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In contrast to the Cenomanian-Turonian, the Coniacian-Santonian macroinvertebrates of the Middle East and North Africa are rarely investigated. Previous investigations indicated the occurrence of low diversity faunal associations, which can be attributed either to ecological (primary/biogenic) or taphonomic (secondary/sedimentologic) factors. The poorly preserved macrofauna of the Hawashia Formation (north Eastern Desert, Egypt) has been quantitively analyzed resulting in the identification of fifteen macrofaunal species including five bivalve, seven gastropod, two ammonite taxa, and one echinoid taxon. The occurrence of the ammonites Metatissotia fourneli Bayle and Texanites (T.) texanus Roemer confirm the Coniacian‒Santonian age for the Hawashia Formation. Based on litho- and biofacies, this fauna likely lived in a normal oxygen tidal-influenced shallow subtidal environment under arid conditions. Taphofacies indicates a low-energy regime with low sedimentation rate. Most shells are highly damaged (encrusted, bioeroded, and fragmented) due to their long residence time in the Taphonomic Active Zone (TAZ). Few of the benthic species have a wide geographic distribution (e.g., Oscillopha dichotoma), which generally imply low sea-level. In contrast, ammonites have been precariously recorded from Africa, Europe, and Asia in addition to South America, outlines a cosmopolitan attitude. • The Coniacian-Santonian in the Eastern Desert contains low diverse oyster-dominated macrofauna. • Th macrofauna lived in a harsh intertidal environment in proximal setting south of the Tethys sea. • The long resistance in the Taphonomic Active Zone (TAZ) was result in high taphonomic damage. • High Time averaging and mixing of different guilds was attributed to low sedimentation rate. • Few species have wide geographic distribution due to the general sea-level lowstand. [ABSTRACT FROM AUTHOR]

Abstract Shales of the Abeokuta Group in the Dahomey Basin yielded abundant foraminiferal tests. The study investigated sediments from three wells that were drilled for petroleum exploration: Well – X located in the offshore deep water, Orimedu-1 and Ise-2 in the coastline region to establish their Cretaceous biostratigraphic units through planktonic foraminiferal zonation. Calcareous benthonic foraminifers occur abundantly and consistently throughout the sequences in the three wells while planktonic foraminifera are more abundant in the Well X than those in the Orimedu-1 and Ise-2. The identified planktonic foraminiferal species are: Rotalipora greenhornesis, Rotalipora cushmani, Dicarinella primitiva, Praeglobotruncana helvetica, Marginotruncana sp. Heldbergella delrionensis, Helbergella planispira, Hedbergella simplex, Whitenella inonata, Whitenella baltica, Globotruncana aegytiaca, Globotruncana sp., Heterohelix reymenti, Heterohelix moremani, Heterohelix globulosa, Abathomphalus mayaroensis and occurrence of Orthokarstenina oyea, Ammobaculites corprolithiformis, Ammobaculities sp and Bolivina sp. Calcareous benthonic foraminiferal species were more abundant than the planktonic species in Orimedu-1 and Ise-2 wells. The benthonic species decrease drastically in the well-X offshore deep water where the planktonic species were most abundant. This trend may suggest an increasing water depth from near coastline to offshore regions in the Cretaceous times. Six planktonic foraminiferal zones were recognised across the three exploratory wells. These include Rotalipora greenhornesis (middle – late Cenomanian) , Helvetoglobotruncana helvetica (early – late Turonian) , Marginotruncana pseudolinneiana (late Turonian) , Marginotruncana renzi (Coniacian – Santonian) , Globotruncana calcarata (late Santonian – early Campanian) and Globotruncana aegytiaca (Maastrichtian) Zones. The Rotalipora greenhornesis and Praeglobotruncanae helvetica Zones (Cenomanian – Turonian) were correlated with the standard zones in the Tethyan regions. The Well-X indeed penetrated older Cenomanian to Turonian intervals in the investigated wells, thereby confirming the presence of older marine sequences in the Eastern Dahomey Basin contrary to previous suppositions. Highlights • The study locations cover the offshore to coastal region of Dahomey Basin, Nigeria. • Foraminifera species are abundant and well preserved in the investigated rocks. • Six Cretaceous biostratigraphic units were established through planktonic foraminifera. • Cenomanian - Turonian is an older marine units newly established in the study. [ABSTRACT FROM AUTHOR]

