochemical characteristics of kerogens from Cretaceous shales at this field are described. The shale samples came from the Abu Roash Formation E and G Members (late Cenomanian- Turonian), the Bahariya Formation (early Cenomanian) and the Betty Formation (Neocomian- Barremian). Kerogen type and quality was evaluated by optical microscopy and by standard methods (elemental analysis, infrared spectroscopy and Rock-Eval pyrolysis). The results show that the shale samples analysed contain fair to high quantities of organic matter, and that this takes the form of marine amorphous sapropelic and structured liptinite macerals which can be classified as Types I and II kerogens.
Maturation indicators and burial history curves indicate that shales from the Abu Roash E and G Members are currently located in the oil-generation window. Oil generation in these units has taken place since the late Palaeocene-early Eocene—i.e. since the formation of structural traps in the Abu Gharadig area, which occurred in the Maastrichtian—Eocene. Shales in the Bahariya and Betty Formations passed through the oil window during the Late Cretaceous before the traps were formed, but the shales reached the wet-gas zone in the late Miocene - early Pliocene.
Most of the liquid hydrocarbons in the Abu Gharadig field are sourced by Cretaceous shales in the Abu Roash E and G Members; and most gas is generated by shales in the underlying Bahariya and Betty Formations. The Jurassic Khatatba Formation may also have generated some gas.     

The impact of seismic interpretation on the hydrocarbon trapping at Falak field,Meleiha, Western Desert,Egypt

The object from this study is to find ways to develop field and discover the possible reservoirs and appropriate solutions to avoid the problems we have faced before in the drilled wells that led to drilling dry wells close to producing wells. A set of twenty reflection sections have been used to highlight the subsurface structural setting and the hydrocarbons entrapment styles in Falak field in the northern Western Desert, this is achieved through an integrated geological and geophysical studies utilizing a number of maps and cross sections, all of that for demonstrating all the chances for exploring or developing the field. The reflectors are Ras-Qattara formation, Khatatba-2D member, Masajid formation, Alam El Beuib 3G member, AEB 3F member, AEB 3E member, AEB 3D member, AEB 2A member, AEB 1 member, Alamein Dolomite formation, Dahab Shale member, Kharita formation, Bahariya 5 member, Bahariya 4 member, Bahariya 1 member, Abu Roash “G” member, Abu Roash “E” member, Abu Roash “A” member, and the Apollonia formation. The N-S and E-W trending seismic sections revealed normal faults forming shape seems to be horsts all over the mapped field, these faults led to thin Cretaceous section in the up thrown block area compared to thick section on the downthrown block of the two main faults, for some instances dry hole conditions occur due to missing of structural closure on both the up thrown block and the downthrown. The TWT maps on the top of the traced reflectors reveal different structural closures with set of normal faults constructing three way dip closure in most of these faults and big shape like horst.     

Two-and-a-Half Dimension Gravity Modeling to Delineate the Structures of the Western Abu Gharadig Basin,Western Desert,Egypt

abstract

The present study is a trial to carry out 2½-dimensional gravity modeling to confirm the structures and tectonics of the western Abu Gharadig Basin, Western Desert, Egypt. This is achieved by a sequence of procedures, started by establishing the trends of six 2½-dimensional residual gravity models, most of them passing through the available control wells. Two-and-a-half-dimensional gravity modeling of mass distributions in the subsurface of the study area was performed on the significant residual anomalies of the area, which had been separated from the unwanted regional field. They were separated using the average power spectrum method available in the suite of programs provided by Geosoft (1994). Such 2½-dimensional models were constructed to reveal the dissecting structures and to subdivide the sedimentary sequence of the area into 10 time-rock and rock units (Paleozoic and Jurassic sequences, Alamein-Shaltut, Kharita, Bahariya, Abu Roash, Khoman, Apollonia, and Dabaa), in addition to the underlying basement complex. Some seismic sections were used to help constrain the construction of 2½-dimensional models.

