Inorganic Geochemical Study of the Siliciclastic Sediments penetrated by Ash-3 Well in the Greater Ughelli Depobelt, Niger Delta Basin, Nigeria

Inorganic geochemical study of the siliciclastic sediments penetrated by Ash-3 Well was undertaken in order to classify the siliciclastic sediments, determine the provenance area, tectonic setting and the environment of deposition of the study area. Twenty eight (28) ditch cutting samples within the interval of 15ft to 11430ft were obtained for Xray fluorescence analysis to determine the major oxides composition. Using Herron’s plot for classification shows that the siliciclastic sediments were classified into Fe-shale, Fe-sand and quartz arenites fields. Roser and Korsch’s discriminant function diagrams for provenance signature and tectonic setting show quartzose sedimentary provenance and passive margin tectonic setting fields respectively. The environment of deposition from inorganic geochemical analysis shows that the sediments were deposited with in the continental and transitional environments

Lithofacies Characterization and Quantitative Mineralogical Analysis of the sediments from Sahaiawei-1Well in the Northern Delta Depobelt of the Niger Delta Basin

The sediments of Sahaiawei-1 Well in the Northern Delta Depobelt are represented by sand and shale alternation. Lithofacies characterization and X-ray diffraction technique were used to characterize the sediments from the well in order to characterize the lithofacies, identify the minerals present, determine environment of deposition and identify potential zones for hydrocarbon exploitation. The lithofacies characterization was based on the textural properties, mineralogical composition, fossil content, homogeneity and heterogeneity of the lithofacies units of the well. The lithofacies analysis for Sahaiawei-1 Well identified four (4) lithofacies types of mainly sandstone, shaly sandstone, sandy shale and shale; and fourteen (14) lithofacies zones. The result of the X-ray diffraction analysis identified the following clay minerals \u2013 kaolinite, illite/muscovite, chlorite and sepiolite; carbonates and non-clay minerals. Therefore, due to the high percentage of kaolinite in Sahaiawei-1 Well (2% to 39.87%), it could be concluded that pore filing kaolinite may have more effect on the reservoir quality than the pore bridging illite and pore lining chlorite

Use of Sedimentological and Geochemical Parameters to Evaluate the Lithologies and Geochemical (Na/Zn and K/Mn) Ratios of OGE-1 Well, Niger Delta Basin

This work focuses on subjecting ninety (90) sidewall core well samples to sedimentological and geochemical parameters to determine the lithologies and the geochemical ratios of the OGE-1 Well in the Niger Delta Basin. The sedimentological analysis with sample description yielded lithologies that are sand, shaly sand, sandy shale and shale. The sand lithologies ranged from fine to coarse grained, well sorted to poor sorted at different depths, while the shale lithologies ranged from light to dark coloured shales which is controlled by the organic matter content in the shale. This finally produced a lithologic frame work of the well. The result of the geochemical analysis led to the creation of the geochemical ratio of Na/Zn (0.739 \u2013 5.610) and K/Mn (21.170 \u2013 69.37) for 90 side wall core samples. Na and K had variations in their graphs showing intermittent alternating abundance downhole. Na and K being components of the weathering of feldspars are indicative of abundance of clay minerals. The variation of the Na/Zn and K/Mn profile indicates the alternate deposition of clay and sand size deposits giving the environment of deposition to be paralic

Palynological zonation and paleoclimatic condition of the sediments penetrated by Ash-3 well in the greater Ughelli Depobelt, Niger Delta Basin

Palynological zonation and paleoclimatic condition of the sediments penetrated by Ash-3 Well in the Greater Ughelli Depobelt, Niger Delta was carried out in order to determine the palynological biozonation, age and the paleoclimatic condition the sediments were formed. The palynological analysis was carried out on seventy (70) ditch cutting samples at different intervals between 15ft to 11,430ft which allowed the recovery of one thousand, three hundred and twelve (1312) palynomorphs that includes one thousand, one hundred and fifty (1150) miospores, eleven (11) dinocysts and one hundred and fifty one (151) ancillary microfossils. Five (5) palynological zones were established using palynological characteristic of the age diagnostic index markers. The palynological zones established were the lumped P650-P670, lumped P620-P630, P580, P560 and P540 Zones. The age of the sediments penetrated by the well using the age diagnostic markers range from Oligocene to Early Miocene epoch. Based on the dominance of Zonocostites ramonae over Monoporites annnulatus, it showed that the sediments were deposited in a predominantly humid climate, cooler and wetter climatic condition. Keywords: biozonation, depobelt, paleoclimatic, Agbada, diagnostic index marker