Abstract Sequence stratigraphic analysis has been used to support the reservoir geological modeling of the Upper Cretaceous succession of the Arshad area, Sirt Basin, Libya. Four major sedimentary cycles (1–4) can be distinguished in the succession of the Arshad area which can be related to the standard Mesozoic cycle charts. These cycles are bounded by five sequence boundaries (SB types 1 and 2). Sedimentary cycle number 1 is represented by retrogradational patterns (shale and minor carbonates) at the base of the Arshad Formation, which pinch out to the south. Sedimentary cycle number 2 comprises a prograding pattern in the lower part (Arshad Formation) passing upward into retrograding patterns of the Sirte Formation in the upper part. This cycle includes reworked clastics of the underlying (Cambro-Ordovician) Gargaf Formation. These sandstone-dominated shallow-marine facies include the principal hydrocarbon-bearing reservoirs in the study area. The sedimentary cycles nos. 3 and 4 are composed mainly of shales and limestones (Sirte and Kalash formations), representing the main hydrocarbon source rocks and cap rocks for the underlying sandstone reservoirs in the Sirt Basin. These sediments trace the sea level changes, and increasing water depth above the major Hercynian sequence boundary. These sedimentary cycles are affected by syn-depositional tectonics which control the distribution of the hydrocarbon-bearing sands plus post-depositional changes (diagenesis) which affect the reservoir quality and performance (porosity-permeability relationship). Highlights • Introduction, Methodology and data source. • Geological setting. • Interpretation from Cyclolog® patterns (surfaces and Major sedimentary cycles). • Hydrocarbon-bearing sandstone reservoirs and depositional model of the Arshad area, Sirt Basin. [ABSTRACT FROM AUTHOR]

Abstract This contribution presents a comprehensive review of the Upper Cretaceous geological evolution of Nigeria focusing on the Benue Trough and adjacent basins. It addresses the controversies regarding potential pathways of ingression during transgressive episodes that led to the establishment of the Trans -Saharan seaway. An improved understanding of the paleogeographic evolution is essential for assessing the economic potential of the region, including the Upper Cretaceous petroleum system and coal deposits, as well as groundwater and mineral resources. Two transgressive episodes connected much of Nigeria's sedimentary terrain in the Upper Cretaceous. The first transgression, which followed the opening of the Equatorial Atlantic Ocean in mid-Albian times, established the Trans -Saharan seaway that connected the Tethys and the South Atlantic oceans through an eastward route via the Benue Trough in the Turonian. This resulted in widespread deposition of commercially exploited marine limestone and clay deposits, and subordinate coal, with sediments possessing very limited groundwater resource potential. This marine connection ceased with the continent-wide Santonian inversion tectonics that led to folding, faulting, uplift, and intrusion of older strata. A second transgression, commencing in the Campanian, reestablished the Trans -Saharan seaway through a westward Bida Basin route in the Maastrichtian, culminating in widespread, mostly marginally marine conditions in the Sokoto, Bida, Anambra, and Benin basins as confirmed in this review. The influx of marine waters from the Tethys Ocean, limited in extent by the uplifted region of the southern Benue Trough brought about marginally marine conditions in the Chad Basin and the northern and central Benue Trough. Widespread deposition of coal, clay, ironstone, and good to prolific aquiferous units occurred during this time. Highlights • A Comprehensive overview of Nigeria's Cretaceous tectono-stratigraphy is presented. • Improved understanding of Nigeria's Cretaceous paleogeographic evolution. • Addressed the controversy surrounding the Maastrichtian Trans -Saharan seaway route. • Relationship between Cretaceous geology and resource potential is presented. [ABSTRACT FROM AUTHOR]

Abstract Biostratigraphy of Santonian-Danian calcareous nannofossils and planktonic foraminifera was studied in Göynük village and close surroundings located in northwest Turkey. Calcareous nannofossil and planktonic foraminifera assemblages from this time interval were investigated in detail in seven stratigraphic sections measured in the Değirmenözü Member, Yenipazar Formation and Seben Formation. The UC12 zone in the Santonian, UC13 zone, UC14a-bTP and UC15a-b-c-dTP subzones in the Campanian and UC20a-b-c-dTP subzones in the Maastrichtian were defined with nannofossil species assemblages. Planktonic foraminifera assemblages determined included Dicarinella asymetrica Total Range Zone (TRZ) from the Santonian, Globotruncanita elevata Partial-range Zone and Globotruncana ventricosa Partial-range Zone from the Campanian and Racemiguembelina fructicosa Partial-range Zone and Pseudoguembelina hariaensis Partial-range Zone from the Maastrichtian. There was a significant reduction in nannofossil species at the Cretaceous-Paleogene (K-Pg) boundary with dominance of Braarudosphaera bigelowii, Thoracosphaera sp. and Markalius inversus species and increased abundance of biserial planktonic foraminifera species. Just above this boundary in the Danian NP1 and NP2 nannofossil zones and Parvularugoglobigerina eugubina Taxon-range Zone, Parasubbotina pseudobulloides Partial-range Subzone (P1a) , S. triloculinoides Lowest Occurrence Subzone (P1b), and G. compressa/Praemurica uncinata Lowest Occurrence Subzone (P1c) were identified from planktonic foraminifera. Highlights • Detailed nannofossil and planktonic foraminifera biostratigraphy was studied for the Değirmenözü Member, Yenipazar Formation and Seben Formation. • Seven nannofossil zones and nine planktonic foraminifera zones from the Santonian to the Danian. At the K-Pg boundary, Braarudosphaera bigelowii, Thoracosphaera sp. and Markalius inversus nannofossils are dominantly observed with biserial and smalldimension planktonic foraminifera species common. [ABSTRACT FROM AUTHOR]

