Lithofacies and Depositional Environment from Geophysical Logs of EMK Field, Deepwater Niger Delta, Nigeria

Abstract

The lithofacies and environments of deposition of the EMK field, in parts of the deepwater zone of Niger Delta Basin, have been carried out. Geophysical well logs from two deep oil wells were used. Shale and sand were identified in the gamma ray logs. The shale lithology is more dominant than the sand and this was interpreted as the marine Akata Formation. Four sand bodies were identified and correlated across the wells. The shapes of the gamma ray signatures are funnel, bell and cylindrical. Prograding, retrograding and aggradational parasequences were identified from the stacking patterns of the gamma ray curves. The environments of deposition delineated for the study area are slope fans and basin floor fans.

Turbidite Dynamics and Hydrocarbon Reservoir Formation in the Tano Basin: A Coastal West African Perspective

“…Further studies have examined facies, netto-gross ratios, clay volume, porosity, and permeability based on core data, modeling stacked turbidite channels in Angola and identifying collapse margin deposits as primary barriers to permeability [14]. Gamma ray logs have also been used to identify and characterize sand bodies in the EMK field within the Niger Delta region, while seismic reflection data has been used to investigate subsurface fluid flow features and their correlation with hydrocarbon systems in Egypt's Alamein basin [15] [16] [17] [18]. Other studies have focused on characterizing reservoirs in different regions, including fluvial reservoirs in the Laohekou Oilfield, China, fluvial channel systems and gas sand reservoirs in Australia's Carnarvon Basin, and submarine channels and valleys in the eastern Mediterranean Sea [19] [20] [21].…”