This document summarizes a student's industrial work experience project at Pan Ocean Oil Corporation. The student analyzed well logs from the Ona 5 well to evaluate two hydrocarbon-bearing formations - the F3 sand and L sand. For each formation, the student calculated parameters like thickness, porosity, water resistivity, water saturation, and hydrocarbon saturation. The analysis found that both formations had over 50% water saturation, indicating care would need to be taken to avoid coning during production.

1. A PRESENTATION
On
STUDENT INDUSTRIAL WORK EXPERIENCE
SCHEME
UNDERTAKEN IN
PAN OCEAN OIL CORPORATION
BY
DADA, TAIWO OLALEKAN

2. Introduction
Aims & Objectives of SIWES
• To provide opportunity to apply acquired knowledge in actual practice.
• To expose students to the latest developments, information, techniques and
equipment which may not be available within the academic institutions.
• To assist students to transit from an academic setting to a working
environment and to enhance students potential for later job opportunities.
• To reduce the incoherence between theoretical learning and practical work.
• To provide the avenue for students of higher to acquire skills and experience
in both the theoretical and practical aspects in their respective course of
study

3. Geology of Niger Delta
• Benin Formation
• Agbada Formation
• Akata Formation

5. PETROPHYSICAL INTERPRETATION OF
WELL LOGS
TYPES OF LOGGING
• LOGGING WHILE DRILLING (LWD)
• WIRELINE LOGGING (WL)
• MUD LOGGING (ML)

6. Example of Wireline Logging

7. Types of Wireline Logging
• Open hole Logging
• Cased hole Logging

8. PRINCIPAL USES OF WIRELINE LOGS
• Lithology Identification
• Porosity.
• Permeability.
• Shale Volume.
• Formation water salinity.
• Hydrocarbon Saturation.
• Gas Identification.

9. LOG TYPES
• GAMMA RAY LOG
• RESISTIVITY LOG
• NEUTRON LOG
• DENSITY LOG

10. FORMATION EVALUATION, ANALYSIS, AND INTERPRETATION OF ONA 5
• The objective of this exercise is to determine the reservoirs,
Vshale, NTG, Porosity and Water Saturation.
• Petrophysical evaluation of Ona 5 was carried out using
Gamma log, Resistivity log, neutron log and density log.
• I worked on two hydrocarbon bearing sands which are the F3
and L sands.

11. CALCULATION OF RESERVIOR
THICKNESS FOR F3 SAND
• Top of Reservoir=11193feet
• Bottom of Reservoir=11217feet
• Gross thickness=24feet
• Net Sand=18feet
• N/G=0.9

12. Figure showing F3 Sand of Ona 5

13. CALCULATION OF POROSITY FOR F3
SAND
Ф = (ðma - ðb)/ (ðma - ðfl)
Where,
ðma = Matrix density (2.65g/cc)
ðb = Bulk density (this is obtained from the
log)
ðfl = Fluid density (taken as 1g/cc)

14. CALCULATION OF WATER RESISTIVITY
FOR F3 SAND
• Rw = Rtϕm
• Rw = water Resistivity
• Rt = True Resistivity (Resistivity deep)
• Φ = Porosity
• m = Cementation factor
• Top = 11193 Bottom = 11217
• ϕRw = (2.65-2.30/2.65-1) = 0.21
• Rw = 1.8*(0.21) = 0.09

15. Water Resistivity Interval

16. COMPUTATION OF WATER
SATURATION (SW) FOR F3 SAND
Sw = n√ (a.Rw/ Фm.Rt)………Archie Equation
Where,
Rt = Deep Resistivity from log
Rw = Down hole water resistivity (read from log, value
was taken as 0.2)
Ф = Effective porosity
m = unique property of the rock, (usually a constant
taken as 1.6)
a = unique property of the rock, (constant taken as 1)
n = Saturation exponent (taken as 2).