Integrated palynological and palynofacies investigation based on hundreds of samples recovered from surface and subsurface successions in Sinai and the Gulf of Suez, Egypt, offer reliable data on the depositional framework of the Coniacian-Santonian Matulla Formation. The results reveal that the palynofacies contents of the three members of the Matulla Formation differ in that the lower Matulla-3 Member is Pediastrum -dominated, Matulla-2 Member is phytoclast-dominated, and the upper Mautalla-1 Member is AOM-dominated. However, some gradational mixing is observed. The assumed subdivision is very important as the Matulla Formation is a significant hydrocarbon reservoir in the Gulf of Suez, especially since this subdivision is strongly correlated with previous informal lithostratigraphic units. Furthermore, the peak occurrence of Pediastrum and its allied colonial algae that dominate the palynological assemblage, especially in the lower member of the Matulla Formation (Matulla-3), which is marginal marine, clearly implies freshwater incursions. Hence, these fossil algae are useful tracers of river runoffs as well as suspended load, enabling reconstruction of paleo-river discharge and sediment source area determination, especially if they have a promising reservoir potential, as in this case. This noteworthy record may specify an important ecozone at this time, not only in Egypt but also regionally, based on similar records from neighboring North African regions. Ultimately, the presence of Pediastrum demonstrates a sea level fall and its good preservation argues for a deposition in lowstand system tracts, which greatly conforms to sequence stratigraphic data. • Palynomorph and palynofacies content of the three members of the Matulla Formation in Sinai and the Gulf of Suez differs in that the lower Matulla-3 Member is Pediastrum -dominated, Matulla-2 Member is phytoclast-dominated and the upper Mautalla-1 Member is AOM-dominated. However, some gradational mixing is observed. • The assumed subdivision is greatly important as the Matulla Formation is a significant reservoir of the petroleum system in the Gulf of Suez, especially since this subdivision is strongly equivalent to previous informal lithostratigraphic units. • The peak occurrence of Pediastrum dominates the palynological assemblage, which is mainly marine clearly implies freshwater incursion and specifies an important ecozone at this time, not only in Egypt locally but could be also of regional significance. • The presence of Pediastrum shows sea level fall (highstand systems tracts or lowstand systems tracts), however, its good preservation points to a deposition in lowstand system tracts, which has a high agreement with sequence stratigraphy data. [ABSTRACT FROM AUTHOR]

The Upper-Cretaceous clastic succession (Nubia Group) in the area northeast of Aswan includes three rock units, from base upwards: Abu Aggag Formation (Turonian), Timsah Formation (Coniacian -Santonian) and Um Barmil Formation (Santonian – Campanian). Quartz and clay minerals are the predominant phases throughout the whole succession while feldspars are very rare. Kaolinite is overwhelming among the clay minerals, in addition to less important amounts of illite and illite/smectite. The ultrastable heavy minerals are the prevailing non- opaque phases and they significantly change in relative abundance upsection. SiO 2 , Al 2 O 3 and Fe 2 O 3 are the dominant chemical components. The statistical examination had revealed that the chemical constituents are loaded on three main geochemical trends; the siliceous, the argillaceous and the ferruginous. The enrichment factor shows that the geochemical behavior of the major and trace elements is uniform throughout the sandstones and mudstones of the Abu Aggag Formation. A significant geochemical contrast is documented between the sandstones and mudstones of both the Timsah and the Um Barmil formations. The provenance – critical elemental ratios Ti/Nb and Ti/Y are nearly constant throughout the sandstones and mudstones of the Abu Aggag Formation, and they fall within the range of granitic-granodioritic composition. The Timsah sandstones have Ti/Nb and Ti/Y ratios that are consistent with those of the Abu Aggag rocks, suggesting a similar provenance. These elemental ratios are extremely higher in the Timsah mudstones, reflecting a great influx of mafic material. The Um Barmil sandstones exhibit exceedingly dispersed values of Ti/Nb and Ti/Y, reflecting their derivation from large catchment's areas of different rock types with the eroded products being mixed in various relative proportions. The Ti/Nb and Ti/Y of the Um Barmil mudstones are closely akin to those of the Timsah mudstones suggesting analogous source. The chemical index of alteration (CIA) and the A-CN-K relation, together with the mineral composition, indicate that the siliciclastic rocks throughout the whole succession were derived mainly from deeply weathered detritus under steady-state weathering conditions. Recycling is limited in the Abu Aggag Formation and increases upwards to be more common in the Um Barmil rocks. [ABSTRACT FROM AUTHOR]

