the machar story: developing a complex fractured chalk field · the machar story: developing a...

The Machar Story: Developing a Complex Fractured Chalk Field Yann Jehanno DEVEX, Wednesday 12th May 2010

Introduction

•  Overview of the Machar structure

•  Major development phases & key learnings

−  The Extended Well Test

−  The early development

−  The production decline

−  Machar rejuvenation

•  Conclusions and Machar future

‘Ben’ Machar

•  Machar is a 35km subsea tie-back to Eastern Trough Area Project facility at Marnock field. 130km east of Aberdeen - 95m water

•  Salt Diapir - Fractured Chalk (+ Palaeocene Sand). STOIIP~500mmstbo

•  Main Field is developed in Western and Northern Areas, Eastern flank development is in progress

o

Top Chalk Depth Structure viewed from the south

TOP CHALK DEPTHMetres TVDss

19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE

Producer completionInjector completionShut-in wells

5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...

..12/z.16OWC @ top FortiesOWC @ top ChalkSlump limits

2..

.Mapping from

PSDM finalised 2007

A04Z(W125)

Western Area

Northern Area

Eastern Area

Machar phased development

•  Key events

•  Key learnings

Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Decline79%/year

Decline46%/year

’94-96 EWT’98 Core

Area Dev.’08-10 redev.

Gas-liftinst.

PWRI well #3

Jan-94

Jul-94

Jan-95

Jul-95

Jan-96

Jul-96

Jan-97

Jul-97

Oil

prod

uctio

n

Wat

er p

rodu

ctio

n

PW181 PW120 PW121 PW122 PW123 PW124 PW125 PW125ST PW126 PW127 PW128 PW129 IW181

Early time – Field Appraisal – EWT results Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Decline79%/year

Decline46%/year

’94-96 EWT’98 Core


Gas-liftinst.

PWRI well #3

•  Natural depletion informed on the connected volume

•  Water injection informed on the pressure maintenance and imbibition efficiency

Jul-97

Jan-98

Jul-98

Jan-99

Jul-99

Jan-00

Jul-00

Jan-01

Jul-01

Jan-02

Jul-02

Jan-03

Oil

prod

uctio

n

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Wat

er-c

ut (f

ract

ion)

PW181 PW120 PW121 PW122 PW123 PW124 PW125 PW125ST PW126 PW127 PW128 PW129 WCUT

Early time – Western Chalk Area development Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Decline79%/year

Decline46%/year

’94-96 EWT’98 Core


Gas-liftinst.

PWRI well #3

•  Production plateau achieved through only three cased/perfed/stimulated wells

•  Dramatic water breakthrough due to high offtakes

Decline 46%/year

Jan-00

Jul-00

Jan-01

Jul-01

Jan-02

Jul-02

Jan-03

Jul-03

Jan-04

Jul-04

Jan-05

Jul-05

Jan-06

Jul-06

Jan-07

Jul-07

Jan-08O

il pr

oduc

tion

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Wat

er-c

ut (f

ract

ion)


Field development progress (1) Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Decline79%/year

Decline46%/year

’94-96 EWT’98 Core


Gas-liftinst.

PWRI well #3

•  Development of other field parts

•  Field production highlights that gas-lift and offtake levels are critical production levers

Decline 46%/year => Gas lift inst. Decline 79%/year

Top C halk dip -‐ deg rees S lump lim it uncertainty

W125

W127

Northern Area Chalk Development (1)


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...


2..

.Mapping from

PSDM finalised 2007

A04Z(W125)


Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

W125


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...


2..

.Mapping from

PSDM finalised 2007

A04Z(W125)

W127

Geological interpretationConcentric slump

fractures driven by diapir, but in compression(semi-‐open fractures)

Concentric fractures orientation driven by diapir, but in extension

(open fractures)

W182 W127

W125 W125ST

W125 results => slumped reservoir has low frac perms; suboptimal stimulation

W127 results => Eastern slump margin is a pressure barrier; slumped features

decrease frac perms

The Palaeocene Development •  Exploration phase demonstrated that

Palaeocene productivity could be commercial

•  Despite Chalk depletion, Reservoir Uncertainty Studies demonstrated that Palaeocene could retain oil

•  Palaeocene development viability was confirmed with the successful drilling of Machar Core Area Development (CAD) well

2600

85010501250145016501850

V ertical S ection (m )

m T

VD

SS

T op Fo rties

T op L is ta

T op M auree n M 3

T op M auree n M 2

T op M auree n M 2 - M a in S and

T op M auree n M 1

T op E ko fisk

F au lts

2 3 /26a-A0 9 D F S

A 09Z D FS

P ilo t H o le Tops

M ain Bore T ops

M ain Bore S ands

M ain Bore L sts

S and s

1600

1800

2000

2200

2400

2600

85010501250145016501850

V ertical S ection (m )

m T

VD

SS

T op Fo rties

T op L is ta

T op M auree n M 3

T op M auree n M 2

T op M auree n M 2 - M a in S and

T op M auree n M 1

T op E ko fisk

F au lts

2 3 /26a-A0 9 D F S

A 09Z D FS

P ilo t H o le Tops

M ain Bore T ops

M ain Bore S ands

M ain Bore L sts

S and s

1600

1800

2000

2200

2400

1600

1800

2000

2200

2400

M5 Fault

M7 Fault

M6 Fault Oil Bearing – All Perforated intervals

Water Bearing M1 sand

Thin Oil Bearing M1 sand above water sand

Oil Bearing – Not Perforated

Thin Oil Bearing – Sand in Hanging wall

100% Swept Interval


Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

W128


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A04Y(W125ST)

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...

..12/z.16

2..

