Unconventional Resources Tight Gas Sands Shale Gas
Content
1
Tight Gas Sands
4 7
1
3
6
1.
2
2.
3.
4.
5.
6.
7.
8.
8
5
2
Illizi Basin: Cambro
Cambro--ordovician
Ahnet
Ah t Basin:
B i Cambro
C b -ordovician
Cambrod i i +Siegenian
Si
i – Gedinnian
G di i + Strunian
St
i
Bechar –Timimoun Basin: Cambro
Cambro--ordvician
Gassi Touil – Rhourde Nouss Area: Cambro
Cambro--ordovician
Reggane Basin: CambroCambro-ordovician + Lower Devonian
Tindouf Basin : CambroCambro-ordovician + Lower Devonian
Berkine Basin: Cambro
Cambro--ordovician (Ultra Tight Gas Sands
Sands))
Boubernous Area: Cambro
Cambro--ordovician (Ultra Tight Gas Sands
Sands))
The limits are established from a ranking of the sedimentary basins
Unconventional Resources Tight Sand/ BCGA
Ordovician Illizi Basin Example
BCGA
3
Unconventional Resources - Tight Sand/ BCGA
((Ordovician Ahnet & Reggane
gg
Basin))
Sbaa Basin
Reggane
gg
Basin
Hamra Quartzite
Atchane Sandstone
4
Ahnet Basin
Unconventional Resources -Tight Sand/ BCGA
Ordovician Reggane Basin Example
5
GIIP Ordovicien 80 BCM
Resources :50 BCM (TIO, AZS)
ACTION PLAN
Completed
Definition of the shale gas plays:
plays: To make a regional evaluation by using all the
available data (cores, logs, seismic maps, shows and others)
others)..
Completed
Consolidation of the database:
database: To gather complementary data in various
basins specific open hole logs shale gas logging (Elemental device
“spectroscopy”, Array induction, Magnetic Resonance, Sonic with
anisotropic determination, GR, Resistivity, Image log & Neutron
Density…
Density
…).
Confirmation of the Concept:
On going
Detailed
D t il d Studies
St di off the
th shale
h l gas potential
t ti l off the
th main
i basins
b i
To prove the concept on 2 or 3 pilot wells by carrying out the necessary
operations :
–
Productivity of the formation
formation, tests design and other measurements
measurements.
–
Drillability of horizontal well
–
Feasibility of stimulation: type of fracs (transverse, longitudinal)
To estimate the resources and to make the economic evaluation in an
Algerian.
long term
Development phase:
phase: This phase which requires very large investments, with
regard to the volume of work to be realized and to a proven expertise
needed would be considered by calling upon specialized companies
Maturity maps of Silurian and Frasnian hot Shales
Silurian
Frasnian
2 0< Ro< 3 5% (dry gas)
2.0< Ro< 3.5% (dry gas)
1.3< Ro< 2.0% (wet gas)
0.5< Ro< 1.3% (Oil)
( )
7
Ro équ.< 0.5 % (immature)
Shale Gas Prospectivity Maps in the Saharan Platform
Silurian hot Shale
Zone Prospective
Profondeur trop Elevée (objectif Shale Gas)
Gisement de Gaz
Gisement de Gaz
PARAMETERS :
 Thickness = >20m
 TOC = >1%,
>1% Prefer > 3
3.5%
5%
 Maturity (VR) = 1.7 – 3%
 Depth = < 3000 m
Frasnian hot Shale
Shale Oil (Condensat & Gaz humide)
Shale Gas (Methane)
Well-1 Evaluation
The Upper Hot Shale has excellent petrophysical
properties The effective porosity, Kgas,
Kgas, and Sweff are
very, very good
good..
The average TOC value for the organic shales is high
high..
