Classification: Internal Status: Draft

Eksperter i Team – Gullfakslandsbyen 2008

Gullfaks historie – et norsk svennestykke Leif-Kristian Teviterå, Corporate trainee, StatoilHydro Gullfaks satelitter Petec

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Structural Depthmap – Base Structural Depthmap – Base CretaceousCretaceous

Area : 50 km2

Top Structure : 1700 m TVD

Dipping : 0-20 West

Oil-water contact : 1947 m TVD

Initial pressue : 310 bar

Bubblepoint pressure : 220 bar

Initial temprature : 72 deg C

Formation volume factor : 1,2

Oil viscosity : 1.2 cp

Oil gravity : 36.9 API

Gullfaks reservoir data

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Gullfaks main field, WE cross-section

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The Gullfaks-field

Classification: Internal Status: Draft

For at en skal få danne et olje/gas felt er det flere forhold som må oppfylles :

Reservoir

Trap

Reservoar

Felle

Seal Segl

Modning og migrasjon av hydrokarboner

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•

Infill of oil (migration)

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Gullfaks Production Profile (incl. IOR) and the Timing of the 3D Seismic Surveys

1986 1990 1994 1998 2002 2006 2010 20140

50

100

150

200

Ra

te S

m3

/sd

x 1

00

0

1985

SU

RV

EY

1995

SU

RV

EY

1996

SU

RV

EY

OIL

WATER

IOR OIL

WATER INJECTED

1999

SU

RV

EY

2003

SU

RV

EY

2001

OB

C

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Implemented Oil Recovery Measures at Gullfaks

• Water injection from start

• Upgrading of water injection capacities

• 4D seismic and inversion

• Tracers

• Hydraulic fracturing in low perm reservoirs

• WAG (Water alternating gas) injection

• ”Huff and puff” gas injection

• Extensive exploration activity within drilling reach from platforms => new volumes

• Sand control in most wells

• ”Designer wells” (horizontal, 3D)

• Extended reach drilling (10 km)

• Monobore completions

• DIACS -”Smart wells”

• Multilateral wells (ML)

• Coiled Tubing drilling (CT)

• Through tubing drilling (TTRD)

• Rig assisted snubbing (RAS)

• Underbalanced drilling (UBD)

• Expandable liners

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Oil Recovery Measures studied

Studied, but discarded:

• Surfactant injection (1992 pilot)

• Gel blocking (1992 pilot)

• CO2 miscible injection (2000)

• Aerobic Microbiological EOR

(2006)

Currently being studied:

• Reservoir characterisation, remaining saturation and relative permeability

• Temprature effects

• Building new reservoir simulation models

• WAG evaluations

• EOR with water based methods

• CO2 studies

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Well targets

Gullfaks in the past and present;

Steak vs. ragu

Gullfaks

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Korleis drive eit felt som er på haleproduksjon?

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Finne nye boremål og planlegge nye brønnar utgjør størsteparten av

arbeidsoppgavene til petroleumsteknisk (Petek) personell på Gullfaks

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Saturation log34/10 C-3

Etive-formation

1990 04.1993 02.1994 12.1996

By repeated well-tests we can monitor how the flooding affect our reservoirs