Long term safety of geological co2 storage: lessons from Bravo Dome Natural CO2 reservoir - Marc Hesse, University of Texas at Austin, at UKCCSRC specialist meeting Flow and Transport for CO2 Storage, 29-30 October 2015

1. Long-term safety of geological CO2 storage:
Lessons from Bravo Dome Natural CO2 reservoir
Marc A. Hesse
Department of Geological Sciences
Institute for Computational Engineering & Sciences
October 29, 2015
Marc A. Hesse UKCCSRC Workshop October 29, 2015 1 / 40

2. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 2 / 40

3. Acknowledgements
Funding:
National Science Foundation - Hydrologic Sciences
Department of Energy - Basic Energy Sciences
Energy Frontier Research Center:
Center for Frontiers in Subsurface Energy Security
Bravo Dome collaborators:
Kiran Sataye, Daria Ahkbari, Kimberly Lankford, Martin
Cassidy, Toti Larson, Dani Stoeckli, Changli Yuan, Gary
Pope, OXY Bravo Dome team
Papers:
Sathaye, Hesse, Cassidy & Stockli (2014) PNAS
Sathaye, Larson, & Hesse (201X) EPSL Ahkbari & Hesse
(201X) in prep
Marc A. Hesse UKCCSRC Workshop October 29, 2015 3 / 40

4. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 4 / 40

5. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 5 / 40

6. Trapping contribution and time-scales
IPCC special report Reservoir simulation Theoretical analysis
100
101
102
103
104
100%
80%
60%
40%
20%
0%
FractionofCO2
trapped
Time since injection [yrs]
free CO2
solubility trapping
residual trapping
mineral trapping
100%
80%
60%
40%
20%
0%
101
102
103
104
Time since injection [yrs]
FractionofCO2
trapped
free CO2
solubility trapping
residual trapping
mineral trapping
100%
80%
60%
40%
20%
0%
1 3 9
Injection periods [-]
FractionofCO2
trapped
solubility trapping
residual trapping
free CO2
Benson et al. (2005)
IPCC Special Report
Kumar et al. (2005)
SPE Journal, 10(3)
MacMinn et al. (2011)
J. Fluid Mech., 688
Marc A. Hesse UKCCSRC Workshop October 29, 2015 6 / 40

7. Trapping contribution and time-scales
IPCC special report Reservoir simulation Theoretical analysis
100
101
102
103
104
100%
80%
60%
40%
20%
0%
FractionofCO2
trapped
Time since injection [yrs]
free CO2
solubility trapping
residual trapping
mineral trapping
100%
80%
60%
40%
20%
0%
101
102
103
104
Time since injection [yrs]
FractionofCO2
trapped
free CO2
solubility trapping
residual trapping
mineral trapping
100%
80%
60%
40%
20%
0%
1 3 9
Injection periods [-]
FractionofCO2
trapped
solubility trapping
residual trapping
free CO2
Benson et al. (2005)
IPCC Special Report
Kumar et al. (2005)
SPE Journal, 10(3)
MacMinn et al. (2011)
J. Fluid Mech., 688
Constrain trapping rates at Bravo Dome using field observations!
Marc A. Hesse UKCCSRC Workshop October 29, 2015 6 / 40

8. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 7 / 40

9. Bravo Dome natural gas field, New Mexico
Marc A. Hesse UKCCSRC Workshop October 29, 2015 8 / 40

10. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

11. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
20 km
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

12. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
Gas-water contact: 1700 km2
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

13. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
Gas-water contact: 1700 km2
Reserves: 22 tcf (10 tcf)
Largest CO2 field.
Top 20 natural gas fields.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

14. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
Gas-water contact: 1700 km2
Reserves: 22 tcf (10 tcf)
Largest CO2 field.
Top 20 natural gas fields.
Essentially pure CO2
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

15. Introduction Bravo Dome, NM
The numbers:
Area: 3600 km2
Gas-water contact: 1700 km2
Reserves: 22 tcf (10 tcf)
Largest CO2 field.
Top 20 natural gas fields.
Essentially pure CO2
Origin: volcanic gas
(very high 3
He/4
He)
Marc A. Hesse UKCCSRC Workshop October 29, 2015 9 / 40

16. Data available at Bravo Dome, NM
788 wells
150 wells with digitized logs
42 cored wells
10 wells with stratigraphic logs
18 wells with noble gas/isotope data
3645 permeability and porosity
measurements
21 drainage capillary pressure curves
40 2D seismic lines
Best data set to constrain the magnitude and rate of solubility trapping.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 10 / 40

17. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 11 / 40

18. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 12 / 40

19. Estimating dissolution from gas composition
Convective dissolution of CO2
CO2CO2
He He
CO2 CO2
Marc A. Hesse UKCCSRC Workshop October 29, 2015 13 / 40

20. Estimating dissolution from gas composition
Convective dissolution of CO2 CO2/3
He-ratio in the gas
CO2CO2
He He
CO2 CO2
0 5 10 15 20 25 30 35
0
2
4
6
8
10
12
14
16
18
time [hrs]
CO2
/Heingas[mol/mol]
Fraction dissolved: F = 1 −
[CO2/He]final
[CO2/He]initial
≈ 1 − 2
16 ≈ 0.9
Marc A. Hesse UKCCSRC Workshop October 29, 2015 13 / 40

21. Mapping geochemistry into the reservoir
Gas geochemistry:
Gilfillan et al. (2009) Nature, 458
Lollar & Ballentine (2009) Nature Geosci, 2(8)
Cassidy (2006) PhD Thesis U. Houston
Marc A. Hesse UKCCSRC Workshop October 29, 2015 14 / 40

22. Mapping geochemistry into the reservoir
Gas geochemistry: Compositional variation in the reservoir
2.5
3
3.5
4
4.5
5
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
CO2
/3
H109
[-]
8 MPa
Gilfillan et al. (2009) Nature, 458
Lollar & Ballentine (2009) Nature Geosci, 2(8)
Cassidy (2006) PhD Thesis U. Houston
Marc A. Hesse UKCCSRC Workshop October 29, 2015 14 / 40

23. Mapping geochemistry into the reservoir
Gas geochemistry: Compositional variation in the reservoir
10%
20%
30%
40%
50%
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
60%
0%
localfractionofgasdissolved
Gilfillan et al. (2009) Nature, 458
Lollar & Ballentine (2009) Nature Geosci, 2(8)
Cassidy (2006) PhD Thesis U. Houston
Marc A. Hesse UKCCSRC Workshop October 29, 2015 14 / 40

24. Gas mass per area: m = ¯φ ¯Sρ(¯p)h
Thickness
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
20
40
60
80
100
120
thicknessofgascolumn:h[m]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 15 / 40

25. Gas mass per area: m = ¯φ ¯Sρ(¯p)h
Thickness Volume fraction
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
20
40
60
80
100
120
thicknessofgascolumn:h[m]
0
10
20
30
40
50
60
70
Northing(km)
4%
6%
8%
10%
12%
14%
16%
0 10 20 30 40 50 60 70
Easting (km)
gasvolumefraction:φS
Marc A. Hesse UKCCSRC Workshop October 29, 2015 15 / 40

26. Gas mass per area: m = ¯φ ¯Sρ(¯p)h
Thickness Volume fraction Density
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
20
40
60
80
100
120
thicknessofgascolumn:h[m]
0
10
20
30
40
50
60
70
Northing(km)
4%
6%
8%
10%
12%
14%
16%
0 10 20 30 40 50 60 70
Easting (km)
gasvolumefraction:φS
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
gasdensity[kg/m3
]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 15 / 40

27. Gas mass per area: m = ¯φ ¯Sρ(¯p)h
Thickness Volume fraction Density Mass
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
20
40
60
80
100
120
thicknessofgascolumn:h[m]
0
10
20
30
40
50
60
70
Northing(km)
4%
6%
8%
10%
12%
14%
16%
0 10 20 30 40 50 60 70
Easting (km)
gasvolumefraction:φS
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
gasdensity[kg/m3
]
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
900
1000
1100
0
gasmassperunitarea[kg/m2
]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 15 / 40

28. Gas mass per area: m = ¯φ ¯Sρ(¯p)h
Thickness Volume fraction Density Mass
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
20
40
60
80
100
120
thicknessofgascolumn:h[m]
0
10
20
30
40
50
60
70
Northing(km)
4%
6%
8%
10%
12%
14%
16%
0 10 20 30 40 50 60 70
Easting (km)
gasvolumefraction:φS
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
gasdensity[kg/m3
]
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
900
1000
1100
0
gasmassperunitarea[kg/m2
]
Large spatial variations that need to be accounted for in mass balance.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 15 / 40

29. Estimate of the local change in mass: ∆m
∆M = ∆m dxdy ≈ (1/F − 1) mf dxdy.
Mass/area: mf Fraction dissolved: F
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
900
1000
1100
0
gasmassperunitarea[kg/m2
]
10%
20%
30%
40%
50%
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
60%
0%
localfractionofgasdissolvedMarc A. Hesse UKCCSRC Workshop October 29, 2015 16 / 40