All of the hot shales have very high clay content with
notably high kaolinite
kaolinite,, chlorite, and smectite.
smectite. Average
clay content is ~60 wt
wt%
%. This raises concern for proppant
embedment..
embedment
High smectite content (5.1 wt
wt%
% in Upper Hot Shale)
suggests that frac fluid compatibility should be
evaluated..
evaluated
Kerogen is completely converted:
converted: Dry Gas production
Zone 2;
Pay; 79 m or 260 ft
Avg Porosity; 8.12
Avg TOC; 5.3%
GIP; 140 BCF
Avg Clay; 62%
Avg Swelling Clay; 5%
Zone 4;
Pay; 15.8 m or 52 ft
Avg Porosity; 7.3
Avg TOC; 3.9%
GIP; 47 BCF
GIP; 47 BCF
Avg Clay; 50%
Avg Swelling Clay; 4%
Preliminary results of the Frasnian Well -2
Zone 1;
Pay; 60 m or 189 ft
Avg Porosity; 7.1
71%
Avg TOC; 5.0%
GIP; 95 BCF
Zone 2;
Pay; 53 m or 174 ft
Avg Porosity; 8.3
83%
Avg TOC; 5.9%
GIP; 100 BCF
Calcareous Zone
Zone 3;
Pay; 23 m or 76 ft Avg Porosity; 6.6
66%
Avg TOC; 3.7%
GIP; 45 BCF
Comparison of the Ahnet Frasnian gas shale (Algeria)
with the main US Gas Shales (preliminary results)
Net Ft.
Pay
Avg.
g Eff.
Phi (%)
Avg.
g TOC
(wt%)
Avg.
g Sw
(%)
Avg.
g K
(nD)
Total GIP
(Bcf
Bcf/mi
/mi2)
Marcellus Shale (Wash Co)
76
8.1
3.6
19
567
59
Barnett
B
tt Sh
Shale
l (Core)
(C
)
133
8
33
3.3
24 5
24.5
299
139
Woodford Shale (Arkoma)
66
6.8
6
26.4
285
59
Atoka Shale
21
96
9.6
26
2.6
48
191
55
Fayetteville Shale
84
7.2
3.6
29.1
288
53
Haynesville
y
Shale
112
8.4
2.2
39
270
129
Eagle Ford Shale
105
6.6
2.7
23
284.5
90
Algeria (area A)
108
7.0
2.7
18
350
65
Algeria (area B)
250
8.6
4.1
23.2
360
122
Algeria (area C)
248
9.0
4.0
22
354
122
Formation
11
Shale Gas Detailed Evaluation
Consulting
Bechar
J i t Studies
Joint
St di
Tindouf
Reggane
Areas to be
Areas to be
studied
Potential of GIP in Prospective areas
PROSPECTIVE RESOURCES BASED ON GEOCHEMICAL
MODELING:
Considering that 10 to 40 % of the total volume
generated from the two main source rocks (Silurian &
Frasnian hot shales) remains within the shale gas
plays, result in a GIIP of 2650 to 10585 Tcf range from
a total generated of 26450 Tcf.
B i
Basin
G (Tcf)
Gas
(T f) Liquids
Li id (Bbbl)
Ahnet
1902
Timimoun
1925
Bechar
53
Berkine
954
215
Illizi *
106
33
TOTAL (GIIP)
4940
248
-
TECHNICALLY RECOVERABLE RESOURCES (TRR):
By using a recovery factor of 15%
15%, the total technically
recoverables resources within the prospectives areas
of the studied basins (Ahnet
Ahnet,, Timimoun
Timimoun,, Bechar,
Bechar
Berkine and Illizi) is
is:: 4940*
4940*15
15%
%= 741 Tcf
Tcf..
For comparison,
comparison
p
, TRR of shale g
gas for the USA is : 665 Tcf ((source EIA 2013
2013)).
Recovery Factors:
Factors: 20 to 50%
50% for Barnett shale, 30%
30% Haynesville shale, 20 to 40%
40% Marcellus shale
shale..
Unconventional Resources -Estimates of Shale plays
ORGANISATION/
COMPANY
ESTIMATES
DATE
REMARKS
Wood Mackenzie
529.0 Tcf of
GIIP (Silurian only)
September
2009
Estimates of gas-in-place: 529 Tcf. This study
considers only the Silurian hot shales extending
across 26,452 square miles (68,000 km²). The
extent of the hot shale has been defined by
those areas where the thickness exceeds 10m.
PETRENEL
(Jessica Hill &
Stewart Whiteley
Whiteley))
3954 Tcf
Estimated Unrisked Shale
GIIP Resources
April 2010
3954 Tcf of unrisked shale GIIP for both the
Silurian and Devonian plays in Algeria.
