PowerPoint Presentation

University of Ibadan, NigeriaAdvisorDr. O. A EhinolaTeam Members:

2013 NAPE/AAPGBasin Evaluation Competition

RESERVOIR CHARACTERIZATION, SWEET SPOT MAPPING AND ECONOMIC VIABILITY OF UI NAPE OIL FIELD BEC 2013

TOPIC:

Fault traps

Combination Traps4-way dip closure

2 Petroleum System:OA Shale-Tomiwa Sst Petroleum SystemChallenge Shale-Agbowo Sst Petroleum System

3 New Prospects

2 Drillable SitesEXECUTIVE SUMMARY3 Types of Play:

Seismic Survey (3D Seismic) With seven(7) Well data of which only three(3) were within the survey area.Wells Data: (logs & Reports) 21_10-2 (Oil Well)21_10-1 (Oil Well)21_10-5 (Oil Well)21_10-3a(Undefined)21_10-4 (Dry)21_10-6 (Dry)21_10-8 (Oil)

Data Set

= Oil well

= Undefined

= Dry

Well logcorrelationDepthConversionSequence Strat.& DepositionalEnvironment

Burial History/1 D Basin Model

Traps, Formation EvaluationProspect EvaluationRisk Assessment & Volumetric AnalysisFinal RecommendationFor Business ActionWORK FLOWPetrophysical InterpretationSeismicInterpretationWell tie AnalysisGeodynamicsStructural InterpSource & SealPresence, andQuality EvaluationReservoir Presence& Quality Evaluation

Basic Technical InterpretationSeismic InterpretatonWell Log Interpretation

6

Original Seismic SectionEnhanced Seismic SectionSeismic Section Without Interpretation

Zone of extensional Tectonism

Post-Tectonic Deposition

The Overlying sequence affected by Extensional forces which led to the Faulting Patterns Geodynamics & Tectonic Settings

Geodynamics is the application of geophysical principles in understanding the dynamics (movement) of the earth and the effect of such movement on the earth

Direction of Extentional forcesTectonic Habitat: Extensional Tectonic HabitatCrest of the Anticline, a result of the Tectonism

Basin classification: Rifted Basin systemSyntectonic or Pre-tectonic depositon????

Crest of the AnticlineUplift Boundary Limbs of the AnticlineVariance Time Slice of Z Showing an Uplift Resulting in the Formation of an Anticline

Crest of the Anticline, a result of the Uplift

Variance Time Slice of Z Showing a flat Horizon

Seismic Interpretation Horizon &fault interpretationSynthetic seismogram & well to seismic tie

Composite seismic section displaying synthetic seismogram and well tops derived from composite well logPosition of the oil wells relative to the anticlinal structureComposite seismic line joining the 3 oil wells on a 2D windowNWSENW

TWT MapDepth Map

Time-Depth Relationship

Top GG SstTop Agbowo SstBase GG SstBase Agbowo SstTop Tomiwa SstBase Tomiwa SstDepth Structural MapsCrest of Anticline

IL 13021 showing Antithetic and Synthetic faults which may be related to extensional movement

STRUCTURAL FEATURESf1f8f9f7f5f4f2f3f6Structural Interpretation MAJOR FAULTSMINOR FAULTS

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=

Fault Interpretation

GG SSt Oremeji ShaleAgbowo SStChallenge ShaleTomiwa SSt OA ShaleCarbonate Reef /Salt DiapirOldestYoungestTop GG SstTop Agbowo SstBase GG SstBase Agbowo SstTop Tomiwa SstBase Tomiwa Sst

Zone of extensional Tectonism

Post-Tectonic Deposition

The Overlying sequence affected by Extensional forces which led to the Faulting Patterns Seismic StratigraphyCrest of the Anticline, a result of tectonic Rifting

1

2

3

21- Parallel, continuous, high amplitude seismic facie.2- Chaotic, discontinuous, low amplitude seismic facie.3- Semi parallel, continuous, high amplitude seismic facie.Seismic Facies

3

Sweet Spot Mapping

This is a type of DHI tool which involves using the sweetness attribute of the seismic volume to indicate possible zones of hydrocarbon generation within a reservoir

Sweet Spots

Basic Technical InterpretationSeismic InterpretatonWell Log Interpretation

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Well Log CorrelationTop GG SstTop Agbowo SstBase GG SstBase Agbowo SstTop Tomiwa SstBase Tomiwa Sst

RESERVOIR 1RESERVOIR 3RESERVOIR 2

Log interpretation & Sequence Stratigraphy

HST : High-stand system tractTST : Transgressive system tractLST : Low-stand system tractMFS: Max. flooding surfaceTS: Transgressive surfaceSB: Sequence boundary