A sequence biostratigraphic analysis has been done for the Upper Cretaceous-Lower Paleogene sedimentary outcrops at Wadi Raha, Sudr El-Hetan and Wadi El-Giddi areas in west-central Sinai. The sequences are subdivided into four carbonate rock units; from base to top: the Wata, Themed, Sudr and Waseiyit formations. The biostratigraphic analysis of the studied samples led to the identification of two main planktonic foraminiferal zones, three benthic foraminiferal zones with the ammonite zone. Eleven microfacies associations are recorded in the rock units. Nine constitutes a limestone facies with one constitutes a dolostone facies and one a claystone facies. The stratigraphic data, and the facies study support the identification of three major breaks (sequence boundaries) and four depositional sequences. The depositional sequences are subdivided into four supercycles and seven cycles of 3rd order. The oldest break (∼90-88.5Ma.) exists at the top of the Wata Formation coincides with the intra Turonian drop in the global sea level with the initiation of the Syrian Arc inversion phase. The second major break (85 - ∼75Ma.) coincides with the major inversion phase and the evolution of the doubly plunging anticlines. The third major break (∼68 through ∼53Ma.) represents the last phase of the Syrian Arc inversion and complete the missing of Paleocene sequences. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous megasequence in the northern part of the Egyptian Western Desert has been classified into four 2nd order depositional sequences. These sequences started with the Cenomanian SQ-I topped by the Turonian – Santonian SQ-II. However, both SQ-III and SQ-IV represent the Campanian- Maastrichtian time span. The interpreted 2nd order SQ-I and SQ-II have been further subdivided into six smaller 3rd order sequences (SQ-1 to SQ-6). The depositional history started during the Early Cenomanian times, characterized by wide marine invasion enabled the deposition of the shallow marine Bahariya Formation (SQ-1). The Upper Cenomanian times, witnessed a rapid subsidence, simultaneously with new marine transgressive phase. This is resulted in the deposition of SQ-2, consuming the entire sediments of the Abu Roash G Member. During the Turonian – Coniacian times the northern parts of Egypt showed successive oscillating transgressive – regressive marine cycles led to equivocal sedimentary bodies of the Turonian-Coniacian Abu Roash Formation (SQ-3, SQ-4, and SQ-5). During the Santonian age, the northern parts of Egypt were subjected to tectonic crustal shortening, producing large scale folds. As a result, a new tectonically-overprinted marine depositional cycle started and marked by rapid phase of basin subsidence. This was accompanied by a deep marine invasion covered most of the northern parts of Egyptian lands, depositing the lower parts of the Khoman- B (SQ-6) under transgressive depositional conditions. By the end of Santonian cycle, the upper parts of the Khoman Formation B Member was deposited during a gradual, and slow relative sea level drop ending the deposition of SQ-6. At the beginning of the Campanian – Maastrichtian times, a new widespread sea-level rise associated with basin subsidence. Accordingly, two successive depositional cycles were thus initiated, forming SQ-III and SQ-VI sequences separated by unconformity type-2 boundary (SB-8). [ABSTRACT FROM AUTHOR]

The Campanian Hajajah Limestone Member of the Aruma Formation was formed during two regressive episodes. Each of them formed of three depositional facies, from base to top: 1) intra-shelf basin facies, made up of fossiliferous green shale and mudstone with ostracods and badly preserved foraminifers. 2) fore-reef facies, consists of hard, massive, marly coralline limestone. The upper part is rich with low divers, badly to moderate preserved, solitary and colonial corals, and, 3) back reef and near-shore facies, consists of fossiliferous sandy dolomitized, bioturbated limestone with abundant reworked corals, bivalves, gastropods, and aggregate grains. On the basis of field observations, micro-and macrofossils and microfacies analysis, the Hajajah Limestone Member was deposited in distal marine settings below storm wave base in a low-energy environment changed upward to fore-reef framework in an open marine environment with moderate to high energy conditions and terminated with shallow marine facies with accumulation of skeletal grains by storms during regression. [ABSTRACT FROM AUTHOR]

