Papers by Aitalokhai Edegbai
The late Campanian-middle Maastrichtian (upper Cretaceous) Mamu Formation is very important in th... more The late Campanian-middle Maastrichtian (upper Cretaceous) Mamu Formation is very important in the geological development of the Nigerian sector of the West African Rift System (WARS), as it provides supporting evidence for the Maastrichtian re-establishment of the Trans-Saharan Seaway (Tethys-South Atlantic Ocean connection). In addition to providing useful insight into the prevailing paleoceanographic condition of the Trans-Saharan Seaway, xi mit Landpfanzenmaterial (Organofazies C und CD), als auch distale Bereiche, in denen tonigere Lithologien unter höherer Salinität abgelagert wurden. In diesem Faziesbereich ist zudem eine Mixtur aquatisch-stämmigen und Landpflanzen-stämmigen organischen Materials zu dokumentieren (Organofazies BC und C). Der Ablagerungsraum war vorwiegend gut durchlüftet. Allerdings belegen Palynofazies, sedimentäre Mikrotextur und Fe-S-TOC Daten eine verstärkte Pyritbildung die in zwei Phasen erfolgte. Eine erste syngenetische Pyritisierung erfolgte durch dissimilatorische Sulfatreduktion, wobei eine zweite Phase auf spät-diagenetische Prozesse zurückzuführen ist. Letztere kann als die Hauptphase der Pyritbildung angesehen werden. Zudem zeigen die Lithologien Campano-Maastrichtian Altes einen hohen Grad an chemischer Alteration, was auf ein vorwiegend warmes und humides Klima schließen lässt. Detritische Sediment-Kompartimente stammen von prä-Santonischen Lithologien, als auch von silizium-reichen Magmatiten und Metamorphiten. Daten aus Aufschlüssen und Kernbohrungen dokumentieren eine hohe räumliche Variabilität der Mamu Formation, welche im Eintrag klastischen Materials und derer Mischung aus drei unterschiedlichen Liefergebieten begründet ist. Diese können anhand ihrer chemischen
Ife Journal of Science, 2015
The source rock potential of Maastrichtian Dark Shale in the South Eastern flank of the Anambra B... more The source rock potential of Maastrichtian Dark Shale in the South Eastern flank of the Anambra Basin has been extensively studied, with very little or no research carried out in the South Western flank (Benin flank). To this end, outcrop samples of the Maastrichtian Dark Shale obtained from Auchi, Uzebba, Sobe, Agbanikaka and Ikabigbo, SW flank, were assessed using Rock-Eval Pyrolysis and Palynofacies analysis techniques. Results of this preliminary assessment show that organic richness ranges from good to excellent; plot of HI against Tmax shows that its source quality is predominantly of Type III (gas prone Kerogen). Kerogen analysis reveals Phytoclast palynofacies (vitrinite) as the most abundant palynofacies (over 75%), about 20% miospore and less than 5% dinocysts recorded. This also depicts dominant Type III (gas prone) kerogen and a Terrestrial-Transitional depositional environment for the shales. Thermal maturity based on Tmax and Spore colour index suggests largely immature to early mature kerogens. Although a low thermal maturity exists at the surface, this study reveals that the Maastrichtian Dark Shale in the SW Anambra Basin/Benin flank has good source potential (sufficient organic richness, mainly of gas prone type III kerogen) and compares favourably with published data from the SE. Furthermore, it is anticipated that the right thermal maturity required for hydrocarbon generation may be attained at depths or close to regional fractures, which is the case in the SE Anambra Basin.
The source rock potential of Maastrichtian Dark Shale in the South Eastern flank of the Anambra B... more The source rock potential of Maastrichtian Dark Shale in the South Eastern flank of the Anambra Basin has been extensively studied, with very little or no research carried out in the South Western flank (Benin flank). To this end, outcrop samples of the Maastrichtian Dark Shale obtained from Auchi, Uzebba, Sobe, Agbanikaka and Ikabigbo, SW flank, were assessed using Rock-Eval Pyrolysis and Palynofacies analysis techniques. Results of this preliminary assessment show that organic richness ranges from good to excellent; plot of HI against Tmax shows that its source quality is predominantly of Type III (gas prone Kerogen). Kerogen analysis reveals Phytoclast palynofacies (vitrinite) as the most abundant palynofacies (over 75%), about 20% miospore and less than 5% dinocysts recorded. This also depicts dominant Type III (gas prone) kerogen and a Terrestrial -Transitional depositional environment for the shales. Thermal maturity based on Tmax and Spore colour index suggests largely immature to early mature kerogens. Although a low thermal maturity exists at the surface, this study reveals that the Maastrichtian Dark Shale in the SW Anambra Basin/Benin flank has good source potential (sufficient organic richness, mainly of gas prone type III kerogen) and compares favourably with published data from the SE. Furthermore, it is anticipated that the right thermal maturity required for hydrocarbon generation may be attained at depths or close to regional fractures, which is the case in the SE Anambra Basin.
Drafts by Aitalokhai Edegbai
Santonian units [9]. Besides the aforementioned hypotheses, further data and reports, support tha... more Santonian units [9]. Besides the aforementioned hypotheses, further data and reports, support that more than one provenance region exists. Petters [28] opined that sediment contribution from the palaeo-River Niger and the Southern Benue Trough exists. This hypothesis has been somewhat reinforced by recent palaeogeographic and palaeo-drainage models [11][12]. Tijani [8], who undertook textural and geochemical analysis of the Ajali Formation, hypothesized a sediment provenance in the Adamawa-Oban Massif highlands as well as from the pre-Santonian strata of the Southern Benue Trough. Our previous findings in the western segment of the Anambra basin [9] using high resolution multidisciplinary techniques suggested some detrital contribution from basement complex rocks in the southwest (minor) as well as the pre-Santonian rocks (major). It is against this background that we undertook this study, which seeks to investigate
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Papers by Aitalokhai Edegbai
Drafts by Aitalokhai Edegbai