Depositional Environment Settings

21

Coarse GrainFine to Medium GrainVery Fine GrainGrain size plot for the investigated sands in the studied wells (After Asquith and Gibson, 1982)

EASTWESTDirection of sediment deposition

Agbowo SStTomiwa SSt GG SSt

GG SSt Agbowo SStTomiwa SSt Well Section showing ReservoirsSeismic Section showing Reservoirs

AGBOWO

Thickness MapsGG Sst (Reservior 1)Tomiwa Sst (Reservior 3)Agbowo Sst (Reservior 2)

25SandsTop (MD)Bottom (MD)Gross thickness mThickness (Net Pay)mNTG(%)Av.Net Porosity (%)Av.Water Saturation (%)Av.Bulk water VolumePermeability(md)Sh (%)FVsh(%)Swirr(%)GG Sst1306.771831.31524.54443.3784.6535.37422795.7915.355.38Agbowo Sst2179.182278.3199.1374.0574.722.551.330.11108948.6715.3225.38.75Tomiwa Sst2519.912669149.09144.5396.9417.7675.40.1315424.625.473.0611.28

SandsTop (MD)Bottom (MD)Gross thickness mThickness (Net Pay)mNTG(%)Av.Net Porosity (%)Av.Water Saturation (%)Av.Bulk water VolumePermeability(md)Sh (%)FVsh(%)Swirr(%)GG Sst1470.12106.2636.164490.0434.48343426.129.965.53Agbowo Sst2249.232479.85230.6222922.1520.596.840.224963.1618.7122.159.67Tomiwa Sst2580.632653.372.6788.7687.2617.549.880.0913624.626.2912.7411.47

SandsTop (MD)Bottom (MD)Gross thickness mThickness (Net Pay)mNTG(%)Av.Net Porosity (%)Av.Water Saturation (%)Av.Bulk water VolumePermeability(md)Sh (%)FVsh(%)Swirr(%)GG Sst1989.942055.5465.683.4181.9134.37340586.1618.095.55Agbowo Sst2227.592274.246.6146.1279.7523.550.720.14543949.2813.9520.258.35Tomiwa Sst234118.521523.3310.8

Log interpretation & Formation Evaluation

Well 21-10_1Well 21-10_2Well 21-10_542279343423405835.3734.4834.3722.520.523.517.7617.518.596.9422.1511.288.755.385.539.6711.475.558.3510.8

Agbowo SStTomiwa SSt Porosity chart of Agbowo Sst and Tomiwa Sst across the 3 wells

Permeability chart of Agbowo Sst and Tomiwa Sst across the 3 wells

Petrophysical Modelling

Volume of ShaleReservior 2 (Agbowo Sst)

NTGReservior 2 (Agbowo Sst)

PorosityReservior 2 (Agbowo Sst)21_10_121_10_221_10_5

Petroleum System Analysis

After Passey et al (1990)Schematic of log R Response

Source and Seal Distribution

TOC Evaluation from logSchmoker and Hesters equation (1983)

Schmoker and Hesters equation (1983)Visualization of Play system on well logs

Burial History

Basin Modeling

Critical Point of Hydrocarbon generation

Variation in Porosity with Lithology and depthMaturity trend of OA Shale with Geologic timeTemperature Model of OA Shale, showing changes in Temp with time

Trap Analysis and Prospect Evaluation

2-way Dip (Fault Dependent) ClosureStratigraphic Traps

d

d

d

Hydrocarbon AccumulationsSecondary MigrationPrimary Migration

sealTrapping and Migration Mechanisms

Petroleum SystemsFault Traps 4-way dip Closure Combination TrapsChallenge Shale-Agbowo SSt Petroleum SystemOA Shale-Tomiwa SSt Petroleum System

Trapping MechanismTwo Petroleum Systems will be discussed

Challenge Shale-Agbowo Sandstone Petroleum System

Composite Log of Agbowo Sst from 21_10-2Source rock: Challenge ShaleReservoir: Agbowo SstSeal: Oremeji Shale

AA

OA Shale-Tomiwa Sst Petroleum System

Source Rock: OA ShaleReservoir: Tomiwa SstSeal: Basal part of Challenge ShaleComposite Log of Tomiwa Sst from 21_10-2

Top Tomiwa SstBase Tomiwa Sst

POSSource and MigrationSealReservoirTrapAgbowo Sst0.910.911RISK

Prospect 1Prospect Evaluation

1

Top Agbowo Sst

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POSSource and MigrationSealReservoirTrapAgbowo Sst0.7210.910.8RISK

