A Perspective on Experience on U.S Norwegian Co-operation on EOR at COREC Centre at Rogaland and University of Bergen David R. Zornes Manager – Reservoir Mechanisms Group Bartlesville Technology Center

Outline of Presentation

• • History of COP and Norway Primary Areas of Research – Technical Needs and Issues are Primary Drivers • Why Cooperation is Our Practice

Ekofisk Research Timeline

450 400 350 300 250 200 150 100 50 0 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009

Preliminary EOR Lab Tests Initiate Waterflood in Tor Fm. Based on Initial Characterization .

Ekofisk II EOR Screening.

Subsidence Observed. Start Rock Mechanics Testing & Modeling Expand Waterflood with Updated Lab & Modeling Results.

Key Research Directions

• • • Improved Recovery Methods.

– Mechanisms and Endpoints.

– CO2, HC WAG, MIOR, Imbibition Enh., Air Subsidence and Compaction.

– Recognition and Forecasting.

– Field Monitoring & Fully Coupled Modeling CO 2 Sequestration – CH 4 from Hydrates.

Production

Improved Waterflood Performance

• • Initial Studies Suggested Waterflood Would NOT Be Very Successful.

After Successful Pilot – Lab and Theoretical Studies Focused on Mechanisms and Endpoints.

• Recovery Factor Improvements.

50 40 30 20 10 0 1971 1976 1981 1986 Ekofisk Field 1991 1996 2001

• •

MRI Imaging of Fluids Crossing Fracture in Chalk

Mechanism for Crossing Strongly Dependent Upon Chalk Wettability. How and When Crosses Fracture to Next Block is Critical Information in Simulation Model.

A

Water Wet

B

Less Water Wet

EOR Evaluation Studies Laboratory & Reservoir Simulation

1998 Study for NPD – HC WAG

6% Recovery Inc. Most Feasible in Current Environment

.

– N2 WAG

Not Economical.

– CO2 WAG

6% Recovery Inc. Requires CO2 Source. Current COREC Project

.

– Air Injection

Good Recovery – Last Stage. EU Thermie Project Involving Rogaland, Bath and Contractors.

– MEOR

Low Recovery but Inexpensive.

Subsidence of Ekofisk Field

• • • Recognized in 1984.

Engineering Response – Jack Up Platforms.

Research – Fundamentals of Chalk Compressibility Subsidence Modeling/Forecasts.

1978 1986

Chalk Rock Mechanics

• Laboratory Stress / Strain Tests Determine Extent of Potential Compaction.

• Incorporated into Subsidence Model.

• BTC – HiS Laboratory Collaboration. 0.18

0.16

0.14

0.12

0.1

0.08

0.06

Ultimate Axial Strains at 6 kpsi for Ekofisk & Eldfisk Reservoir Chalks Measured Data and Models for Waterfree and Water-weakened Chalks

44%

Measured strains for water-wetted, water-weakened chalk Measured strains for waterfree Ekofisk chalk Model water-wetted Ekofisk chalk Model waterfree Ekofisk chalk Eldfisk waterfree chalk Eldfisk water-weakened chalk

30% 7x Str ain

0.04

0.02

0 18 20 22 24 26 28 30 32 34 36 Initial Porosity, % 38 40 42 44 46 48 50

Subsidence Modeling

1 0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0 6

North Sea Ultimate Subsidence - 2029

Ultimate Subsidence Risk Profile (Final Model Parameters) P50=14m P90=19m 8 10 P10=9.5m

12 14 16 18 Subsidence (m) 20 22 24 26

CO2 Sequestration – Hydrate Production Research

• • University of Bergen – ConocoPhillips Collaborative Laboratory and Theoretical Study.

State-of-Art Research Draws on Expertise from Each Group.

– Form and Produce Gas Hydrates in Lab.

– MRI Monitor Reaction Rates and Paths.

Water Saturated Core Hydrate CH4 Gas

Collaboration and Training with Norwegian Universities

• Students Worked on Ekofisk-Related Projects at BTC Since 1980’s – Numerous MS/Dipl. Degrees, 8 Ph.D.’s (

Including Several Current Faculty

).

– NTNU – Dept. of Petroleum Engineering.

– University of Bergen – Dept. Physics.

– Høgskolen i Stavanger – Dept. Petrol. Eng.

Industry-Supported Research

•

Joint Chalk Research

. (1970’s – Current). Broad-Based Programs with Emphasis on Industry-University Collaboration. Phillips/CoP as Major Participant in All Stages.

•

University Research Centres

– –

CIPR

(University of Bergen)

COREC

(University College Stavanger) • Ekofisk Area PL018 Co-Venturers Sponsored Internal Research.

Lessons from Ekofisk-Related Research on Improved Recovery

•

Well-Defined Goals:

Fundamental Questions.

Problems Linked to

•

Long-Term:

Allowed for False Starts, Change in Direction.

•

Multi-Disciplinary:

Left “Business as Usual” Behind, Overcame Tradition and Bias.

Advantages of Cooperation

• • • • • • • Develop Additional Expertise Multi-Discipline Approach Longer Term Possible on Fundamentals Potential for Lower Costs With Students Leverage Our Internal Resources Network of Researchers/Relationships Norwegian Institutes Increasingly Involved

Acknowledgements

• • • • ConocoPhillips Management Reservoir Recovery Mechanisms Staff – Past and Present U. of Bergen, Rogaland University Numerous COP Employees

The End Questions???