PETROPHYSICAL ANALYSIS OF NUBIAN RESERVOIR, RIMAL OIL FIELD-SIRTE BASIN

Sadeg H. El-Bakush; Haithem A. Minas

doi:10.66411/jer.v9i9.164

Authors

Sadeg H. El-Bakush Geological Engineering Department, Faculty of Engineering, Al Fateh University, Tripoli, Libya, Author
Haithem A. Minas Earth and Environmental Science Department, Faculty of Science, Al Marqab University, Al Khums, Libya, P.O. Box 40127 Author

DOI:

https://doi.org/10.66411/jer.v9i9.164

Keywords:

Petrophysical, Water saturation, Net pay thickness, Hydrocarbon pore volume, Initial oil in-place and original oil in-place, Secondary porosity

Abstract

The Nubian Formation has been divided into three zones, upper Nubian, varicolored shale and lower Nubian. Structurally, the Rimal oil field is an elongated ridge bounded by two main faults running northwest southeast.

Petrophysical characteristics and fluid reserves of the studied Nubian Formation have been examined in detail according to a complete package of spontaneous-potential resistivity, gamma ray, neutron, sonic, and density logs selected from 12 wells drilled in Rimal oil field. This field is produced from the lower and upper Nubian reservoir sandstones (Early Cretaceous). An average value of total porosity was estimated as 16% from the lower reservoir and 18% for the upper reservoir. Water saturation is 25% for lower reservoir and 30% for upper reservoir. The hydrocarbon pore volume is 50 feet for lower, and 45 feet for upper reservoir and maximum net pay of the lower reservoir reaches up to 400 feet and 300 feet in upper reservoir. The total original oil in place, initial oil in place and recoverable oil are 97.89 MM barrels, 59.32 MM barrels and 27.54 MM barrels respectively.

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