Two-and-a-half-dimensional gravity models were constructed after transferring the structural and geologic information (fault elements and depth values) of the two-dimensional gravity models to the base maps. In this way, 10 structural contour maps were established on the tops of the respective stratigraphic units. Generally, these maps reflect the considerable effect of the NE-SW and NW-SE trends as major directions of fracturing in the study area of the northern Western Desert of Egypt.     

Source rock evaluation of some upper and lower Cretaceous sequences,West Beni Suef Concession,Western Desert,Egypt

West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history and calculate the levels of thermal maturity of the Fayoum-1X well based on calibration of measured %Ro and T_max against calculated %Ro model. The calculated Total Organic Carbon (TOC) content from well log data compared with the measured TOC from the Rock-Eval pyrolysis in Fayoum-1X well is shown to match against the shale source rock but gives high values against the limestone source rock. For that, a new model is derived from well log data to calculate accurately the TOC content against the limestone source rock in the study area. The organic matter existing in Abu Roash (F member) is fair to excellent and capable of generating a significant amount of hydrocarbons (oil prone) produced from (mixed type I/II) kerogen. The generation potential of kerogen in Abu Roash (E and G members) and Betty formations is ranging from poor to fair, and generating hydrocarbons of oil and gas prone (mixed type II/III) kerogen. Eventually, kerogen (type III) of Kharita Formation has poor to very good generation potential and mainly produces gas. Thermal maturation of the measured %Ro, calculated %Ro model, T_max and Production index (PI) indicates that Abu Roash (F member) exciting in the onset of oil generation, whereas Abu Roash (E and G members), Kharita and Betty formations entered the peak of oil generation.     

Origin of Bahariya oil in Salam oil field,Western Desert- Egypt

The origin of Bahariya oil is a debatable issue. Bahariya Formation produces oil from the Lower sandstone unit by normal pressure mechanism, while the Upper Bahariya shale produces oil by fracking mechanism. The main question is: is there any genetic relationship between the two oils.To answer this question, “50” ditch samples, “12” extract samples and “2” oil samples represent Khatatba and Bahariya formations and Abu Roash ‘G’ Member, collected from six wells drilled in Salam oil field, have been geochemicaly analyzed, using LECO SC632, Rock–Eval- 6 pyrolysis, GC and GC/MS techniques.The analysis shows that the Total Organic Carbon content (TOC) for the studied formations ranges from fair to v.good, with poor to good hydrocarbon potentiality. The maturity evaluation using Tmax, and calculated Vitrinite reflectance (R_o) showed that the studied samples have good thermal maturation reaching the stage of oil generation. Also the analysis revealed that the kerogen is a mixture of type II/III kerogen, reflecting the potential generation of oil and gas. The GC and GC/MS data showed that the organic matter is a mixed marine/terrestrial input deposited in transitional environment under prevailing reducing conditions. The oil samples fingerprint of the saturated hydrocarbons fraction from Baharyia reservoir (Lower and Upper) members suggest that the oil samples have a mixed organic source with significant terrestrial organic matter input deposited under saline to hypersaline environment with slightly oxidizing environment.Based on the obtained results, it is suggested that the Bahariya oil has been sourced mainly from deeper horizons (Khatatba Formation) with some contribution from upper and lower Bahariya source rocks.     

GEOCHEMICAL CHARACTERIZATION OF POTENTIAL JURASSIC/CRETACEOUS SOURCE ROCKS IN THE SHUSHAN BASIN, NORTHERN WESTERN DESERT, EGYPT