In this study, two stratigraphic sections of the Tarbur Formation named Kuh-e Gadvan and Kuh-e Tir were selected. The thicknesses of the whole sediments of the sections studied are about 1100 m of which 400 thin sections were studied. Two biozones are determined in Kuh-e Gadvan and three biozones are described in Kuh-e Tir section. According to established biozones, the age of Tarbur Formation of Kuh-e Gadvan section is assigned to Campanian-Maastrichtian and Tarbur Formation age determination shows relation to Maastrichtian-Lower Paleocene in Kuh-e Tir section. Seven major lithofacies are distinguished along two studied stratigraphic columns which are foraminifer-bioclast wackestone, algal-foraminifer- intraclast wackestone, rudist biclast wackestone, bioclast packstone, bioclast-intraclast grainstone, coral and rudist boundstone. According to the recognized lithofacies, paleoenvironment of the Tarbur formation consists of lagoon, open margin of the reef landward, margin of the reef, flat reef, and seaward margin of the reef. Comparison of studied sections allows that geologic setting had been controlled biostratigraphy and facies change. [ABSTRACT FROM AUTHOR]

Archaeological and cultural heritage of Egypt is world-known, but its geological heritage is yet to be revealed. Investigations in the central Western Desert of Egypt permitted finding a lot of unique features that can be assigned to this heritage. In the Bahariya Oasis, 10 geological heritage types are established, namely stratigraphical, paleontological, sedimentary, igneous, mineralogical, economical, paleogeographical, geomorphological, hydrological and hydrogeological, and pedological types. In the Farafra Oasis and vicinities, only geomorphological and hydrological and hydrogeological types are found. On the area between these oases, sedimentary, mineralogical, paleogeographical, and geomorphological features are established. Chalk and nummulitic limestones, invertebrate and dinosaur localities, paleoreefs and paleokarst, iron ore deposit, and peculiar landforms occur on the study territory. Taken together, these features constitute a highly diverse geological heritage that can be judged global (even if the rank of individual objects is often relatively low). This heritage is well suitable for the purpose of geotourism; for instance, thematic excursions explaining the geological evolution during the last 100 Ma are possible. Participants of such excursions can also see different facies. A geopark in the central Western Desert of Egypt would facilitate geoconservation and geotourism activities. [ABSTRACT FROM AUTHOR]

Four measured sections along the northern escarpment of the Dahar Plateau in southern Tunisia provide details of Cretaceous (Coniacian-Campanian) stratigraphy in this region of North Africa. These sections reveal various units of limestone with cross-stratification, limestone with in situ rudists, mud-supported limestone (carbonate mudstone, wackestone), argillaceous limestone, and limestone with stromatolites. These units are arranged vertically into several sequences of finer-grained limestone (mud-supported limestone, argillaceous limestone) overlain by coarser-grained limestone (limestone with cross-stratification, rudists, and/or stromatolites). Each sequence is interpreted as a shallowing upwards progression on a carbonate platform. Furthermore, cross-strqtified carbonate and beds with in situ rudists are more common in the lower parts of the measured sections, whereas units with stromatolites, argillaceous limestone, and finer-grained limestone are more common in the upper parts of the measured sections. The overall transition from the coarser-grained (higher energy) strata to the overlying finer-grained (lower energy) argillaceous strata is interpreted as having been caused by a relative fall in sea level that brought argillaceous sediment into the area. It is possible that the arrival of argillaceous sediments and the relative fall in sea level may have caused the demise of the rudist reefs. The lower interval (in which cross-stratified carbonates and in situ rudists are more common) is assigned to the Berressef Formation, whereas the upper interval (in which stromatolites, argillaceous limestone, and other fine-grained strata are more common) is assigned to the Toual Formation. Previous work suggests that the Berressef Formation is of Coniacian? to Santonian age, whereas the Toual Formation is of Campanian age. A regional cross section correlates these Cretaceous units on the Dahar Plateau with (1) rudist-bearing strata that are mapped in north–central Tunisia as the Merfeg Formation, and (2) argillaceous and marly limestone that is mapped in central Tunisia as the middle and lower Berda Formation and the middle Abiod Formation. [ABSTRACT FROM AUTHOR]

The gastropod fauna of the Upper Cretaceous Aruma Formation in central Saudi Arabia comprises fifteen species belonging to fifteen genera, fourteen families, and five clades. The species are not abundant at any individual stratigraphic level but are equally and irregularly scattered in the formation. The studied species come mainly from the Hajajah Member of Upper Cretaceous Aruma Formation in central Saudi Arabia. Calliomphalus orientalis (Douvillé, 1916); Coelobolma corbarica Cossmann, 1918; Turritella ( Torquesia ) figarii Quaas, 1902; Neoptyxis olisiponensis (Sharpe, 1850) and Otostoma ( Otostoma ) divaricatum (d’Orbigny, 1847) are recorded from the Upper Cretaceous of central Arabia for the first time. The identified species have a close affinity to the Tethyan fauna known from other parts in Asia, Africa and Europe. Herbivores and predators are the dominant trophic groups which may indicate shallow marine lagoonal and relatively open marine environment. [ABSTRACT FROM AUTHOR]