3409 Tcf Mean Estimate
DEGOLYER AND
MACNAUGHTON
644 Tcf of technically
recoverable resources
December
2010
(Silurian only)
EIA/ARI Resource
Assessment (2013)
14
3419 Tcf of risked GIIP
707 Tcf of technically
recoverable resources
June 2013
3400 Tcf of gas in place in the hot shale of the
Silurian (only) across the whole Saharan
platform from which over 600 Tcf would be
technically recoverable
3419 Tcf of risked shale gas in-place, with 707
Tcf as the risked,
risked technically recoverable shale
gas resource for the two significant source
rocks (the Silurian & Devonian hot shales).
SCALE COMPARISON: ALGERIA vs US Shale Gas Plays
1000km
1000km
1000km
Drivers and indicators
for shale gas development in Algeria
Large Resources
Wood McKenzie (2009) : Over 500 Tcf of gas in place in the hot shale of the Silurian
DeGolyer & MacNaughton (2010) : 3400 Tcf of gas in place in the hot shale of the Silurian across
the whole Saharan platform from which over 600 Tcf would be technically recoverable
PETRENEL (2010) : 4000 Tcf of unrisked
shale gas in place in the hot shale of the
Silurian and Frasnian.
⇒ >30 Bcf/mi2 required
q
for commercial
success.
EIA (2011) annual report :
231 Tcf of technically recoverable gas in the
hot shale of Berkine, Illizi and Tindouf
basins.
(the most prospective basins such as Ahnet
and Gourara are not included)
EIA (2013) annual report:
707 Tcf of technically recoverable gas in the
hot shale in Algeria
From “Shale Gas Potential of North Africa and the Near East”, by
Stewart Whiteley & Jessica Hill, PETRENEL, Presented at the SMI
Unconventional Gas Conference, London 16th-17th March 2011
Drivers and indicators
for shale gas development in Algeria
1. Large resources : International organizations estimations of Algerian shale gas
resources are confirmed by regional screening studies and evaluation results on
several wells (logs and cores) carried out by Sonatrach
2. Evaluating and developing shale gas in Algeria is becoming a priority: Several shale
gas evaluation projects concerning different basins are in process or have been
finalized ⇒ regional screening completed
completed, pilot wells drilled and completed in
2013.
3. Possibility to produce dry gas and liquids : wide range of maturity → dry and wet
gas in
i th
the western
t
b
basins
i and
d shale
h l oilil with
ith hi
high
h reservoir
i pressures iin th
the eastern
t
basins
4. Possibilityy to develop
p different sands in synergy,
y gy, increasing
g commerciality
y and
maximizing benefits : Presence of conventional and tight sands formations beneath
or above the hot shale intervals of the Silurian and the Frasnian.
5 Availability of water : aquifers with huge volumes of water extending over large
5.
areas (from eastern border of Algeria to the western basin of Ahnet)…but industrial
usage for shale gas development is regulated.
Drivers and indicators
for shale gas development in Algeria
6. increasing activity of drilling and hydraulic fracturing operations and new
pipeline construction projects (western basins) : this is due to several
conventional and/or tight sands fields to be developed in the near future (ex.
Ah t Tinhert
Ahnet,
Ti h t ….))
7. Opportunity for developing shale gas with reduced investment (eastern basins) :
Availabilityy of infrastructure, surface facilities and pipeline network with
significant capacities
8. Increasing gas demand worldwide (particularly in Europe)
9. Historical partnership of Sonatrach with international oil and gas companies :
well-known concession procedures, collaboration and shared experience …etc
10 Resources are owned by government
10.
11. Adapted legislation ( 2013 )
12 Large concession block
12.
13. No surface use concerns
14. Social acceptance : historical oil and gas industry in Algeria
Some general concerns for shale gas development
• Technology transfer of and know-how : Although Sonatrach has acquired a
significant
g
experience
p
in hydraulic
y
fracturing
g ((since 90s),
) a p
program
g
for
preparing a qualified human resources in shale gas evaluation and
development is undertaken by Sonatrach. In addition, collaboration with
experienced oil and gas companies in shale gas development as well as
service companies is an option to achieve technology transfer objectives.
•
Availability of drilling rig,
rig frac units…etc
units etc : currently,
currently there is no major
competitive climate between service companies ⇒ costs are kept high but with
increasing activity they will be reduced
•
Flow back (frac water) treatment and disposal and other HSE concerns
•
Economics : what is the economical breakeven ?