Some 180 core and cuttings samples of shales and limestones from the Middle Jurassic – Late Cretaceous succession (Khatatba, Masajid, Alam El-Bueib, Alamein, Kharita, Bahariya and Abu Roash Formations) were collected from wells Ja 27–2, Tarek-1 and Jb 26–1 in the central, structurally-low part of the Shushan Basin and from well Lotus-1 in the structurally-elevated western part of the basin. All samples were screened for total organic carbon (TOC) content. Selected samples were then analyzed by Rock-Eval pyrolysis, and extracted for biomarker analyses. Visual kerogen analysis and vitrinite reflectance measurements were also undertaken and oil - source rock correlations were attempted. The results indicate that the thermal maturity of the samples can be correlated closely with burial depth. Samples from the central part of the basin are more mature than those from the west. Samples from the central part of the basin (except those from the Albian Kharita Formation) have reached thermal maturities sufficient to generate and expel crude oils. Extracts from the Middle Jurasic Khatatba and Early Cretaceous Alam El-Bueib Formations can be correlated with a crude oil sample from well Ja 27–2.
In well Lotus-1 in the west of the basin, four distinct organic facies can be recognized in the Jurassic-Cretaceous interval. One of the facies ("facies 4") has a sufficiently high TOC content to act as a source rock. Thermal maturities range from immature to peak oil generation, and the top of the oil window occurs at approximately 8000 ft.     

Geochemistry,generation and maturation of the hydrocarbons at Wadi Al-Rayan oil field,Western Desert of Egypt

`The present work aims to study the organic chemistry, the generation and maturation of the hydrocarbons encountered at Abu Roash Formation, Wadi El Rayan oil field. The analysis of source rocks indicates the presence of two organic facies. The first is characterized by high total organic carbon of 0.93–3.39%, strongly oil-prone (Type II), and good potential for oil generation (pyrolysis S2 yields 4.54–23.26 mg HC/g rock and HI 488–705 mg HC/g TOC). The second attains good range of organic carbon from 0.90% to 1.57%, which is a mixed oil and gas (Type II–Type III) of fair hydrocarbon generation (pyrolysis S2 yield of 1.98–5.33 mg HC/g). The kerogen type consists of unstructured lipids and some terrestrial material. Plot of Pr/n-C17 versus Ph/n-C18 indicates that the crude oil was derived from mixed source rock, while the maturity profile assigns oil windows (0.6 R_o%) matching topmost of Abu Roash G Member.     

Evaluation of possible source rocks and extracts characteristics from Safir-1x well,North Western Desert,Egypt

The pyrolysis and vitrinite reflectance estimations for fifteen shale rock tests and additionally, geochemical burial history, and gas chromatography – mass spectrometry parameters were talked about to explore the hydrocarbon generation and maturation level and time, type of hydrocarbon produced of rock units of Safir-1x well. The results assign that the Bahariya Formation is poor to great source rock to create oil and gas, with a lower thermal maturation degree than the Khatatba and Alam El Bueib formation. Alam El Bueib is viewed as good to excellent source rock for oil and gas age, having marginally high level of thermal maturation at oil window at around 40 million years. Khatatba formation achieved the oil and gas generation window at about 80 and 50 million years separately and considered excellent source rock.

The molecular gas chromatography and mass spectrometry parameters demonstrated that the extracts of source rocks reflected that the Bahariya and Alam El Bueib extracts have a mixed sources formed under transitional conditions at low grad of thermal maturation. Khatatba source rock extracts originated from marine sources formed under reducing conditions at high grade of maturation.     

Source rock evaluation of Kharita and Bahariya formations in some wells,North Western Desert,Egypt: Visual palynofacies and organic geochemical approaches

Palynofacies analyses were applied on ninety-one samples from the subsurface Albian – Cenomanian succession represented by Kharita and Bahariya formations, encountered in El-Noor, and South Sallum wells, located in the North Western Desert, Egypt, to visually characterize the content of dispersed organic matter, as well as, organic geochemical characterization to reveal the depositional paleoenvironments and source rock potentiality. The result recognized of five palynofacies associations in the studied interval. The deposition of Kharita Formation took place mainly in a steady and a relatively stable deltaic to marginal environment continued as well in the lower part of Bahariya Formation with minor changes. The marine influence became more common in the upper part of Bahariya Formation showing the exceptional high hydrocarbon potential recorded in the studied interval. This indicates marine transgression by the end of the early Cenomanian (Upper Bahariya) age. Samples from the Kharita Formation contain abundant brown phytoclasts which suggest gas-prone kerogen type III and IV. While Bahariya Formation includes translucent, brown cuticles and woody tracheid phytoclasts pointing to more promising gas-prone kerogen type III. The organic geochemical analysis shows poor to fair gas-prone source rock potential within the study section., Thermally, the color of the spore grains in Kharita and Bahariya formations show that dark yellow to orange, indicates immature besides their general little poor hydrocarbon generation potentiality.     