Trace element contents in isolated kerogen from Upper Cretaceous sediments within Gongila and Fika formations in the Chad (Bornu) Basin, northeastern Nigeria were determined using Inductively-coupled plasma mass spectrometer (ICP-MS), in order to infer the origin of the organic matter and the paleo-redox conditions during their sedimentation. The concentrations of the elements in the kerogen samples varied from 1.01 to 24,740 ppm. The distribution of elements shows that Fe is the most abundant element in Chad (Bornu) Basin kerogen, followed by Ce. Among the biophile elements, V is the most abundant, followed by Ni and Co in that order. Statistical evaluation of the elemental composition data shows that As, Ce, Pb, V, Cr, Fe, Co, Ni and U exhibit good positive correlations with each other. Molybdenum, on the other hand displays no obvious correlation with most of the trace elements determined including TOC, but has good positive correlation with TS and negative correlation with Tmax, Ce and Th, which suggests that the concentration of Mo decreases with increasing maturity and vice versa. Some trace element concentrations and their ratios suggest mixed marine and terrigenous source input for the organic matter (kerogen) in Chad (Bornu) Basin. More so, the concentrations of redox-sensitive elements, such as V, Ni, Cu, Cr Mo and Mn, in the kerogen samples suggest dysoxic bottom water conditions within the Gongila and Fika sediments. Cross-plots of V and Ni and V/(V + Ni) ratio also indicate that the organic matter of these samples was deposited in slightly reducing environments. [ABSTRACT FROM AUTHOR]

Highlights: [•] Taxonomic (species level) diversity of Madagascan ammonites is much lower than previously supposed. [•] Madagascan inoceramids are quite distinct. [•] Madagascan ammonites demonstrate increasing provinciality with time. [•] Madagascan inoceramids do not demonstrate any stable biogeographic pattern. [Copyright &y& Elsevier]

Upper Cretaceous tidal-flat sediments of the Abu Tartur region, Western Desert of Egypt, contain a variety of soft-sediment deformation structures (SSDSs) in the Mut Member of the Quseir Formation and the overlying Duwi Formation. Here, we document recognition of a set of SSDSs characterized by complex morphology and large size. The SSDS include: 1) water-escape structures, 2) minor recumbent, chevron, and slump folds, 3) syn-sedimentary minor faults, 4) neptunian dykes, 5) regular ball-and-pillow structures, flattened pseudo-nodules, and load casts, 6) syn-sedimentary undulations, 7) fractures and joints, 8) sand injectites, and 9) autoclastic breccia and brecciated siderite clasts. The dimensions of the SSDSs range from a few centimeters to several decimeters. Both extensional and contractional forces appear to have been involved in development of these structures. A detailed analysis of facies relationships, combined with consistent orientations of SSDSs and the regional tectonics of the target area suggests earthquakes as the triggering mechanism for sediment deformation and large-scale mass failure. The deformed strata are consistent with most of the well-known criteria of typical seismites. Thus, syn-sedimentary liquefaction was identified as the primary driving force in most of the observed deformation horizons for these Upper Cretaceous SSDSs in the Abu Tartur area. • SSDSs are abundant in the Upper Cretaceous sediments of the Abu Tartur area, Western Desert, Egypt. • Water-escape structures, minor folds, syn-sedimentary faults, and undulations are examples. • The deformed strata comply with most of the well-known criteria of typical seismites. • Earthquake shocks seem the only plausible trigger factor for these SSDSs in the studied area. • Seismites can serve as a useful tool for future paleoseismic-related studies in the studied area. [ABSTRACT FROM AUTHOR]

Abstract: The Al-Hisa Phosphorite Formation (AHP) in the Eshidiyya basin of south Jordan consists of three members, the lower member accommodates the main high grade commercial phosphorite deposits, followed upwards by the coquinoidal limestone member which is overlain by the uppermost member, the A0 member. The phosphorites in both member are granular (peloidal) type deposits. Uranium (U) and Vanadium (V), in the main phosphorites of the lower member, are 75 and 70ppm respectively as analyzed in a previous work. The distribution of the analyzed elements in this work is governed by three factors: the phosphorite (P, Ca, Na, U, V, Cd, Zn, and Sr) decreasing upwards from the lower A0 unit to the topsoil, detritals (Al, Si, Fe, Mg, K, Ga, Hf, Nb, Rb, Th, and Zr) increasing upwards, and minor carbonates (Ca, and Sr) with no obvious trend. Uranium is three times more enriched in the upper phosphorite member, the A0, relative to the lower or main phosphorite member, 234ppm versus 75ppm respectively. Vanadium is likewise enriched several times in the A0. Both elements, U and V are worth further exploration in the A0 in northern Eshidiyya basin. Thorium, Zr and Hf are relatively low. [Copyright &y& Elsevier]

