Sedimentology and Depositional Environment of Reservoir Sands of Kanga Oil Field Onshore Niger Delta

International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VI, Issue VIII, August 2021|ISSN 2454-6194

Sedimentology and Depositional Environment of Reservoir Sands of Kanga Oil Field Onshore Niger Delta

*Ideozu R.U. and Chiazor F.I.
Department of Geology, University of Port Harcourt,
*corresponding author

Abstract: In this study, reservoir sands from seven wells Kanga Oil field in the Onshore Niger Delta were analyzed sedimentologically to determine the level of spatial distribution of significant heterogeneity in the subsurface and infer the depositional environments. From the sedimentological analyses, three reservoir intervals J100, K100 and L100 of interest were identified based on the gross thickness of the reservoir sand, cleanliness of the reservoir sand and presence of hydrocarbon, and correlated across the field using suites of wire line logs. The environment of deposition was interpreted using gamma-ray log motif and lithologic description from Sidewall samples. The environments of deposition have been interpreted as Channel sands, Upper Shoreface, Lower Shoreface and Marine Shale, a reflection that the sediments was deposited in medium to low energy environment which favors the deposition of fine to medium grains sediments

Key words: sedimentology, depositional environment, reservoir, lithologic and hydrocarbon

I. INTRODUCTION

Petroleum resides in the tiny pore spaces and open fractures of reservoir sands (Schlumberger, 1989). To find them, a detailed sedimentological and petrophysical analysis is needed to guide production and well placements, well paths for optimal hydrocarbon recovery. The key process controlling variation in stratal patterns and facies distribution is accommodation and sedimentation supply. Accommodation is created by a combination of tectonics and sea level fluctuations while the filling of the basin is a product of sediment supply, influenced by the combined effects of basin geometry, physiography, provenance, and climate. ). Studying the spatial variability of saturating reservoir fluids (hydrocarbon) is a significant aspect of oil and gas production.
The paper is seeks to establish relationships between reservoir properties with various depositional environments within the Onshore Niger Delta through a detailed sedimentological study.
Geology of The Niger Delta Basin
The Niger Delta as a prograding sedimentary complex which evolved from the separation of the African and South American continental plates. The origin of the Niger Delta is believed to have began after the development of the RRR (ridge-ridge-ridge) system. The failed arm of this triple structure is the Anambra-Benue rift valley within which the oceanic crust was inactive. The rivers depositional centers moved seawards thus making the coastal plain deposits to become progressively younger in that direction (Burke, 1971; Wright, 1976).

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