Petrographic and petrophysical characterization of some Paleozoic rocks,Um Bogma area,Southwest Sinai,Egypt

Sixty-two samples were collected from the five formations at Um Bogma area, (Southwest Sinai, Egypt). Nine samples were collected from Sarabit El Khedim Formation, ten samples were collected from Abu Hamata Formation, eighteen samples were collected from Adedia Formation, eight samples were collected from Um Bogma Formation and eighteen samples were collected from Abu Thora Formation.The Paleozoic rocks at Um Bogma area, consist mainly of sandstones, siltstones, shales, limestone and dolostones, which are unconformably overlie igneous and metamorphic rocks (granite, diorite and gneiss) of Precambrian age.The petrographic studies were applied to identify different rock units, different facies and its diagenetic history and to reveal its effect on the storage capacity properties. Different types of porosity (oversized, intergranular, fracture and vuggy porosities) have been identified based on the petrographic investigation of the studied thin sections.The Paleozoic sandstone rock samples are characterized by porosity average about 19% for Facies 1 (quartz wack) and about 18%for Facies 2 (quartz arenite) and permeability average 420?mD for Facies 1 (quartz wack) and 690?mD for Facies 2 (quartz arenite), so these rocks can be considered as good reservoir rocks. The Paleozoic carbonate rock samples (Facies 3) are characterized by poor porosity (less than 7%) and very low permeability (less than 0.5?mD), which caused by matrix and diagenetic processes and refer to bad reservoir rocks.Porosity can be linked to the two derived electrical properties (formation resistivity factor and electrical tortuosity) of the studied Paleozoic rocks at Um Bogma area. The electrical tortuosity has significant effects on both permeability and formation resistivity factor. The permeability decreases with increasing electrical tortuosity and the relation between both of them is inverse relationship with good coefficient of correlation. The permeability decreases with increasing electrical tortuosity and the relations between both of them are inverse relationships with high coefficient of correlation. The formation resistivity factor increases with increasing electrical tortuosity and the relations between both of them are positive relationships with a fair to very high coefficient of correlation.     

The Petrography,Mineralogy, and Hydrocarbon Potential of the Shales of the Duwi Formation,Abu Tartur,South Western Desert,Egypt

Abstract

Eight shale samples related to the Duwi Formation (Campanian-Maastrichtian) of the Abu Tartur mines of the southwestern desert of Egypt were petrographically, mineralogically, and geochemically studied. The study results indicate that the detrital material of these shales were derived mainly from mafic to ultramafic components of the basement rocks under intensive chemical weathering and deposited in an alkaline reducing marine environment of low energy and these shales do not attain the requirements of hydrocarbon production.     

3D seismic and formation micro-imager (FMI) integrated study to delineate depositional pattern of Abu Madi (Upper Miocene) clastic reservoir rocks in El-Wastani gas field,onshore Nile Delta,Egypt

Ten wells (EW-4, EW-5, EW-6, EW-7, EW-8, EW-9, EW-10, EW-12, EW-13 and EW-15) were interpreted using the composite well logs, data of core analysis, gamma-ray logs, formation micro-imager logs (FMI), and 3D seismic data in SEGY format to understand the stratigraphy of the onshore, Nile Delta, Egypt.The amplitude analysis of 3-D seismic horizon slice of Lower Abu Madi rock unit together with the lithostratigraphic correlation through the study area depending on the gamma-ray log “HSGR” (left to right increasing), and the identification of type of bed geometry, nature of bed contacts, type of the sedimentary structures and the dominant formative paleocurrents by using some available borehole micro-resistivity images (FMI) and core photos. All of these techniques are used together to define the different depositional facies and depositional environment of the Messinian clastics (Lower Abu Madi rock unit), which is considered to be the main reservoir in the El-Wastani gas field, onshore Nile Delta, Egypt.The present study of depositional pattern of the Upper Miocene clastics reservoir (Lower Abu Madi rock unit) revealed that it is represented by high sinuous meandering channels or paleo-valley and three types of fluvial facies were defined; channel fill, channel margin, and floodplain basin.     

