Zubin Jehangir, Kevin Ashton, Peter Henderson, Laura Armstrong

Jasmine Reservoir Modelling and History Match

May 9, 2017 DEVEX 2017

Agenda

• Jasmine Field Introduction

• Post Production Data Acquisition

• Reservoir Modelling and History Match

• Opportunities & Future Potential

• Conclusions

May 9, 20172 DEVEX 2017

Introduction: Jasmine Location & Stratigraphy

Jasmine Field

• Partners: Shell & ENI

• High Pressure (11,500 psi)

• High Temperature (330 degF)

May 9, 20173

Joanne SandstoneInterbedded

Fluvial Continental Sands

Primary Reservoir

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Jasmine Discovered 2006Production 2013

Judy Discovered 1985Production 1995

Jade Discovered 1996Production 2001

Top Joanne Sand Depth (Triassic)

History & Production

Field History

• Discovered 2006

• Appraised 2007-2008

• Drilled 6 Development wells 2011-2013

• OBN 3D Seismic 2011

• First Production 19th Nov 2013

• Infill Drilling 2014-2015 (2 wells)

• Well Intervention 2016

May 9, 20174

Nov-13 Nov-14 Nov-15 Nov-16

Mb

oe

/d

Jasmine Field Production

All Wells

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Top Joanne Sandstone Depth(Contour Interval = 100 ft)

0 0.5km

Field Challenges

• Large hydrocarbon column (~2000 ft) with a low Kv/Kh ratio

• Strong differential depletion

• Restricted lateral connectivity

• Loss of reservoir quality with depth and column height

• Complex PVT with compositional gradient

• Oil-wet system/Complex rel-perm

• High near wellbore productivity

• Structural complexity (seismic and sub-seismic scale faults)

May 9, 20175

13750

14000

14250

14500

14750

15000

15250

15500

1000 3000 5000 7000

Dep

th T

VD

SS (

ft)

GOR (Scf/stb) & Psat (Psia)

Jasmine GOR and Psat vs Depth

GOR PSAT

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Perm

Low

er J

oan

ne

Post Production Data Acquisition

Received support and funding for extensive data acquisition

• PLT data acquisition showed better than anticipated productivity throughout the Joanne Sandstone• Lower Joanne had better flow characteristics than initial

anticipated based on logs and initial 3D models

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Red lines to right of well indicate cumulative PLT production

A’

A

-13000’

-16000’

A A’

HWC

-14000’blocked

Pentland

-15000’shallow TD

Josephine

Joanne

2016 PLT

Restriction

Restriction

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Reservoir Modelling Pre-Production

• Lower Joanne originally modelled using consistently sized channel bodies throughout, with a rock-type model• This, in conjunction with degrading rock

quality at depth, severely impaired modelled deep contribution

• Model required ten-fold increase in permeability to match actual PLT

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15,200

15,400

15,600

15,800

16,000

16,200

16,400

16,600

16,800

0% 20% 40% 60% 80% 100%

MD

ft

Cumulative Flow %

Well PLT Response

Actual PLT Data

Previous ModelPLT match

Well 1

Not to Scale

New History Match Model

• New model has more sheet like bodies in Lower Joanne

• Updated model is able to match PLT

• Connectivity in the deep layers is the key to matching the PLT’s

May 9, 20178 DEVEX 2017

15,200

15,400

15,600

15,800

16,000

16,200

16,400

16,600

16,800

0% 20% 40% 60% 80% 100%

MD

ft

Cumulative Flow %

Well PLT Response

Actual PLT Data

Updated ModelPLT Match

Well 1

Not to Scale

Geo model

Simulation

History Match Iterative process to

create history match

Nov-13 May-14 Dec-14 Jun-15 Jan-16 Jul-16

BO

PD

Jasmine Oil Production

HM Model End 2015

History Data End 2015

2016 ACTUALs

Current History Match to Production

• Model is run on gas rate control

• It can effectively predict overall GOR trend and post shutdown flush production

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Flush Production

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Nov-13 May-14 Dec-14 Jun-15 Jan-16 Jul-16

MM

SCF/

D

Jasmine Gas Production HM Model End 2015

History Data End 2015

2016 ACTUALs

Well Intervention Opportunity Example

• Interpretation of the PLT of one of the wells showed a blockage, with no production from the lower Joanne (~50% of 1800 ft column)

• This led to a coiled-tubing intervention to clean out the blockage and reperforate the section

• Result was significant additional production and well EUR

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• Without proving the lower Joanne had such potential, these well intervention activities would be difficult to justify

Post-Cleanout Performance

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0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0

5

10

15

20

25

30

35

40

Jun/16 Jul/16 Sep/16 Oct/16 Dec/16 Feb/17 Mar/17

Oil

Rat

e (B

bls

/d)

Gas

Rat

e (M

Msc

f/d

)

SEPARATOR RATES

Pre-Cleanout Performance

Post-Cleanout Performance

0

5000

10000

15000

20000

25000

Jun/16 Sep/16 Dec/16 Mar/17G

OR

(sc

f/st

b)

GOR

A’A

Remaining infill well potential on flank

Remaining infill well potential towards north

Future Opportunities

• Further well intervention opportunities• Other cleanout’s/reperforations under consideration (Q3 2018)

• Infill drilling 2018

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2018 reservoir pressure (psi)

12500

0

A’

ALess well-drained sections on flank and Lower Joanne

Crest is already being effectively drained by existing producers

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Infill Drilling

A A’

Top Joanne Sandstone Depth(Contour Interval = 100 ft)

Conclusions

• Concern over the deliverability of Lower Joanne, pre-production

• PLT’s fundamentally changed the way we modelled the reservoir

• Management and JV support of continued data acquisition was critical

• Added production and EUR through interventions

• Data has unlocked potential value, with a low cost

• Future infill drilling / well intervention planned

May 9, 201712

Knowledge is of no value unless you put it into practice – “Anton Chekhov”

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Thanks to Our Co-venturers

• Jasmine co-venturers

May 9, 201713 DEVEX 2017