.Mapping from

PSDM finalised 2007

A04Z(W125)

OWC @ top FortiesOWC @ top ChalkSlump limits

Pilot well

Production well

Lower perm sands perfed in Apr 06

High perm sands perfed

in Feb 08

W128 add-perfs

1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029

Mac

har a

nnua

lised

pro

duct

ion

(gro

ss m

boed

)

How did Machar look early 2008?

•  Dramatic production decline of 79% (2007)

•  Several wells were shut-in or choked back due to PWRI constraints, low well productivity or low pressure support

•  Machar East drilling was postponed

•  Forecast recovery from the field was low

Solid: Base production

Graded: Sanctioned developments

Eastern flank development – Pushing seismic limits

•  Latest seismic reprocessing results justified the Machar East project

•  ME2 Injector sanction in January 2010 to progress the Eastern Flank development

1996 Field Development Plan (Post-stack Time) 2003 (Pre-stack Time) 2007 (Pre-stack depth)

~1km

Core Area

North Area

MacharEast well

MacharEast 2 well


Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Machar East W129

1990 2003 2008

1990 post-‐stack time m ig ration 2003 pre-‐stack time mig ration 2008 pre-‐stack depth m ig ration

Chalk Reservoir

Jan-07

Jul-07

Jan-08

Jul-08

Jan-09

Jul-09

Oil

prod

uctio

n

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Wat

er-c

ut (f

ract

ion)


Field development progress (2) Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

Decline79%/year

Decline46%/year

’94-96 EWT’98 Core


Gas-liftinst.

PWRI well #3

•  Progress development of other field parts

•  Field production highlights that voidage and water disposal capacity are critical production levers

Decline 79%/year => 3rd PWRI well

Western Area reservoir pressure stabilisation => Decline 20%/year

Top C halk dip -‐ deg rees S lump lim it uncertainty

W125

W127

W125ST

Northern Area Chalk Development (2) Machar oil production & water-cut

Jan-94

Jan-95

Jan-96

Jan-97

Jan-98

Jan-99

Jan-00

Jan-01

Jan-02

Jan-03

Jan-04

Jan-05

Jan-06

Jan-07

Jan-08

Jan-09

Oil

prod

uctio

n (s

tbd)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

wat

er-c

ut (%

)

QOP

WCUT

W125


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...


2..

.Mapping from

PSDM finalised 2007

A04Z(W125)

W127 W125ST

Geological interpretationConcentric slump

fractures driven by diapir, but in compression(semi-‐open fractures)

Concentric fractures orientation driven by diapir, but in extension

(open fractures)

W182 W127

W125 W125ST


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A04Y(W125ST)

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ...

..12/z.16

2..

.Mapping from

PSDM finalised 2007

A04Z(W125)

OWC @ top FortiesOWC @ top ChalkSlump limits

W125 results => slumped reservoir has low frac perms; suboptimal stimulation

W127 results => Eastern slump contour is a pressure barrier; slumped features

decrease frac perms

W125ST results => Low frac perms need focused stimulation

to achieve critical productivity

Machar East/W129 results => Successful results changed Machar perception and attracted further interest and investment

W129

Machar Activity 2008-2011

2007/8: Seismic East Flank ‘Illumination’

2008: Well Planning & Drilling (W129)

2008/9: North Area W125 Review 2009: Well Planning

& Drilling W125ST)

2009: ME2 injector Planning 2008: Field Oil

Decline Reduction

2009: Full Field Modelling Activities

2009: Deep Dive Reservoir Technical

Limit session

2009: Mechanistic Modelling Study

2010: 9 layer 100x100m dual porosity model

2010-2013: Infill Wells Planning & Drilling

2009-10: Infill Targets Screening Studies

2010: ME2 injector Drilling Mid-2010

2008/9: Successful wells dewatering

with 3rd PWRI

2010: Depressurisation volumes characterisation with coreflood study


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A04Y(W125ST)

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ..

.

..12/z. 16

OWC @ top FortiesOWC @ top Chalk

2

..

.Mapping from

PSDM finalised 2007

A04Z(W125)


19Y19Z

.

A01(W120)

20Y(W121)

A06(W124)

19

A09Z(W128)

..

13

13Z

10

10Z

~1km

A04Y(W125ST)

A07(W126)

18Z(W181)

A05Z(W182)

6Y(W122)

A08(W127)

A02(W123)

1RE


5

Block 23/26A

A03 (W180)

W129 (Machar East)

ME2.

. ..

.

..12/z. 16

OWC @ top FortiesOWC @ top Chalk

2

..

.Mapping from

PSDM finalised 2007

A04Z(W125)

Conclusions and Machar Future Redevelopment

•  Stabilising the base production decline and building up a resource progression track record:

−  Changed the field perception

−  Attracted further investments

•  Ensure PWRI capacity is big enough to keep wet wells flowing

1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029

Mac

har a

nnua

lised

pro

duct

ion

(gro

ss m

boed

)

1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029

Mac

har a

nnua

lised

pro

duct

ion

(gro

ss m

boed

)

Solid: Base production Graded: Sanctioned developments

Specked: Hopper options

•  Drill wells & multilaterals to increase recovery

•  Keep increasing the field recovery factor, by being creative and open minded to new technologies and reservoir mechanisms

•  Understand the blowdown mechanisms and prize

Acknowledgements

•  Neil Blackburn

•  Davide Casabianca

•  Alastair Govan

•  Rachel McRonald

•  Sara Newns

•  Phil Townsend

•  Melanie Westergaard

•  Marie O’Hanlon

•  Chris Pearse

•  Richard Pollard

•  David Richards

•  Mary Ward

•  Adrian Zett

the machar story: developing a complex fractured chalk field · the machar story: developing a...

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