埃及西沙漠盆地中生界烃源岩特征及剩余资源分布

西沙漠盆地是埃及三大主要含油气区之一,已发现大量的油气田,现处勘探发现中期,预探风险增大。为此,在详细评价盆地烃源岩地球化学特征基础上,运用盆地数值模拟技术定量分析剩余资源潜力。研究认为,中侏罗统Khatatba组Safa段和Zahra段煤系暗色泥页岩以及上白垩统Abu Roash组AR-F段暗色泥页岩是盆地的3套主力烃源岩,各凹陷烃源岩广泛分布,厚度变化较大。Khatatba组烃源岩TOC含量在0.5%~10%,裂解烃S₂含量高,为中等-很好烃源岩;Abu Roash组AR-F段烃源岩TOC主要在0.5%~3%,裂解烃S₂含量中-高,属中等-好烃源岩。这3套烃源岩有机质干酪根类型以混合Ⅱ型为主,其次是Ⅲ型,少量为Ⅰ型。指出Khatatba组2套烃源岩全盆处于热演化成熟大量生排烃阶段,凹陷中心达高熟生烃、局部过熟生气阶段,油气并生;Abu Roash组AR-F段烃源岩仅Abu Gharadig和Natrun凹陷进入成熟生烃阶段。提出盆地北部地区主要由侏罗系Khatatba组烃源岩供给油气,东南部地区则有侏罗系Khatatba组和白垩系AR-F段双源供烃。计算表明,盆地剩余可采资源量达6.51×10⁸ t,剩余资源潜力很好;其中,南部Abu Gharadig凹陷古生界、侏罗系和下白垩统AEB,北部Matruh凹陷古生界、Faghur凹陷上白垩统,油气探明程度低,剩余资源可观,为下步勘探的有利方向。     

Sedimentary facies analysis of the Upper Bahariya sandstone reservoir in East Bahariya C area,North Western Desert,Egypt

The present work aims to deduce the depositional processes of the Lower Cenomanian Bahariya Formation, that is one of the main hydrocarbon siliciclastic reservoirs in the Northern Western Desert of Egypt. This has been achieved through the analyses of the core photographs, micro-resistivity image logs, mud logs and conventional wireline logs. The Bahariya Formation comprises a complex of depositional lithofacies such as interbedded siltstone, shale, sandstones and pebbly sandstones. The current work highlights the effectiveness of the integrative approach. A variety of datasets including core photographs, micro-resistivity image logs, mud logs and conventional wireline logs are integrated to define the conceptual depositional model in the study area.Different recorded sedimentary features point to various depositional processes. Hummocky cross stratification (HCS) is the common sedimentary structure indicating the storm action. Wave ripples are recorded providing evidence for fair-weather action on shoreface. Rhythmic heterolithics, tidalites indicate the tidal processes. The upper part of the Bahariya Formation has been influenced by wave and storm processes more than the lower parts. The core and image facies are designated, being dominated by Sandstone (S), Siltstone (Z), Mudstone (M), Heterolithic (H) and Limestone (L.s). The studied core and image facies with wireline logs facies are grouped into five major facies associations (FA). They are Tidal Channel and Tidal Creeks, Tidal Flat, Storm, Shoreface, Offshore Transition to Offshore Facies Associations. The integrative approach indicates that the Upper Bahariya Member has been deposited in a storm influenced tidal coastal realm.     

An Experimental Study of the Effect of the Water Injection Process on Rock Structure and Permeability Reduction

Abstract

The estimation and assessment of formation damage on reservoir core samples is an important measurement. Laboratory tests were set up to investigate the effects of injection pressure, flow rate, and induced fracture on the rock sample with respect to formation damage. In this research, selected rock samples from one of Iranian giant oil fields were used as the laboratory physical model. Permeability reduction was observed for unfractured samples: however, it was more interesting that no injection pressure buildup was detected in fractured samples. It appears that fractures in sandstones, especially with weak cementation, can play the role of an agent for particle movement and cause damage far from injection wells over a long period of time.     