 Further evaluation work has to be carried out to reduce uncertainties (pilot
wells)
Tight Gas Sands
4 7
1
3
6
1.
2
2.
3.
4.
5.
6.
7.
8.
8
5
2
Illizi Basin: Cambro
Cambro--ordovician
Ahnet
Ah t Basin:
B i Cambro
C b -ordovician
Cambrod i i +Siegenian
Si
i – Gedinnian
G di i + Strunian
St
i
Bechar –Timimoun Basin: Cambro
Cambro--ordvician
Gassi Touil – Rhourde Nouss Area: Cambro
Cambro--ordovician
Reggane Basin: CambroCambro-ordovician + Lower Devonian
Tindouf Basin : CambroCambro-ordovician + Lower Devonian
Berkine Basin: Cambro
Cambro--ordovician (Ultra Tight Gas Sands
Sands))
Boubernous Area: Cambro
Cambro--ordovician (Ultra Tight Gas Sands
Sands))
The limits are established from a ranking of the sedimentary basins
Unconventional Resources Tight Sand/ BCGA
Ordovician Illizi Basin Example
BCGA
3
Unconventional Resources - Tight Sand/ BCGA
((Ordovician Ahnet & Reggane
gg
Basin))
Sbaa Basin
Reggane
gg
Basin
Hamra Quartzite
Atchane Sandstone
4
Ahnet Basin
Unconventional Resources -Tight Sand/ BCGA
Ordovician Reggane Basin Example
5
GIIP Ordovicien 80 BCM
Resources :50 BCM (TIO, AZS)
ACTION PLAN
Completed
Definition of the shale gas plays:
plays: To make a regional evaluation by using all the
available data (cores, logs, seismic maps, shows and others)
others)..
Completed
Consolidation of the database:
database: To gather complementary data in various
basins specific open hole logs shale gas logging (Elemental device
“spectroscopy”, Array induction, Magnetic Resonance, Sonic with
anisotropic determination, GR, Resistivity, Image log & Neutron
Density…
Density
…).
Confirmation of the Concept:
On going
Detailed
D t il d Studies
St di off the
th shale
h l gas potential
t ti l off the
th main
i basins
b i
To prove the concept on 2 or 3 pilot wells by carrying out the necessary
operations :
–
Productivity of the formation
formation, tests design and other measurements
measurements.
–
Drillability of horizontal well
–
Feasibility of stimulation: type of fracs (transverse, longitudinal)
To estimate the resources and to make the economic evaluation in an
Algerian.
long term
Development phase:
phase: This phase which requires very large investments, with
regard to the volume of work to be realized and to a proven expertise
needed would be considered by calling upon specialized companies
Maturity maps of Silurian and Frasnian hot Shales
Silurian
Frasnian
2 0< Ro< 3 5% (dry gas)
2.0< Ro< 3.5% (dry gas)
1.3< Ro< 2.0% (wet gas)
0.5< Ro< 1.3% (Oil)
( )
7
Ro équ.< 0.5 % (immature)
Shale Gas Prospectivity Maps in the Saharan Platform
Silurian hot Shale
Zone Prospective
Profondeur trop Elevée (objectif Shale Gas)
Gisement de Gaz
Gisement de Gaz
PARAMETERS :
 Thickness = >20m
 TOC = >1%,
>1% Prefer > 3
3.5%
5%
 Maturity (VR) = 1.7 – 3%
 Depth = < 3000 m
Frasnian hot Shale
Shale Oil (Condensat & Gaz humide)
Shale Gas (Methane)
Well-1 Evaluation
The Upper Hot Shale has excellent petrophysical
properties The effective porosity, Kgas,
Kgas, and Sweff are
very, very good
good..
The average TOC value for the organic shales is high
high..