The Cenomanian shallow marine succession in the Southern Galala Plateau of Egypt contains rich benthic fauna and preserves enormous information on how paleo-communities respond to fluctuating environmental conditions. Based on rock and fossil data, the Galala Formation was interpreted to be the result of deposition on a tide-dominated homoclinal ramp. Three main facies associations representing three depositional environments (intertidal, shallow subtidal, and deep subtidal) were recognized. Three distinct macroinvertebrate associations corresponding to these environments and dominated mainly by oysters were quantitatively identified. They show a gradational vertical increase in diversity as well as in the infaunal and mobile species. This trend can be attributed to the Cenomanian sea-level rise, where harsh marginal marine environments in the middle Cenomanian became more stable toward the latest Cenomanian. Sea flooding may have eliminated barriers, enhanced water circulation, and stopped hyperpycnal flow and/or terrigenous flux. Consequently, oxic mesotrophic conditions may have prevailed and siliciclastic starvation may have concentrated fossil materials, and therefore, diversity increased. Based on the vertical and lateral changes of the facies stacking pattern, two main parasequence types were recognized, the first includes deep subtidal deposits changed upwards to shallow subtidal and the second includes shallow subtidal deposits that pass upward into intertidal. Moreover, two and one-half third-order mixed sequences were identified and correlated to their regional and global counterparts. • The Galala Formation was deposited on a tide-dominated homoclinal ramp. • Intertidal, shallow subtidal, and deep subtidal depositional environments were recognized. • Within these environments, three distinct macroinvertebrate associations were identified. • Vertical increase in diversity and infaunal mobile taxa was attributed to eustatic sea level rise. • Third order depositional sequences were identified and correlated to their counterparts. [ABSTRACT FROM AUTHOR]

The Abu El Gharadiq Basin (AGB) is one of the largest Cretaceous rift basins in the northern district of the Western Desert of Egypt. The AGB underwent tectonic inversion in the Upper Cretaceous through horizontal shortening in the NW-SE direction. Detailed interpretation of seismic sections across discrete regions of this basin shows that the rocks deformed in two different depth-related deformation styles, which are partitioned across the base of the so called Bahariya Formation of Cenomanian age. The deeper, pre-Cenomanian rock units show contractional deformation forming tight folds and related fabrics while shallower, post-Cenomanian rock units display features of extensional deformation. These are essentially shallowly undulating open folds, associated with conjugate normal faults and tensional fractures. The deeper pre-Cenomanian tight anticlines pierce the upper rock units as diapiric-like intrusions that are seen on the seismic sections as hazy regions. We infer that the two different deformation styles above and below the Cenomanian rocks occurred simultaneously. The hazy regions on the seismic sections may result from lateral flow of shale rocks that give rise to chaotic structures near the anticlines. Mechanical anisotropy across the Cennomanian rock unit is inferred to be the main cause of simultaneous emergence of contractional and extensional deformations. Re-evaluation of fracture patterns of the northern rift basins in the Western Desert implies that the AGB originated in an extensional stepover region of a discrete, ENE-WSE trending, shear zone whose margins underwent inversions, developing two parallel thrust-dominated ridges, namely the crustal scale Kattaniya and Qattara-Alamein ridges. [Display omitted] • Interpretations of two different deformation styles across the Abu El Gharadig Basin. • Pre- and post-Cenomanian rocks experienced contractional and extensional deformations. • The base of Bahariya Fm. represents the surface of strain portioning. • Competency contrasts across the surface of strain partitioning at confining pressure and vertical stress interpret. [ABSTRACT FROM AUTHOR]

The Anza tracksite, discovered in 2013, is one of several sites in the Western High Atlas of Morocco that contain well-preserved and diverse dinosaur and pterosaur trackways. The occurrence of rare tracks at Anza combined with the stratigraphic position, coastal location, and easy accessibility, have inspired the scientific community, non-governmental organizations, and local inhabitants, to increase public awareness of the scientific, geoeducational, and ichnological heritage potential of the tracksite, as well as to develop strategies for site conservation and protection. • Presents the dinosaur and pterosaur tracksite at Anza as a potential geosite. • Describes the geographic and geologic context of the Anza tracksite. • Summarizes the paleontological importance of the tracks. • Describes the educational/touristic value and protection/conservation efforts. [ABSTRACT FROM AUTHOR]