Petrographical,Mineralogical, and Geochemical Studies on Core-samples From Sidi Salim-1 Well,Nile Delta,Egypt

Abstract

Core samples of sandstone and clay raised from the Neogene succession of Sidi Salim-1 well were petrographically, mineralogically, and geochemically studied with the objective of determining the depositional conditions.

The sandstone is composed of quartz, feldspars of which the deeper sands of Qawasim Formation show some alteration; with rock fragments of volcanic, metamorphic, and sedimentary origin, in addition to altered biotite. These components are embedded in amorphous pyrite, microcrystalline calcite, and primary dolomite, as well as partial cementation by gypsum (mainly in the Pliocene sands).

The clays are composed primarily of montmorillonite, kaolinite, and illite. These clays were provided from mafic igneous rocks, sedimentary rocks, and intermediate igneous rocks, and were deposited under reducing conditions in a brackish lagoon intermittently receiving varying amounts of fresh water.     

ORGANIC FACIES OF EARLY CRETACEOUS SYNRIFT LACUSTRINE SOURCE ROCKS FROM THE MUGLAD BASIN, SUDAN

Cuttings samples from eight wells in the Muglad Basin have been analysed using a combination of organic geochemistry and palynofacies. The lacustrine Aptian-Albian shales of the Abu Gabra Formation, previously identified as the main source rock, have an overall mean TOC of 1.43% (n = 146), with those from the NW part of the basin (Sharaf area) being approximately twice as organic-rich as those from the SE (Heglig area). The Abu Gabra Formation contains two distinct organic facies: a lower interval dominated by higher TOC values (1.5–2.3%), higher measured hydrogen indices (338–546), higher amorphous kerogen contents (>80%), and heavier δ¹³C_TOC values (> −27%₀); and an upper, less rich interval (mean TOC 1.4%, mean HI 83, δ¹³C_TOC approximately −28%₀). The isotopic contrast between the upper and lower units may potentially be of stratigraphic use. The organic facies differences appear to reflect deteriorating preservation of the organic matter (higher dissolved oxygen, possibly due to shallower conditions resulting from lower rates of subsidence). Use of S2 v. TOC plots suggests corrected true mean hydrogen indices of around 800 in the richer facies (corresponding to a Type I kerogen). Mean random vitrinite reflectance, pyrolysis Tmax values, and visually determined fluorescence colours indicate that the samples studied are mostly immature, or at most in the earliest part of the oil window (<0.7% VR_o); biomarker data suggest that the vitrinite reflectance values may be suppressed by up to 20%.     

PETROPHYSICAL CHARACTERISTICS OF THE MESSINIAN ABU MADI FORMATION IN THE BALTIM EAST AND NORTH FIELDS,OFFSHORE NILE DELTA,EGYPT

Baltim East and North fields in the offshore Nile Delta produce gas‐condensate from accumulations located in the northern portion of the Abu Madi palaeovalley. The hydrocarbons in the Abu Madi Formation are present in sandstone reservoir units referred to as the Level III Main and Level III Lower. In this paper, the petrophysical characteristics of these reservoir units in the Baltim area are described using data from wireline logs (gamma‐ray, density, neutron, sonic and resistivity) from fourteen wells and core data from one well. Results of wireline log and core analyses indicate that the Level III Main can subdivided into two sandstone‐dominated intervals (both interpreted as sandbar deposits) separated by a shale‐rich interval which is a partial barrier to fluid flow. Effective porosity is 9–18.5% and permeability 40–100 mD. Sandstones in the Level III Lower are interpreted as braided channel facies and have effective porosity of 12.5–22% and permeability of 100–500 mD. Isoparametric maps for the Abu Madi Formation sandstone reservoirs based on log and core interpretations show the influence of depositional facies on petrophysical characteristics and can be used to assess possible targets for future exploration and development.