All of the hot shales have very high clay content with
notably high kaolinite
kaolinite,, chlorite, and smectite.
smectite. Average
clay content is ~60 wt
wt%
%. This raises concern for proppant
embedment..
embedment
High smectite content (5.1 wt
wt%
% in Upper Hot Shale)
suggests that frac fluid compatibility should be
evaluated..
evaluated
Kerogen is completely converted:
converted: Dry Gas production
Zone 2;
Pay; 79 m or 260 ft
Avg Porosity; 8.12
Avg TOC; 5.3%
GIP; 140 BCF
Avg Clay; 62%
Avg Swelling Clay; 5%
Zone 4;
Pay; 15.8 m or 52 ft
Avg Porosity; 7.3
Avg TOC; 3.9%
GIP; 47 BCF
GIP; 47 BCF
Avg Clay; 50%
Avg Swelling Clay; 4%
Preliminary results of the Frasnian Well -2
Zone 1;
Pay; 60 m or 189 ft
Avg Porosity; 7.1
71%
Avg TOC; 5.0%
GIP; 95 BCF
Zone 2;
Pay; 53 m or 174 ft
Avg Porosity; 8.3
83%
Avg TOC; 5.9%
GIP; 100 BCF
Calcareous Zone
Zone 3;
Pay; 23 m or 76 ft Avg Porosity; 6.6
66%
Avg TOC; 3.7%
GIP; 45 BCF
Comparison of the Ahnet Frasnian gas shale (Algeria)
with the main US Gas Shales (preliminary results)
Net Ft.
Pay
Avg.
g Eff.
Phi (%)
Avg.
g TOC
(wt%)
Avg.
g Sw
(%)
Avg.
g K
(nD)
Total GIP
(Bcf
Bcf/mi
/mi2)
Marcellus Shale (Wash Co)
76
8.1
3.6
19
567
59
Barnett
B
tt Sh
Shale
l (Core)
(C
)
133
8
33
3.3
24 5
24.5
299
139
Woodford Shale (Arkoma)
66
6.8
6
26.4
285
59
Atoka Shale
21
96
9.6
26
2.6
48
191
55
Fayetteville Shale
84
7.2
3.6
29.1
288
53
Haynesville
y
Shale
112
8.4
2.2
39
270
129
Eagle Ford Shale
105
6.6
2.7
23
284.5
90
Algeria (area A)
108
7.0
2.7
18
350
65
Algeria (area B)
250
8.6
4.1
23.2
360
122
Algeria (area C)
248
9.0
4.0
22
354
122
Formation
11
Shale Gas Detailed Evaluation
Consulting
Bechar
J i t Studies
Joint
St di
Tindouf
Reggane
Areas to be
Areas to be
studied
Potential of GIP in Prospective areas
PROSPECTIVE RESOURCES BASED ON GEOCHEMICAL
MODELING:
Considering that 10 to 40 % of the total volume
generated from the two main source rocks (Silurian &
Frasnian hot shales) remains within the shale gas
plays, result in a GIIP of 2650 to 10585 Tcf range from
a total generated of 26450 Tcf.
B i
Basin
G (Tcf)
Gas
(T f) Liquids
Li id (Bbbl)
Ahnet
1902
Timimoun
1925
Bechar
53
Berkine
954
215
Illizi *
106
33
TOTAL (GIIP)
4940
248
-
TECHNICALLY RECOVERABLE RESOURCES (TRR):
By using a recovery factor of 15%
15%, the total technically
recoverables resources within the prospectives areas
of the studied basins (Ahnet
Ahnet,, Timimoun
Timimoun,, Bechar,
Bechar
Berkine and Illizi) is
is:: 4940*
4940*15
15%
%= 741 Tcf
Tcf..
For comparison,
comparison
p
, TRR of shale g
gas for the USA is : 665 Tcf ((source EIA 2013
2013)).
Recovery Factors:
Factors: 20 to 50%
50% for Barnett shale, 30%
30% Haynesville shale, 20 to 40%
40% Marcellus shale
shale..
Unconventional Resources -Estimates of Shale plays
ORGANISATION/
COMPANY
ESTIMATES
DATE
REMARKS
Wood Mackenzie
529.0 Tcf of
GIIP (Silurian only)
September
2009
Estimates of gas-in-place: 529 Tcf. This study
considers only the Silurian hot shales extending
across 26,452 square miles (68,000 km²). The
extent of the hot shale has been defined by
those areas where the thickness exceeds 10m.
PETRENEL
(Jessica Hill &
Stewart Whiteley
Whiteley))
3954 Tcf
Estimated Unrisked Shale
GIIP Resources
April 2010
3954 Tcf of unrisked shale GIIP for both the
Silurian and Devonian plays in Algeria.
