In Salah CO2 Storage Project

J.A. White*, L. Chiaramonte, S. Ezzedine, W. Foxall, Y. Hao, W. McNab, and A. Ramirez Lawrence Livermore National Laboratory Project Number: FWP-FEW0174 Task 2

U.S. Department of Energy National Energy Technology Laboratory

Carbon Storage R&D Project Review Meeting August 20-22, 2013

This work was performed under the auspices of the U.S. Department of Energy by

Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Data and co-funding were provided by the In Salah Joint Industry Project.

Benefit to the Program

§  This project combines sophisticated modeling tools with monitoring data sets to address fundamental challenges in interpreting storage system behavior.

§  This program meets the Carbon Storage Program goal to “conduct field tests through 2030 to support the development of BPMs for site selection, characterization, site operations, and closure practices.”

Objectives

§  Project objective is to address four fundamental challenges:

¡  Modeling of plume migration and prediction of partitioning among various trapping mechanisms

¡  Uncertainty quantification of CO2 distribution with the reservoir and potential migration pathways (e.g. damaged caprock)

¡  Understanding of fluid-induced seismicity and associated risks

¡  Definition of potential leakage source terms and their impact on a shallow groundwater aquifer

§  Success is tied to the ability to provide useful guidance to the operator.

Technical Status

§  The technical work is complete, and we are in the final reporting stage:

¡  J.A. White et al., “Geomechanical behavior of the reservoir/caprock system at the In Salah CO2 storage project”, (under review by operator).

¡  S. Ezzedine et al., “Assessing hydraulic fracturing of porous fractured media reservoirs: Application to In Salah”, (in preparation)

¡  A. Ramirez et al., “Stochastic inversion of InSAR data to detect penetration into the lower caprock at In Salah”, (in preparation).

§  In June 2011, injection operations were halted at the site to allow the operator to re-evaluate the injection strategy.

In Salah Storage Project

§  Reservoir at ~1900m, ~20m thick

§  Anticlinal structure

§  Gas with high CO2 content produced from the cap

§  Separated and re-injected through three horizontal wells on the limbs

2727

• Five gas producers• Three CO2 injectors• Initial reservoir conditions:

• P= 175bars• T = 95oC

• Reservoir is 1880m deep, 20m thick and 20 x 8km2 in area

• 3 MT CO2 have been injected (2004 to March 2009)Kb-15

Kb-13

Kb-12

Kb-11

Kb-14

Kb-501

Kb-503

Kb-502

Key Field Statistics

[In  Salah  JIP]  

Storage Complex §  950 m thick caprock

§  Grouped into main caprock and lower caprock units

§  Monitoring indicates that fluids have migrated into the lower caprock

§  No indications that the main caprock has been affected

0

200

400

600

800

1000

1200

1400

1600

1800

2000

De

pth

, m

TV

D b

rt

Cretaceous Superieur

Cretaceous Continental Intercalaire

Hercyninian Unconformity

Carboniferous Viséan Mudstone (C20)

Hot Shale (C20.7)

Tournaisian Sandstones (C10.3 and C10.2)

Devonian Sandstone (D70)

Main Caprock Units

Lower Caprock Units

Primary Storage

Characterization and Monitoring N

ort

hin

g, m

Easting, m

NS1959, UTM 31N

gas/watercontact

1997 seismicsurvey

2009 seismicsurvey

3215000

3220000

3225000

3230000

415000 420000 425000 430000

full gascolumn

KB-501

KB-502

KB-503KB-601

KB-1

KB-2

KB-4

KB-5

KB-6

KB-8

KB-9

KB-10

KB-11

KB-12

KB-14

§  Co-located storage and production

§  Seismic surveys

§  InSAR

§  Microseismic (limited).

