107Geological and Petrophysical Evaluation for an Oil Well


In this paper, a sequence stratigraphy and reservoir petrophysical analysis of a single oil well (Well H) has been prepared by using an available core data and wireline logging data with a view to characterizing the reservoir. In addition, petrophysical analysis initiated with lithology identification and lithological panels interpreted from well log data show that the study area is characterized by sand-shale interbedding. Moreover, appropriate logs have been used to interpret the reservoir for their fluid content, as are result; hydrocarbons versus water bearing zones were outlined. Furthermore, the reservoir interval generally presents vertical anisotropy and great heterogeneity with thick sand filled channel layers. The core involves mostly of red bed of sandstone with some structure- less which is deposited in fluvial environment system. However, the core data are relatively collated to wireline data to assess and survey the reservoir rock petrophysical properties. A hydrocarbon water contact (HWC) was obtained from 1655 m. In addition, an average of 78.5 m of gross rock was decomposed with a counted 17.35 m of net pay exhibit average values of 0.2832 for water saturation and 0.1785 for porosity.

Keywords: Formation Evaluation, Net-pay Reservoir, Gross Rock.



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