17. CALCULATION OF HYDROCARBON
SATURATION FOR F3 SAND
HC_Sat = 1-Sw
Where;
HC_Sat = Hydrocarbon saturation
Sw = Water Saturation

18. Top Bottom Thickness(H) GR Rt_d Density Fluid_D Phi(φ) Phi*H Rw Sw HC_Sat HC_Sat*H Sw*Phi*H HC_Sat*Phi*H
11193 11195 2 90 13 2.45 0.8 0.1 0.2 0.09 0.8 0.2 0.4 0.16 0.04
11195 11198 3 95 12 2.43 0.8 0.11 0.33 0.09 0.8 0.2 0.6 0.264 0.066
11198 11201 3 68 16 2.45 0.8 0.1 0.3 0.09 0.75 0.25 0.75 0.225 0.075
11201 11202 1 82 15 2.45 0.8 0.1 0.1 0.09 0.77 0.23 0.23 0.077 0.023
11202 11203 1 76 11 2.39 0.8 0.14 0.14 0.09 0.9 0.1 0.1 0.126 0.014
11203 11205 2 75 14 2.42 0.8 0.12 0.24 0.09 0.8 0.2 0.4 0.192 0.048
11205 11206 1 82.5 9 2.39 1 0.15 0.15 0.09 0.5 0.5 0.5 0.075 0.075
11206 11210 4 100 7 2.37 0.8 0.15 0.6 0.09 0.6 0.4 1.6 0.36 0.24
11210 11215 5 60 40 2.51 0.8 0.075 0.375 0.09 0.5 0.5 2.5 0.1875 0.1875
11215 11217 2 105 9 2.37 1 0.16 0.32 0.09 0.5 0.5 1.0 0.16 0.16
24 2.755 1.8265 0.9285
Table showing calculated value parameters for F3 Sand

19. F3 sand
• CALCULATION OF AVERAGE POROSITY
Average Phi(ϕ) = Sum(Phi*H)/Sum(H)
= 2.755/24
= 0.114
• CALCULATION OF WATER SATURATION
Average Sw = Sum(Sw*Phi*H)/Sum(Phi*H)
= 1.8265/2.755
= 0.66
• CALCULATION OF HYDROCARBON SATURATION
Average HC_Sat = Sum(HC_Sat*Phi*H)/Sum(Phi*H)
= 0.9285/2.755
= 0.337

20. Figure showing L Sand of Ano 5

21. Top Bottom Thickness(H) GR Rt_d Density Fluid_D Phi(φ) Phi*H Rw Sw HC_Sat HC_Sat*H Sw*Phi*H HC_Sat*Phi*H
12718 12722 4 99 6 2.21 0.6 0.21 0.85 0.2 0.6 0.4 0.8 0.51 0.34
12722 12732 10 84 5.5 2.24 0.6 0.2 2 0.2 0.8 0.2 2 1.6 0.4
12732 12737 5 60 9 2.19 0.6 0.22 1.12 0.2 0.6 0.4 2 0.672 0.448
12737 12746 9 70 9 2.2 0.6 0.219 1.97 0.2 0.6 0.4 3.6 1.182 0.788
12746 12753 7 67.5 21 2.2 0.6 0.219 1.53 0.2 0.4 0.6 4.2 0.612 0.918
12753 12760 7 58 10 2.2 0.6 0.219 1.53 0.2 0.6 0.4 2.8 0.918 0.612
12760 12766 6 57 12 2.17 0.6 0.2 1.31 0.2 0.5 0.5 3 0.65 0.655
48 10.31 6.144 4.161
Table showing calculated value parameters for L Sand

22. L SAND
• CALCULATION OF AVERAGE POROSITY
Average Phi(ϕ) = Sum(Phi*H)/Sum(H)
= 10.31/48
= 0.21
• CALCULATION OF AVERAGE WATER SATURATION
Average Sw = Sum(Sw*Phi*H)/Sum(Phi*H)
= 6.144/10.31
= 0.59
• CALCULATION OF AVERAGE HYDROCARBON SATURATION
Average HC_Sat = Sum(HC_Sat*Phi*H)/Sum(Phi*H)
= 4.161/10.31
= 0.40

23. CONCLUSION
• It was observed that the two reservoirs have
more than 50% water saturation thus care
should be taken to avoid coning if
hydrocarbon is to be produced.