Geochemical Maturity and Paleo-Weathering Indices of Sedimentary Succession in JVField Greater Ughelli Depo-Belt Niger Delta Basin

This study evaluates the geochemical maturity and paleo weathering indices of X well JV-Field, Greater UghelliDepo belt Niger Delta Basin, using reflected light microscope and geochemical proxies. The data obtained identified three lithofacies units as Sand, Shale, and Shaly sand facies .The application of source area weathering using Chemical index of alteration (CIA) and Chemical index of weathering (CIW) values for the sampled intervals ranges from (48.6-94.9%) and (60.6-96.7%), and have median values of (83.2 and 90.3) % respectively which is an indication of high weathering at the source. The values are variable and it may be as a result of multiple provenances of the sediments which have variable proportions of source area weathering and related processes or may be due to low concentrations of the alkalis and alkaline earth elements. However, all the samples excluding one with depth (12430ft) show CIA and CIW values greater than 70% indicating high (intensive) weathering either at the source or during transportation before deposition .From the high alteration indices value recorded from the sampled intervals, it can be inferred that the sediments are geochemically and texturally mature

Palynological zonation of oligocene to early miocene sediments of greater Ughelli Depobelt, Niger Delta Basin

Palynological zonation of Oligocene to Early Miocene sediments of Greater Ughelli Depobelt Niger Delta Basin was carried out using One hundred and ninety (190) ditch cutting samples ranging from 20ft.-11,820ft. (6.09m- 3603.7m), by identifying the different species of palynomorphs present as well as using stratigraphic significant diagnostic palynomorphs to age date and zone the well section, Nine hundred and sixty four (964) species of palynomorps were recovered.Nine hundred and fifty four (954) were miospores(pollen and spore) and ten(10) were Dinocysts.The presence of diagnostic palynomorphs such as Praedapollis africanus, Peregrinipollis nigericus, Retibrevitricolporites obodoensis aided in the establishment of the age and three P-zones in the well. The age of the well section range from Oligocene to Early Miocene.The P-zones established are P560, P580 and P620 zones. P620 and P580 Zones were lumped together and was established based on the occurrence of Top Pradapollis africanus at 4500ft and quantitative base of Peregrinipollis nigericus at 7620ft.This zone were lumped together because Top/FDO Cicatricosisporites dorogenesis (30)/Gemmatriporites sp (573) which represents the base of P620 zone and top of P580 zone were undefined. P560 Zone was defined by the appearance of quantitative base Peregrinipollis nigericus at 7620ft and increase Retibrevitricolporites obodoensis at 11580ft.Keywords: Lithozones; Niger delta Basin; Palynomorphs; Oligocene to Early Miocene; Depobel

Chemical Classification of Sediments in JVX -Well, Greater Ughelli Depobelt Niger Delta Basin, Nigeria

This study evaluate the Chemical classification of sediments in JVX well, Greater Ughelli Depo belt Niger Delta Basin. Samples collected from different intervals were analyzed using geochemical proxies. Agbada Formation was suggested for the sampled intervals due to the presence of shaleand sand intercalations. lithofacies units gotten from sampled intervals are Sand, Shale and Shaly sand facies . The sands are milky in colour, translucent to opaque, medium to coarse grain, subangular to subrounded and are moderately sorted while the shales are Grey in colour,fissile with the presence of lignite streak and calcareous materials.The geochemical studies of the sediments revealed that SiO2 is the dominant oxide followed by Al2O3 and Fe2O3 which constitutes over 90% while others like CaO, K2O, TiO2, Na2O and MgO constitute 10%. The sediments were classified as Fe-shale, Fe-sand and Quartz arenite. Samples that plotted in the quartz arenites region suggests an intense degree of weathering and reworking. The SiO2/Al2O3 ratios for the sediments in the well are appreciably high indicating that the samples have been heavily weathered, evidenced from the enrichment of quartz and depletion of feldspars. Also, the relatively high concentrations of Fe2O3 and TiO2 is an indication of iron-titanium minerals such as haematite and anatase retiles

Paleo-environmental reconstruction of oligocene to early miocene sediments of Greater UghelliDepobelt, Niger Delta Basin

Paleoenvironmental study of Oligocene to Early Miocene sediments of Greater UghelliDepobelt Niger Delta Basin were carried outusing foraminiferal micropaleontology as geologic tools.Fifty (50) ditch cutting samples ranging from 20ft.-11,820ft (6.09m-3603.7m) was used with the aim of establishing thepaleo-environment of the well. A total of twenty six (26) foraminiferal species were recorded, most of the species recorded are calcareous and arenaceous benthic foraminiferal species while planktonic foraminiferal species are generally scarce in the well. The non-recovery of planktonic and the general poor recovery of foraminiferal species might be due to environmental factor. The foraminiferal abundances revealed two varying depositional environment which are Continental to Marginal Marine and Proximal to distal Inner Neritic environment. These deductions were based primarily on benthic foraminiferal assemblage, their abundance and diversity. The presence or absence of planktonic foraminifera also helped in deciphering open ocean environments.The Continental to Marginal Marine setting range from 1640ft to 11,100ft due to non-recovery to rare foraminiferal species recorded within this interval while the Proximal to Distal Inner Neritic ranges from 11,160ft to 11,760ft with the presence of few foraminiferal species consisting of rare benthic foraminiferal species and scarcity of planktonics foraminiferal species indicating deposition in a shallow water, suggesting sediments deposition is fluctuating between proximal to distal Inner Neritic.Keywords: foraminiferal; Proximal to Distal Inner Neritic;Paleoenvironment; Niger Delta Basin; Depobel