A PRESENTATION

On

STUDENT INDUSTRIAL WORK EXPERIENCE SCHEME

  UNDERTAKEN IN

PAN OCEAN OIL CORPORATION

BY 

DADA, TAIWO OLALEKAN

IntroductionAims & 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

Geology of Niger Delta

• Benin Formation• Agbada Formation• Akata Formation

PETROPHYSICAL INTERPRETATION OF WELL LOGS

TYPES OF LOGGING• LOGGING WHILE DRILLING (LWD)• WIRELINE LOGGING (WL)• MUD LOGGING (ML)

Example of Wireline Logging

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

PRINCIPAL USES OF WIRELINE LOGS

• Lithology Identification• Porosity.• Permeability.• Shale Volume.• Formation water salinity.• Hydrocarbon Saturation.• Gas Identification.

LOG TYPES

• GAMMA RAY LOG• RESISTIVITY LOG• NEUTRON LOG• DENSITY LOG

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.

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

Figure showing F3 Sand of Ona 5

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)

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

Water Resistivity Interval

COMPUTATION OF WATER SATURATION (SW) FOR F3 SAND

Sw = n√ (a.Rw/ Фm.Rt)………Archie EquationWhere,

Rt = Deep Resistivity from logRw = Down hole water resistivity (read from log, value was taken as 0.2)Ф = Effective porositym = 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).

CALCULATION OF HYDROCARBON SATURATION FOR F3 SAND

HC_Sat = 1-SwWhere;HC_Sat = Hydrocarbon saturationSw = Water Saturation

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

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

Figure showing L Sand of Ano 5

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

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

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.