Current palynologic and stratigraphic data presented in this paper, show the existence of Upper Tertiary to Lower Quaternary deposits in the Mbere and Djerem basins. The upper part, so called “Late Continental” deposits encounters different palynomorphs with angiosperms (Gramineae, Chenopodiaceae, Malvaceae and Compositeae), spores, fungi, gymnosperm and freshwater algae, which are of Late Tertiary/Quaternary aspect. No marine palynomorph is reported. The border faults
might have reworked at several occasions during post-cretaceous periods, probably during the
Oligocene/Miocene as indicated by the Oligo-Miocene volcanic products associated with the “Late
Continental” sedimentary series. Three periods of sedimentation can be distinguished, interbeded by
erosional and volcanic phases.

Aptian and Albian palynofloras were extracted from a Lower Cretaceous succession penetrated by the Kabrit-1 borehole, northern Gulf of Suez. Representatives of Murospora and pollen such as Afropollis operculatus and A. zonatus are diagnostic of the Aptian palynoflora.
Afropollis jardinus, Crybelosporites pannuceus spores and elaterate pollens such as Elaterosporites klaszii and E. verrucatus date the overlying succession as Albian and Upper Albian–lower Cenomanian? Reyrea polymorphus and Cicatricosisporites sinuosus co-occur
only in the Albian. The palynofloras are suggestive of shallow marine environment and warm humid palaeoclimate, as directly inferred from the nature and composition of the palynomorph content, which is dominated by pteridophytic spores, along with marine dinoflagellates. The occurrence of rich terrestrial influx of palynomorphs and palynodebris suggests proximity of the depositional sites to source vegetation. The vertical distribution of terrestrial versus marine palynomorphs cannot reflect contemporaneous regressive/transgressive cycles during deposition of the different rock units. The Kabrit-1 palynoflora share general features of the Northern Gondwana province.

Aptian and Albian palynofloras were extracted from a Lower Cretaceous succession penetrated by the Kabrit-1 borehole, northern Gulf of Suez. Representatives of Murospora and pollen such as Afropollis operculatus and A. zonatus are diagnostic of the Aptian palynoflora.
Afropollis jardinus, Crybelosporites pannuceus spores and elaterate pollens such as Elaterosporites klaszii and E. verrucatus date the overlying succession as Albian and Upper Albian–lower Cenomanian? Reyrea polymorphus and Cicatricosisporites sinuosus co-occur
only in the Albian. The palynofloras are suggestive of shallow marine environment and warm humid palaeoclimate, as directly inferred from the nature and composition of the palynomorph content, which is dominated by pteridophytic spores, along with marine dinoflagellates. The occurrence of rich terrestrial influx of palynomorphs and palynodebris suggests proximity of the depositional sites to source vegetation. The vertical distribution of terrestrial versus marine palynomorphs cannot reflect contemporaneous regressive/transgressive cycles during deposition of the different rock units. The Kabrit-1 palynoflora share general features of the Northern Gondwana province.

Aptian and Albian palynofloras were extracted from a Lower Cretaceous succession penetrated by the Kabrit-1 borehole, northern Gulf of Suez. Representatives of Murospora and pollen such as Afropollis operculatus and A. zonatus are diagnostic of the Aptian palynoflora.
Afropollis jardinus, Crybelosporites pannuceus spores and elaterate pollens such as Elaterosporites klaszii and E. verrucatus date the overlying succession as Albian and Upper Albian–lower Cenomanian? Reyrea polymorphus and Cicatricosisporites sinuosus co-occur
only in the Albian. The palynofloras are suggestive of shallow marine environment and warm humid palaeoclimate, as directly inferred from the nature and composition of the palynomorph content, which is dominated by pteridophytic spores, along with marine dinoflagellates. The occurrence of rich terrestrial influx of palynomorphs and palynodebris suggests proximity of the depositional sites to source vegetation. The vertical distribution of terrestrial versus marine palynomorphs cannot reflect contemporaneous regressive/transgressive cycles during deposition of the different rock units. The Kabrit-1 palynoflora share general features of the Northern Gondwana province.

Abstract. Diverse and well preserved palynofloras were recognized in the Lower Cretaceous succession penetrated by well Siqeifa 1-X in northern Egypt. Dinoflagellate cysts such as Subtilisphaera senegalensis
was regarded, with the spores Impardecispora apiverrucata and Aequitriradites spinulosus, as important Berriasian to Barremian species.
Afropollis operculatus/zonatus pollen and spores such as Balmeisporites holodictyus, Trilobosporites laevigatus and Duplexisporites generalis are diagnostic of Aptian. The lowest occurrences of the pollen
Afropollis jardinus, the spore Crybelosporites pannuceus and elaterates such as Elaterosporites klaszii, Elaterocolpites castelainii and Elateroplicites
africaensis characterize the Albian/lower Cenomanian interval. The palynofloras enabled the recognition of five spore-pollen and four dinoflagellate zones, which are correlated with regional records, mainly from Egypt and Libya. The vertical distribution of terrestrial and marine palynomorphs, along with palynodebris, reflects two regressive marginal marine cycles during Berriasian-Barremian and Albian-lower Cenomanian times whereas the Aptian witnessed a transgressive open marine (inner shelf) environment. A warm humid palaeoclimate was
inferred during deposition of the investigated succession of the borehole, in contrast to the known warm arid to semi-arid climate, suggested for the Northern Gondwana Realm during Early Cretaceous
times. This is probably due to the palaeogeographic position of Egypt during Early Cretaceous times or, to a local reason. Palynofloras from Siqeifa 1-X borehole, with Afropollis pollen and elaterates, are of North
African aspect and share the broad characteristics of the ‘‘Albian-Cenomanian Elaterates Province’’ of Herngreen et al. (1996). Abundance of spores and araucariacean pollen are transitional features between those in North Gondwana and Southern Laurasia but, unlikely, typical transitional assemblages lack bisaccates conifers and have Gleicheniaceae
spores.