§  Surface and aquifer monitoring

§  Others

InSAR NS1959, UTM 31N

415000 420000 425000 430000

Easting, m

3220000

3225000

3230000

Nort

hin

g, m

-10

-5

0

5

10

15

20

25

Range C

hange, m

m

Shmax

KB-501

KB-502

KB-5

KB-503

March 2010

Possible deformation mechanism

§  Dilation of a vertical feature in the reservoir and lower caprock [Davis 1983, Vasco 2010]

[not  to  scale]  

Seismic velocity anomalies §  Velocity pulldowns observed

above reservoir units

§  Not visible in main caprock units

Comparison of InSAR and seismic

421000 422000 423000

3226000

3227000

3228000

Easting, m

Nor

thin

g, m

NS1959, UTM 31N

Above C10.3C10.3 IntervalC10.2 Interval

KB−5

Velocity Anomaly(Seismic Interpretation)

InSARMarch 2010

KB−502

Ran

ge C

hang

e, m

m

0

2

4

6

8

10

12

14

16

18

20

Hypotheses to explain monitoring observations

Table 1: Plausible hypotheses to explain available monitoring observations of the lower caprock. Combinations ofthese mechanisms are also possible.

No. Mechanism Description Evidence

I Reservoir-only All observations are consistent with pressure and saturationcontained in the reservoir interval.

Weak

II Fault(s) The wells intersect one or more pre-existing faults providing avertical migration pathway.

Weak

III Hydrofracture Injection pressures have created new fracture pathways,through tensile hydrofracture.

Strong

IV Pre-fractured The lower caprock contains pre-existing fractures that are in-trinsically permeable, or re-activated by pressure and/or disso-lution.

Moderate

most visible to the southeast of the injector—near the gas/water contact—but the lineation intersects KB- 99

503 and is parallel to the anomaly at KB-502. KB-501 was not covered by the 2009 survey and therefore 100

could not be analyzed. This second anomaly suggests that at least two—and maybe all three—injectors are 101

behaving similarly. A subsequent analysis of two-component X-Band InSAR data by Rucci et al. (2013) 102

also suggests that horizontal deformations above all three injectors are consistent with vertical dilation zones 103

in the lower caprock. 104

It is unclear at this point if the observed velocity changes are caused by pressure, saturation, or mechan- 105

ical effects. At the time of the 2009 survey, KB-502 had been shut-in for approximately two years, and the 106

reservoir pressure had nearly returned to background. This suggests that the velocity anomalies are more 107

likely to be a saturation or mechanical effect. 108

These field observations all provide indirect indications that fluids may have migrated vertically, but 109

none is conclusive. A variety of hypotheses have therefore been put forward to explain these observations. 110

Plausible mechanisms are summarized in Table 1, along with an evaluation of the evidence in their favor. 111

The remainder of this paper examines these mechanisms in greater detail and describes the supporting and 112

contradictory evidence. Note that these mechanisms are not mutually exclusive (except for I) and more 113

than one may have occurred at the site. For example, injection pressures could have hydrofractured the 114

lower caprock by extending and coalescing pre-existing fractures (combining III and IV). Finally, much of 115

the analysis has focused on vertical propagation upward. For many of the proposed mechanisms, however, 116

there are physical grounds to expect that fluids could also migrate downwards into the Devonian units. For 117

obvious reasons, however, upward movement presents a greater concern with respect to storage integrity. 118

8

[White  et  al.  2013]  

Hydrofracture hypothesis

§  Explains narrow, linear features observed in seismic and InSAR response.

§  Features run perpendicular to minimum in situ stress, and parallel to one another.

§  Large uncertainties in LOT and FIT data, but injection pressures could have exceeded fracture gradient.

§  Injectivity analysis and microseismic show indications of fracturing behavior [Oye et al 2012].

0

100

200

300

400

500

1 1.2 1.4 1.6 1.8 2

He

igh

t a

bo

ve C

10

.2,

m

Equivalent Mud Weight, sg

LOT, C20

FIT, C20

LOT, C15

FIT, C10.3

SRT, C10.2

Hot Shale

Unstable Zone

C10.3

C10.2

Pre-existing fractures likely played an important role

§  Inferred stress regime at site is strike-slip (vertical stress is intermediate).