Foraminiferal biostratigraphy and paleoenvironmental analysis of the sediments penetrated by Sahaiawei-1 well in the Northern Delta Depobelt, Niger Delta Basin

Foraminifera biostratigraphy and paleoenvironmental analysis of the sediments penetrated by Sahaiawei-1 Well in the Northern Delta Depobelt, Niger Delta Basin was carried out in order to determine the foraminifera biozonation, age, paleobathymetry, depositional environment and paleo-oxygen condition of the well. The total foraminifera population recovered was two thousand, three hundred and sixty five (2365), with planktic foraminifera constituting one hundred and fifty four (154) forms, while calcareous benthic and agglutinated benthic foraminifera recovered accounted for two thousand, one hundred and sixty two (2162) and fourty nine (49) of the total foraminifera population respectively. The total foraminifera species recovered was fifty nine (59); planktic accounted for twenty (20) foraminifera species, while calcareous and agglutinated benthic foraminifera accounted for thirty one (31) and eight (8) foraminifera species respectively. Five benthic foramineferabiozones were identified: lumped P7-P13, P5-P6/P7, lumped P3-P4, lumped P1-P2 and M18 Zones of Blow (1969, 1979). The result of the analysis indicates that the entire analysed interval (1800ft – 10680ft) was deposited during the Late Maastrichtian to Late Eocene epoch. The depositional environments of the Well varied from littoral, marginal, shallow and deep marine environments. Keywords: Biozonation, Calcareous, Arenaceous, Agglutinated, Hyposaline Marshes, Hyposaline Shelf Se

Lithofacies characterization and quantitative mineralogical analysis of the sediments from Sahaiawei-1well in the northern Delta Depobelt of the Niger Delta Basin

The sediments of Sahaiawei-1 Well in the Northern Delta Depobelt are represented by sand and shale alternation. Lithofacies characterization and X-ray diffraction technique were used to characterize the sediments from the well in order to characterize the lithofacies, identify the minerals present, determine environment of deposition and identify potential zones for hydrocarbon exploitation. The lithofacies characterization was based on the textural properties, mineralogical composition, fossil content, homogeneity and heterogeneity of the lithofacies units of the well. The lithofacies analysis for Sahaiawei-1 Well identified four (4) lithofacies types of mainly sandstone, shaly sandstone, sandy shale and shale; and fourteen (14) lithofacies zones. The result of the X-ray diffraction analysis identified the following clay minerals – kaolinite, illite/muscovite, chlorite and sepiolite; carbonates and non-clay minerals. Therefore, due to the high percentage of kaolinite in Sahaiawei-1 Well (2% to 39.87%), it could be concluded that pore filing kaolinite may have more effect on the reservoir quality than the pore bridging illite and pore lining chlorite. Keywords: alternation, lithofacies, X-ray diffraction, reservoir, mineralog

Use of Sedimentological and Geochemical Parameters to Evaluate the Lithologies and Geochemical (Na/Zn and K/Mn) Ratios of OGE-1 Well, Niger Delta Basin

This work focuses on subjecting ninety (90) sidewall core well samples to sedimentological and geochemical parameters to determine the lithologies and the geochemical ratios of the OGE-1 Well in the Niger Delta Basin. The sedimentological analysis with sample description yielded lithologies that are sand, shaly sand, sandy shale and shale. The sand lithologies ranged from fine to coarse grained, well sorted to poor sorted at different depths, while the shale lithologies ranged from light to dark coloured shales which is controlled by the organic matter content in the shale. This finally produced a lithologic frame work of the well. The result of the geochemical analysis led to the creation of the geochemical ratio of Na/Zn (0.739 – 5.610) and K/Mn (21.170 – 69.37) for 90 side wall core samples. Na and K had variations in their graphs showing intermittent alternating abundance downhole. Na and K being components of the weathering of feldspars are indicative of abundance of clay minerals. The variation ofthe Na/Zn and K/Mn profile indicates the alternate deposition of clay and sand size deposits giving the environment of deposition to be paralic. Keywords: Chemo-stratigraphy, Paleo-environment, Sedimentological, Stratigraphy, Geochemistr