Prospect 2Prospect Evaluation

2

1

2Top Agbowo Sst

41

POSSource and MigrationSealReservoirTrapTomiwa SST0.910.911RISK

Prospect 3

3

42

PW1PW2Drillable Wells Proposed

PW2

Top Agbowo Sst Top Tomiwa Sst

Volumetrics Analysis

RiskCalculation

Play Success * Prospect Success = Prospect Chance45Reservoir Quality*Source Rock Quality*Source Rock Maturity*Migration Route*Timing of Charge*Trap Integrity=Prospect SuccessReservoir Presence*Source Presence*Seal Presence=Play SuccessRisk Assessment and Volumetrics

Prospect ChanceProspect SuccessProspect EvaluationPlay successPlay EvaluationProspect Name TrapIntegrityTime ChargeMig RouteSO M SO QR QS PSO PR P0.720.7211110.90.8111110.640.6411110.80.8111120.80.8111110.811113

RP = Reservoir PresenceSOP = Source PresenceSP = Seal PresenceRQ = Reservoir QualitySOQ = Source QualitySOM = Source Maturity

VariableMinimum (P10) Most Likely(P50) Maximum(P90) Formation Net Pay(m)36.78 74.05179.54 Agbowo SSt (PROSPECT 1) Porosity(%)20.522.523.5 FVF1.251.31.35 HC Saturation (%)3.1648.6749.28 Recovery Factor(%)101520 Area(Km2)56.579945.064551.2671 OIIP(Km3)0.0107846190.281099530.78959568 RR(Km3)0.0010784620.042164920.15791913 RR(MBO)(Unrisked)6.78352572265.2174993.311 RR(MBO)Risked@65%4.40929172.39131645.65215 Tomiwa SSt Net Pay(m)4563.22143.12 Porosity(%)1517.517.76 FVF1.0781.0821.09 HC Saturation (%)24.63150.12 Recovery Factor101520 Area(Km2)35.553441.3177751.67 OIIP(Km3)0.05476470.13096750.60390178 RR(Km3)0.005476470.0196451250.120780356 RR(MBO)(Unrisked)34.4469963123.5678363759.7084 RR(MBO) Risked @70%24.1128974186.49748541531.79588

Volumetrics Estimation Agbowo Sst (PROSPECT 2) Net Pay(m)4563.22143.1 Porosity(%)1517.517.76 FVF1.0781.0821.09 HC Saturation (%)24.63150.12 Recovery Factor(%)101520 Area(Km2)5.0089285.0089285.008928 OIIP(Km3)0.00771550.0158771210.058534504 RR(Km3)0.000771550.02381560.0117069 RR(MBO)(Unrisked)4.853049514.9800639373.636407 RR(MBO)Risked@65%3.882439611.9840511458.90912563

No of successPOS @72%POS @64%POS @80%00.0000110.00100.000005110.000240.00160.00001820.00250.0120.0002930.0150.0480.002840.0580.1300.01750.1490.2300.06660.2570.2670.1870.2830.20520.3080.1820.0910.3090.0520.0180.13

Table showing the number of successful wells drilled with their respective probabilities as estimated from the binomial equation (p + d)n .(According to McCray 1975)

@64@72@80

GRAPHS OF THE BINOMIAL DISTRIBUTION

GRAPH OF THE BINOMIAL DISTRIBUTION FOR GAMBLERS RUIN

Number of wildcatsProbability of Drilling Dry Holes Probability of two or more discoveries Number of wildcatsProbability of three or more discoveries Probability of one or more discoveries Number of wildcatsNumber of wildcats

Graph of the binomial distribution for gamblers ruin or no discovery for six success rationsGraph of the binomial distribution for one or more discoveries

Graph of the binomial distribution for three or more discoveries

Drillable Wells Proposed

W2

W2W1

Drillable Wells Proposed

Position of Proposed Well 2W2

Composite lineNWSEW2

W1Position of Proposed Well 1NWSEDrillable Wells Proposed W1

Seismic Survey (3D Seismic) With seven(7) Well data of which only three(3) were within the survey area.Wells Data: (logs & Reports) 21_10-2 (Oil Well)21_10-1 (Oil Well)21_10-5 (Oil Well)21_10-3a(Undefined)21_10-4 (Dry)21_10-6 (Dry)21_10-8 (Oil)

Drillable well proposed on Base map

= Oil well

= Undefined

= Dry

= ProposedPW2PW1

RECOMMENDATIONS

Well 21_10_5 should be drilled deeper

The location of the area and Geochemical data are needed to further prove our prospect.

More wells should be made available especially on the survey area (Eastern part) in order to have more control on the survey area.Availability of core samples and outcrop samples would enhanced better understanding and interpretation of the area.

UI BEC TEAMAPPRECIATES

The AdvisorDr. O. A. Ehinola

INDUSTRY MENTORS

NAPE Prof M. N. TijaniThe Head of Geology Department University of Ibadan

Any Question