A palynological analysis has been conducted on the Cretaceous sediments of the Abu Tunis 1x borehole, in the northern Western Desert, Egypt. The palynomorphs recovered have been analysed both qualitatively and quantitatively, and permit a refinement of the original stratigraphy with the identification of four time-rock units. These have been divided into four informal sporomorph units and one dinoflagellate cyst palynozone. These biozones are, from oldest to youngest: the Afropollis jardinus-Tricolporopollenites-Elaterosporites klaszii Assemblage Zone (early–mid Albian), the Elaterosporites verrucatus-Sofrepites legouxae-Cretacaeiporites Assemblage Zone (late Albian–early
Cenomanian), the Sofrepites legouxae Partial Range Zone (early–?mid Cenomanian), the Proteacidites cf. africaensis Total Range Zone (mid–late Cenomanian) and the Canningia senonica Total Range Zone (early? Santonian). A barren interzone has been identified immediately below the youngest palynozone, and this may be related to the unfavourable lithology (i.e., limestone and dolostone). The absolute abundances of spores and pollen represent the first quantitative description of an Egyptian Albian–Cenomanian palynofloral, a flora that is characteristic of the Albian–Cenomanian Elaterate Phytogeographical Province. The early Santonian palynoflora is exclusively marine phytoplankton; terrestrial palynomorphs representative of the Senonian Palmae Province are completely absent. The quantitative and semi-quantitative distributions of Afropollis jardinus are compared with similar semi-quantitative distributions of this species from other wells in the northern Western Desert of Egypt, and
this permitted the identification of a mid Albian–early Cenomanian Afropollis jardinus ‘acme’ as an important local biostratigraphical event in the mid Cretaceous.

The current work investigates the hydrocarbon potentiality of the upper Jurassic–lower Cretaceous rocks in the Marib-Shabwah Basin, Central Yemen, through the Sabatayn-1 well. Therefore, palynological and organic geochemical analyses were carried out on 37 ditch cutting and
12 core samples from the well. Palynofacies analysis of the Madbi (late Oxfordian–early Tithonian) and Nayfa (Berriasian–Valanginian) Formations sediments indicates deposition of their organic-rich shale, calcareous shale and marl in middle to outer shelf environments under dysoxic–anoxic conditions, containing mainly kerogen of types II to III. However, the shales of the lower Sabatayn (Tithonian) Formation were deposited in an inner shelf environment of prevailing dysoxic–suboxic conditions, and show kerogen types III to II. Regional warmand relatively dry palaeoclimate but with local humid conditions developed near the site of the well is thought to have prevailed during deposition of the studied well sediments. The geochemical analyses of the Madbi Formation show higher total organic carbon content (TOC) than the overlying Sabatayn and Nayfa formations: it is varies between 1.2 and 7, and with average 4 wt% TOC, and the obtained S2 values (~ 3–10, average 7 mg HC/g rock) indicates that the Madbi Formation is mainly good source rock. It shows a good petroleum potential of 4–11 mg HC/g dry rock, and the Rock-Eval pyrolysis indicates mainly kerogen types II to III (oil to gas prone) of hydrogen index values (132–258, and only one sample from Lam Member is of 360 and average 215 mg HC/g TOC). The thermal maturation parameters as Tmax (425–440 °C), production index (average 0.13 mg HC/g rock) and thermal alteration index (2 to 2+) reflected that this formation is present at margin of maturation to early mature stage oil window. So, the Lam Member (upper part) of the Madbi Formation is considered the main hydrocarbon (oil and gas) source rock in the Marib-Shabwah Basin. Accordingly, we predict that the Meem Member is an active source for gas and oil accumulations in the overlying sandstone reservoir of the Sabatayn Formation in the Sabatayn-1 well.