3409 Tcf Mean Estimate
DEGOLYER AND
MACNAUGHTON
644 Tcf of technically
recoverable resources
December
2010
(Silurian only)
EIA/ARI Resource
Assessment (2013)
14
3419 Tcf of risked GIIP
707 Tcf of technically
recoverable resources
June 2013
3400 Tcf of gas in place in the hot shale of the
Silurian (only) across the whole Saharan
platform from which over 600 Tcf would be
technically recoverable
3419 Tcf of risked shale gas in-place, with 707
Tcf as the risked,
risked technically recoverable shale
gas resource for the two significant source
rocks (the Silurian & Devonian hot shales).
SCALE COMPARISON: ALGERIA vs US Shale Gas Plays
1000km
1000km
1000km
Drivers and indicators
for shale gas development in Algeria
Large Resources
Wood McKenzie (2009) : Over 500 Tcf of gas in place in the hot shale of the Silurian
DeGolyer & MacNaughton (2010) : 3400 Tcf of gas in place in the hot shale of the Silurian across
the whole Saharan platform from which over 600 Tcf would be technically recoverable
PETRENEL (2010) : 4000 Tcf of unrisked
shale gas in place in the hot shale of the
Silurian and Frasnian.
⇒ >30 Bcf/mi2 required
q
for commercial
success.
EIA (2011) annual report :
231 Tcf of technically recoverable gas in the
hot shale of Berkine, Illizi and Tindouf
basins.
(the most prospective basins such as Ahnet
and Gourara are not included)
EIA (2013) annual report:
707 Tcf of technically recoverable gas in the
hot shale in Algeria
From “Shale Gas Potential of North Africa and the Near East”, by
Stewart Whiteley & Jessica Hill, PETRENEL, Presented at the SMI
Unconventional Gas Conference, London 16th-17th March 2011
Drivers and indicators
for shale gas development in Algeria
1. Large resources : International organizations estimations of Algerian shale gas
resources are confirmed by regional screening studies and evaluation results on
several wells (logs and cores) carried out by Sonatrach
2. Evaluating and developing shale gas in Algeria is becoming a priority: Several shale
gas evaluation projects concerning different basins are in process or have been
finalized ⇒ regional screening completed
completed, pilot wells drilled and completed in
2013.
3. Possibility to produce dry gas and liquids : wide range of maturity → dry and wet
gas in
i th
the western
t
b
basins
i and
d shale
h l oilil with
ith hi
high
h reservoir
i pressures iin th
the eastern
t
basins
4. Possibilityy to develop
p different sands in synergy,
y gy, increasing
g commerciality
y and
maximizing benefits : Presence of conventional and tight sands formations beneath
or above the hot shale intervals of the Silurian and the Frasnian.
5 Availability of water : aquifers with huge volumes of water extending over large
5.
areas (from eastern border of Algeria to the western basin of Ahnet)…but industrial
usage for shale gas development is regulated.
Drivers and indicators
for shale gas development in Algeria
6. increasing activity of drilling and hydraulic fracturing operations and new
pipeline construction projects (western basins) : this is due to several
conventional and/or tight sands fields to be developed in the near future (ex.
Ah t Tinhert
Ahnet,
Ti h t ….))
7. Opportunity for developing shale gas with reduced investment (eastern basins) :
Availabilityy of infrastructure, surface facilities and pipeline network with
significant capacities
8. Increasing gas demand worldwide (particularly in Europe)
9. Historical partnership of Sonatrach with international oil and gas companies :
well-known concession procedures, collaboration and shared experience …etc
10 Resources are owned by government
10.
11. Adapted legislation ( 2013 )
12 Large concession block
12.
13. No surface use concerns
14. Social acceptance : historical oil and gas industry in Algeria
Some general concerns for shale gas development
• Technology transfer of and know-how : Although Sonatrach has acquired a
significant
g
experience
p
in hydraulic
y
fracturing
g ((since 90s),
) a p
program
g
for
preparing a qualified human resources in shale gas evaluation and
development is undertaken by Sonatrach. In addition, collaboration with
experienced oil and gas companies in shale gas development as well as
service companies is an option to achieve technology transfer objectives.
•
Availability of drilling rig,
rig frac units…etc
units etc : currently,
currently there is no major
competitive climate between service companies ⇒ costs are kept high but with
increasing activity they will be reduced
•
Flow back (frac water) treatment and disposal and other HSE concerns
•
Economics : what is the economical breakeven ?
 Further evaluation work has to be carried out to reduce uncertainties (pilot
wells)