Understanding the response of the benthic invertebrates to long-term sea-level changes, which is possible only from the fossil record, is crucial for conservation biology. Based on integrated sedimentological and biostratigraphical data from the Cenomanian-Turonian succession of Wadi Tarfa (Eastern Desert, Egypt), a cyclic pattern, comparable to those of 2nd order sequence stratigraphy, between the community structure of the invertebrates and the sea-level fluctuations was revealed. Quantitative analysis of 1756 specimens representing 154 invertebrate genera encompassing mollusks and echinoid revealed that invertebrate communities can be classified into three different types. The first associated with the initiation of transgression (TST) and dominated mainly by opportunistic, epifaunal suspension-feeders, including gastropods and bivalves. This community is characterized by lower diversity values. The second community belonged to the maximum flooding zone (MFZ) and mainly dominated by infaunal deposit-feeders of irregular echinoids and bivalves and characterized by higher diversity. The last community is less diverse, dominated by few epifaunal-suspension feeders and occupying the late highstand system tract (HST). The lower diversity values during the early TST/late HST may result from the persistence of waves/the higher sedimentation rates. Consequently, only opportunistic taxa flourished. In contrast, diversity increases with flooding and is at a maximum and dominance at a minimum at the transgression peak (MFZ). Here, the high diversity, which is commonly augmented by time-averaging, most likely contributed also to the environmental stability, which increases with flooding. Accumulation of biogenic hardparts in combination with low rates of sedimentation may increase substrate heterogeneity and thus increases beta diversity (niche differentiation). The cyclic pattern of the community attributes results from the hydrodynamic setting accompanying the sea-level changes. The role of ecoenvironmental and taphonomic mechanisms in shell concentrations are also discussed. Image 1 • The community structure has a cyclic pattern comparable to the sequence stratigraphic architecture. • Biodiversity increase with increasing flooding and be of maximum at the maximum flooding zone. • The faunal variations are driven mainly by sea-level fluctuations and hydrodynamics. • The ecoenvironmental and taphonomic mechanisms in shell concentrations were specified. [ABSTRACT FROM AUTHOR]

The Anambra Basin has become a subject of interest in recent years, following renewed search for hydrocarbon in Nigeria's inland sedimentary basins to increase its reserve base. Although there are extensive studies on different hydrocarbon aspects of the basin, there are currently no published studies on the assessment of potential subsurface reservoirs. This study evaluates the reservoir properties of the Upper Cretaceous (Campanian to Maastrichtian) Anambra Basin, within a sequence stratigraphic framework, using wireline-log data. Four depositional sequences (SEQ-1, SEQ-2, SEQ-3, and SEQ-4, from oldest to youngest) were interpreted, each bounded by two sequence boundaries. They span in age from 83 Ma to 63 Ma (20 Myr duration), and overall record an initial transgression, then subsequent regression, aggradation, and final transgression. The cross-plots and computed petrophysical properties suggest that there are significant spatial and temporal variations in reservoir parameters in the basin, with some predictable trends, as shown by generated isoparametric maps. Preliminary assessment further suggests that the main controls on reservoir property variations are the depositional facies, burial depth, and diagenetic processes (compaction and cementation). A new method of ranking the reservoir potential of interpreted depositional sequences showed that the best ranked sequence is SEQ-4 (chance of success, CoS = 0.73/0.9), while the least ranked sequence is SEQ-1 (CoS = 0.45/0.9). This study therefore provides a framework within which additional well data should be made available, to allow a robust assessment of the trends of and controls on the spatio-temporal variations in petrophysical properties, in order to better predict reservoir quality distribution, and guide future exploration in this frontier basin. Image 1 • Cross-plots discriminate lithologic composition of four depositional sequences. • Reservoir property variation controlled by facies, burial depth, and diagenesis. • New method proposed for ranking reservoir potential of the depositional sequences. [ABSTRACT FROM AUTHOR]

The present study aims to investigate the availability of using clay materials of the, upper Cenomanian El Heiz, Turonian-Santonian Naqb El-Sillim and Oligocene Radwan Formations in the Bahariya Oasis for the first time to use in the ceramic industry, especially vitrified clay pipes for sewers and drainage. Many technological methods were used to evaluate these raw materials, including mineralogical and geochemical data involving major and trace elements. Thermal analysis was also performed to study the properties of raw materials. Analyses on some physical and chemical properties was also done to evaluate clay properties, as shrinkage, water absorption, bulk density, apparent porosity and chemical resistance. Based on the results of chemical and mechanical properties, the Radwan Formation yielded the best results with respect to pipe manufacturing. It also had the best results for plasticity. This analysis enables to evaluate the percentage of water needed for its Formation and has a profound effect in reducing the energy needed for the drying process. • The clay materials in the Bahariya Oasis studied for their suitability in vitrified clay pipes industry. • Chemical, mineralogical and thermal analyses were also performed to study the properties of raw materials. • The Radwan Formation yielded the best results with respect to pipe manufacturing. • It also had the best results for physical properties. [ABSTRACT FROM AUTHOR]