The current work investigates the hydrocarbon potentiality of the upper Jurassic–lower Cretaceous rocks in the Marib-Shabwah Basin, Central Yemen, through the Sabatayn-1 well. Therefore, palynological and organic geochemical analyses were carried out on 37 ditch cutting and
12 core samples from the well. Palynofacies analysis of the Madbi (late Oxfordian–early Tithonian) and Nayfa (Berriasian–Valanginian) Formations sediments indicates deposition of their organic-rich shale, calcareous shale and marl in middle to outer shelf environments under dysoxic–anoxic conditions, containing mainly kerogen of types II to III. However, the shales of the lower Sabatayn (Tithonian) Formation were deposited in an inner shelf environment of prevailing dysoxic–suboxic conditions, and show kerogen types III to II. Regional warmand relatively dry palaeoclimate but with local humid conditions developed near the site of the well is thought to have prevailed during deposition of the studied well sediments. The geochemical analyses of the Madbi Formation show higher total organic carbon content (TOC) than the overlying Sabatayn and Nayfa formations: it is varies between 1.2 and 7, and with average 4 wt% TOC, and the obtained S2 values (~ 3–10, average 7 mg HC/g rock) indicates that the Madbi Formation is mainly good source rock. It shows a good petroleum potential of 4–11 mg HC/g dry rock, and the Rock-Eval pyrolysis indicates mainly kerogen types II to III (oil to gas prone) of hydrogen index values (132–258, and only one sample from Lam Member is of 360 and average 215 mg HC/g TOC). The thermal maturation parameters as Tmax (425–440 °C), production index (average 0.13 mg HC/g rock) and thermal alteration index (2 to 2+) reflected that this formation is present at margin of maturation to early mature stage oil window. So, the Lam Member (upper part) of the Madbi Formation is considered the main hydrocarbon (oil and gas) source rock in the Marib-Shabwah Basin. Accordingly, we predict that the Meem Member is an active source for gas and oil accumulations in the overlying sandstone reservoir of the Sabatayn Formation in the Sabatayn-1 well.

Palynological and palynofacies analyses were carried out on some Cretaceous samples from the Qattara Rim-1X borehole, north Western Desert, Egypt. The recorded palynoflora enabled the recognition of two informal miospore biozones arranged from oldest to youngest as Elaterosporites klaszii-Afropollis jardinus Assemblage Zone (mid Albian) and Elaterocolpites castelainii–Afropollis kahramanensis Assemblage Zone (late Albian–mid Cenomanian). A poorly fossiliferous but however, datable interval (late Cenomanian–Turonian to ?Campanian–Maastrichtian) representing the uppermost part of the studied section was also recorded. The palynofacies and visual thermal maturation analyses indicate a mature terrestrially derived organic matter (kerogen III) dominates the sediments of the Kharita and Bahariya formations and thus these two formations comprise potential mature gas source rocks. The sediments of the Abu Roash Formation are mostly dominated by mature amorphous organic matter (kerogen II) and the formation is regarded as a potential mature oi source rock in the well. The palynomorphs and palynofacies analyses suggest deposition of the clastics of the Kharita and Bahariya formations (middle Albian and upper Albian–middle Cenomanian) in a marginal marine setting under dysoxic–anoxic conditions. By contrast, the mixed clasticcarbonate sediments of the Abu Roash Formation (upper Cenomanian–Turonian) and the carbonates of the Khoman
Formation (?Campanian–Maastrichtian) were mainly deposited in an inner shallow marine setting under prevailing suboxic–anoxic conditions as a result of the late Cenomanian and the Campanian marine transgressions. This environmental change from marginal to open (inner shelf) basins reflects the vertical change in the type of the organic matter and its corresponding hydrocarbon-prone types. A regional warm and semi-arid climate but with a local humid condition developed near/at the site of the well is thought to have prevailed.

Palynological and palynofacies analyses were carried out on some Cretaceous samples from the Qattara Rim-1X borehole, north Western Desert, Egypt. The recorded palynoflora enabled the recognition of two informal miospore biozones arranged from oldest to youngest as Elaterosporites klaszii-Afropollis jardinus Assemblage Zone (mid Albian) and Elaterocolpites castelainii–Afropollis kahramanensis Assemblage Zone (late Albian–mid Cenomanian). A poorly fossiliferous but however, datable interval (late Cenomanian–Turonian to ?Campanian–Maastrichtian) representing the uppermost part of the studied section was also recorded. The palynofacies and visual thermal maturation analyses indicate a mature terrestrially derived organic matter (kerogen III) dominates the sediments of the Kharita and Bahariya formations and thus these two formations comprise potential mature gas source rocks. The sediments of the Abu Roash Formation are mostly dominated by mature amorphous organic matter (kerogen II) and the formation is regarded as a potential mature oi source rock in the well. The palynomorphs and palynofacies analyses suggest deposition of the clastics of the Kharita and Bahariya formations (middle Albian and upper Albian–middle Cenomanian) in a marginal marine setting under dysoxic–anoxic conditions. By contrast, the mixed clasticcarbonate sediments of the Abu Roash Formation (upper Cenomanian–Turonian) and the carbonates of the Khoman
Formation (?Campanian–Maastrichtian) were mainly deposited in an inner shallow marine setting under prevailing suboxic–anoxic conditions as a result of the late Cenomanian and the Campanian marine transgressions. This environmental change from marginal to open (inner shelf) basins reflects the vertical change in the type of the organic matter and its corresponding hydrocarbon-prone types. A regional warm and semi-arid climate but with a local humid condition developed near/at the site of the well is thought to have prevailed.