§  Pre-existing fractures well oriented for tensile opening and shear.

§  Could also extend and coalesce through hydrofracture and/or hydroshear.

§  Extensive fracture characterization presented in [Iding & Ringrose 2010].

15 10 5 0 5 10 15

W E

S

N

KB-10

Fracture  strikes  observed  in  offset  well  kb-­‐10.      Dips  typically  within  20°  of  verGcal.  

Stochastic inversion of InSAR data at kb-502

§  Attempt to estimate probability that linear feature has reached a certain height, using InSAR data alone.

§  Suggests moderate probability it has reached the Hot Shale, low probability it has exceeded H.U.C.

§  Results independent but consistent with seismic observations of anomaly, which disappears above the Hot Shale.

§  No monitoring data suggests the storage integrity has been compromised.

C10.2  

G=0.3-­‐2.0  Gpa  

G=2.0-­‐7.0  Gpa  

Hercynian  Uncomformity  

Hot  Shale  

[Ramirez  et  al.  2013]  

Lessons Learned

§  Major risks often stem from uncertainty in formation properties. Co-locating multiple operations allows site characterization to be leveraged.

§  It is useful to deploy multiple, independent monitoring tools. Interpretation of any one data set can be ambiguous, but together they form a clearer picture.

§  The redundant nature of the seals at In Salah make it very robust, even if unexpected events occur. New CCS sites should prioritize this redundancy.

Organization Chart

Carbon Fuel Cycles (Roger Aines)

Carbon Management (Susan Carroll)

LLNL Carbon Sequestration

Program

Task 1. Active Reservoir

Management

Task 2. In Salah

Task 3. China

Task 4. Snovit

Task 5. Carbonates

Technical Staff

Wolery Buscheck,

Aines

McNab, Chiaramonte, Ezzedine, Hao, Foxall

Ramirez, White

Friedmann

Chiaramonte, White, Hao, Trainor-Guitton

Carroll, Hao, Smith

Expertise

Experimental and Theoretical Geochemistry

Subsurface Hydrology

Computational Geomechanics

Seismology

Structural Geology

Gantt Chart

§  Tasks 2.1, 2.2, and 2.4 were completed on schedule.

§  Task 2.3 effort was shifted to other tasks due to delays in receiving the microseismic data.

§  Remaining project funds are being devoted to final reporting and peer-reviewed publications.

Task FY2011 FY2012 FY20132.1 Multiphase.flow.and.hydromechanical.modeling ! ! !2.2 Stochastic.inversion ! ! !2.3 Induced.microseismicity ! !2.4 Shallow.aquifer.geochemistry ! ! !

key:completeon5schedulecancelled!5milestone

Bibliography

§  In preparation or review

¡  J.A. White et al., “Geomechanical behavior of the reservoir/caprock system at the In Salah CO2 storage project”, (under review by operator).

¡  S. Ezzedine et al., “Assessing hydraulic fracturing of porous fractured media reservoirs: Application to In Salah”, (in preparation)

¡  A. Ramirez et al., “Stochastic inversion of InSAR data to detect penetration into the lower caprock at In Salah”, (in preparation).

§  Journal publications

¡  A.K. Karamalidis, S. Torres, A.J. Hakala, H. Shao, K.J. Cantrell, and S.A. Carroll. “Trace metal source terms in carbon sequestration environments.” Environmental Science and Technology 2012. doi:10.1021/es304832m

¡  S.A. Carroll, W.W. McNab, S. Torres.  “Experimental study of cement – sandstone/shale – brine – CO2 interactions”.  Geochemical Transactions 2011; 12:9 doi:10.1186/1467-4866-12-9.

¡  J.P. Morris, Y. Hao, W. Foxall, and W. McNab. “A study of injection-induced mechanical deformation at the In Salah CO2 storage project.” Int. J. Greenhouse Gas Control 2011; 5:2 doi 10.1016/j/ijgcc.2010.10.004

§  Numerous conference proceedings and abstracts.