Browsing by Author "Chatterjee, Tapas K."

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    Geochemistry and weathering history of the Balfour sandstone formation, Karoo basin, South Africa: Insight to provenance and tectonic setting
    (Elsevier, 2018) Oghenekome, Monica E.; Chatterjee, Tapas K.; van Bever Donker, Jan M.; Hammond, Napoleon Q.
    Geochemical analysis on sandstones from clastic sediments was carried out to understand the tectonic setting and subsequent post-depositional change in the Karoo basinal fill of the fluvial deposits of the Balfour Formation during the Late Permian to Early Triassic period. The major and trace element analysis reveal a relatively homogeneous provenance for the sandstones. The geochemical analysis shows that these rocks are first order mature sediments, derived from igneous and/or meta-igneous rocks of a felsic composition. The results show that the sandstone consists of SiO2 (71.58 wt. %), followed by Al2O3 (14.48 wt. %), but with low contents of Fe2O3+MgO (4.09 wt. %) and TiO2 (0.47 wt. %). These sandstones are classified as litharenites and arkoses based on the elements constituent ratio of various schemed adopted. The sandstone in the provenance discrimination diagram plots in the dissected and transitional arc fields suggesting an active margin and continental island arc provenance, preserving the signature of a recycled provenance. The Chemical Index of Alteration (CIA) ranging from 63.56 to 67.10% suggests recycling processes, and that the source area has undergone a moderate degree of chemical weathering. The geochemical characteristics of the sediment suggest the source area of uplifted terrane of folded and faulted strata with detritus of sedimentary and metasedimentary origin.
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    An integrated study of the early cretaceous (Valanginian) reservoir from the Gamtoos Basin, offshore South Africa with special reference to seismic cacies, formation evaluation and static reservoir modeling
    (University of the Western Cape, 2019) Ayodele, Oluwatoyin; Chatterjee, Tapas K.; van Bever Donker, Jan
    Integrated approaches in the study of petroleum exploration are increasingly becoming significant in recent times and have yielded much better result as oil exploration is a combination of different related topics. The production capacity in hydrocarbon exploration has been the major concern for oil and gas industries. In the present work an integrated approach was made with seismic, well logs and biostratigraphy for predicting the depositional environment and to understand the heterogeneity within the reservoirs belonging to Valanginian (Early Cretaceous) age of Gamtoos Basin, Offshore South Africa. Objectively, the integrated work was mainly based on seismic stratigraphy (seismic sequence and seismic facie analysis) for interpretation of the depositional environments with combination of microfossil biostratigraphic inputs. The biostratigraphic study provides evidences of paleo depth from benthic foraminifera and information about bottom condition within the sedimentary basin, changing of depositional depth during gradual basinal fill during the Valanginian time. The petrophysical characterization of the reservoir succession was based on formation evaluation studies using well logs to investigate the hydrocarbon potential of the reservoir across Valanginian depositional sequence. Further, the static modeling from 2D-seismic data interpreted to a geological map to 3D-numerical modeling by stochastic model to quantify the evaluation of uncertainty for accurate characterisation of the reservoir sandstones and to provide better understanding of the spatial distribution of the discrete and continuous Petrophysical properties within the study area.
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    An integrated study of the early cretaceous (Valanginian) reservoir from the Gamtoos Basin, offshore South Africa with special reference to seismic facies, formation evaluation and static reservoir modeling
    (University of the Western Cape, 2019) Lasisi, Ayodele Oluwatoyin; Chatterjee, Tapas K.
    Integrated approaches in the study of petroleum exploration are increasingly becoming significant in recent times and have yielded much better result as oil exploration is a combination of different related topics. The production capacity in hydrocarbon exploration has been the major concern for oil and gas industries. In the present work an integrated approach was made with seismic, well logs and biostratigraphy for predicting the depositional environment and to understand the heterogeneity within the reservoirs belonging to Valanginian (Early Cretaceous) age of Gamtoos Basin, Offshore South Africa. Objectively, the integrated work was mainly based on seismic stratigraphy (seismic sequence and seismic facie analysis) for interpretation of the depositional environments with combination of microfossil biostratigraphic inputs. The biostratigraphic study provides evidences of paleo depth from benthic foraminifera and information about bottom condition within the sedimentary basin, changing of depositional depth during gradual basinal fill during the Valanginian time. The petrophysical characterization of the reservoir succession was based on formation evaluation studies using well logs to investigate the hydrocarbon potential of the reservoir across Valanginian depositional sequence. Further, the static modeling from 2D-seismic data interpreted to a geological map to 3D-numerical modeling by stochastic model to quantify the evaluation of uncertainty for accurate characterisation of the reservoir sandstones and to provide better understanding of the spatial distribution of the discrete and continuous Petrophysical properties within the study area.