30. Estimate of the local change in mass: ∆m
∆M = ∆m dxdy ≈ (1/F − 1) mf dxdy.
Mass/area: mf Fraction dissolved: F Change in mass, ∆m
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
900
1000
1100
0
gasmassperunitarea[kg/m2
]
10%
20%
30%
40%
50%
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
60%
0%
localfractionofgasdissolved
50
100
150
200
250
300
350
400
450
0
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
masslossperunitarea[kg/m2
]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 16 / 40

31. Estimate of the local change in mass: ∆m
∆M = ∆m dxdy ≈ (1/F − 1) mf dxdy.
Mass/area: mf Fraction dissolved: F Change in mass, ∆m
0 10 20 30 40 50 60 70
0
10
20
30
40
50
60
70
Easting (km)
Northing(km)
100
200
300
400
500
600
700
800
900
1000
1100
0
gasmassperunitarea[kg/m2
]
10%
20%
30%
40%
50%
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
60%
0%
localfractionofgasdissolved
50
100
150
200
250
300
350
400
450
0
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
masslossperunitarea[kg/m2
]
As expected, mf is low where F is high → global fraction dissolved is less!
Marc A. Hesse UKCCSRC Workshop October 29, 2015 16 / 40

32. Magnitude of CO2 dissolution at Bravo Dome
1 Mass of gas dissolved at Bravo Dome:
∆M = 366 ± 122 MtCO2.
Equivalent to 65 years of emissions
from US coal power plant.
2 Total mass of CO2 emplaced at Bravo
Dome is Mt = 1.6 ± 0.7GtCO2.
Equivalent to annual global volcanic
CO2 emissions.
3 At Bravo Dome only 22%±7% of
the emplaced CO2 have dissolved.
Much less than the maximum local
dissolution in NE.
free CO2
77%
dissolved
CO2
23%
Marc A. Hesse UKCCSRC Workshop October 29, 2015 17 / 40

33. Magnitude of CO2 dissolution at Bravo Dome
1 Mass of gas dissolved at Bravo Dome:
∆M = 366 ± 122 MtCO2.
Equivalent to 65 years of emissions
from US coal power plant.
2 Total mass of CO2 emplaced at Bravo
Dome is Mt = 1.6 ± 0.7GtCO2.
Equivalent to annual global volcanic
CO2 emissions.
3 At Bravo Dome only 22%±7% of
the emplaced CO2 have dissolved.
Much less than the maximum local
dissolution in NE.
free CO2
77%
dissolved
CO2
23%
Uncertainty is mainly due to variations in height of gas column!
Marc A. Hesse UKCCSRC Workshop October 29, 2015 17 / 40

34. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 18 / 40

35. Stratigraphic architecture of reservoir
Porosity and permeability
10-2
10-1
100
101
102
103
0
100
200
[mD]
n = 3546
0 0.1 0.2 0.3
0
100
200
[-]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 19 / 40

36. Stratigraphic architecture of reservoir
Porosity and permeability
10-2
10-1
100
101
102
103
0
100
200
[mD]
n = 3546
0 0.1 0.2 0.3
0
100
200
[-]
sandsilt
Marc A. Hesse UKCCSRC Workshop October 29, 2015 19 / 40

37. Stratigraphic architecture of reservoir
Porosity and permeability
10-2
10-1
100
101
102
103
0
100
200
[mD]
n = 3546
0 0.1 0.2 0.3
0
100
200
[-]
42 mD
Marc A. Hesse UKCCSRC Workshop October 29, 2015 19 / 40

38. Stratigraphic architecture of reservoir
Porosity and permeability Capillary entry pressure
10-2
10-1
100
101
102
103
0
100
200
[mD]
n = 3546
0 0.1 0.2 0.3
0
100
200
[-]
42 mD
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.5
1.0
1.5
2.0
2.5
[MPa]
[-]
siltstone
sandstone
Marc A. Hesse UKCCSRC Workshop October 29, 2015 19 / 40

39. Stratigraphic architecture of reservoir
Porosity and permeability Capillary entry pressure
10-2
10-1
100
101
102
103
0
100
200
[mD]
n = 3546
0 0.1 0.2 0.3
0
100
200
[-]
42 mD
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.5
1.0
1.5
2.0
2.5
[MPa]
[-]
siltstone
sandstone
High capillary entry pressure prevents CO2 entry into the siltstone.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 19 / 40

40. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

41. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

42. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

43. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

44. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

45. Dissolution into residual brine during emplacement
0 0.1 0.25
695
705
715
725
735
745
φ, φg
[-]
silt}
} sand
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
anhydrite
0 20 40 60 80 100 120
0
0.2
0.4
0.6
0.8
1
1.2
Pressure [bar]
CO2solubility[
mol
kg
]
Bravo Dome Measurments
Duan et al. (2003): pure water
Duan et al. (2003): 2 molal NaCl
Easting (km)
Northing(km)
0 25 50 75
0
25
50
75
0
50
100
150
CO2(aq)
[kg/m2
]
Marc A. Hesse UKCCSRC Workshop October 29, 2015 20 / 40

46. How much dissolved during emplacement
Main reservoir segment Map of Bravo Dome: NE reservoir segment:
residual
brine 53%
aquifer 47%
10%
20%
30%
40%
50%
0 10 20 30 40 50 60 70
Easting (km)
0
10
20
30
40
50
60
70
Northing(km)
60%
0%
localfractionofgasdissolved
residual
brine 14%
aquifer 86%
1 Significant amounts dissolved into ’residual brine’ during emplacement.
Highlights positive effect of heterogeneity on dissolution!
2 Significant amounts dissolved into underlying aquifer after emplacement.
Provides field evidence for enhanced dissolution due to brine flow.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 21 / 40

47. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 22 / 40

48. CO2 emplacement and regional volcanism
Distribution of regional volcanism Age of regional volcanism
[MPa]
2 4 6 8 10 12 14
−60 −40 −20 0 20 40 60 80
20
40
60
80
100
120
140
160
1.7Ma−56ka
9Ma−2.2Ma
easting [km]
northing[km]
Texas
Oklahoma
Colorado
T1
0
95
Folsom SiteFolsom Site
Capulin volcanoCapulin volcano
New Mexico
volcanic ages:
T2
Assumed age of Bravo Dome is 10ka.
Three major volcanic phases:
1 Raton phase: 9.0 - 3.5 Ma
2 Clayton phase: 3.0 -2.25 Ma
3 Capulin phase: 1.7 - 0.04 Ma
Independent estimate of CO2 age!
Stroud (1996) M.S. Thesis, NM Tech
Marc A. Hesse UKCCSRC Workshop October 29, 2015 23 / 40

49. Dating CO2 emplacment with thermochronology
Core sample with Apatite crystal
Marc A. Hesse UKCCSRC Workshop October 29, 2015 24 / 40

50. Dating CO2 emplacment with thermochronology
Core sample with Apatite crystal (U-Th)/He thermochronology
Apatite accumulates He from radioactive decay below T = 75◦
C.
Current reservoir conditions T = 35◦
C → heating by ∆T ≈ 40◦
C
Marc A. Hesse UKCCSRC Workshop October 29, 2015 24 / 40

51. Dating CO2 emplacment with thermochronology
Core sample with Apatite crystal (U-Th)/He thermochronology
Apatite accumulates He from radioactive decay below T = 75◦
C.
Current reservoir conditions T = 35◦
C → heating by ∆T ≈ 40◦
C
Hot volcanic CO2 entered Bravo Dome 1.2-1.5 Ma ago.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 24 / 40

52. Estimate IPCC–diagram for Bravo Dome
100
101
102
103
104
100%
80%
60%
40%
20%
0%
FractionofCO2
trapped
Time since injection [yrs]
free CO2
solubility trapping
residual trapping
mineral trapping
Marc A. Hesse UKCCSRC Workshop October 29, 2015 25 / 40

53. Estimate IPCC–diagram for Bravo Dome
Bravo Dome
100%
80%
60%
40%
20%
0%
FractionofCO2
trapped
100
101
102
103
104
Time since emplacement [yrs]
105
106 107
free CO2
solubility trapping
Marc A. Hesse UKCCSRC Workshop October 29, 2015 25 / 40

54. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 26 / 40

55. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 27 / 40

56. Pressures gradients at Bravo Dome
[MPa]
2 4 6 8 10 12 14
−60 −40 −20 0 20 40 60 80
20
40
60
80
100
1.7Ma−56ka
9Ma−2.2Ma
easting [km]
northing[km]
Texas
0
95
volcanic ages:
?
?
?
?
?
?
Is the reservoir still filling?
If not, why didn’t the pressure gradient relax?
Marc A. Hesse UKCCSRC Workshop October 29, 2015 28 / 40

57. Sub-hydrostatic gas pressures at Bravo Dome
Bravo Dome gas pressure
0 2 4 6 8 10
600
650
700
750
800
850
900
Gas Pressure (MPa)
Depth(m)
A
B
C
D
E
F
ρwg
ρgg
pe
Marc A. Hesse UKCCSRC Workshop October 29, 2015 29 / 40

58. Sub-hydrostatic gas pressures at Bravo Dome
Bravo Dome gas pressure Pressure compartments
0 2 4 6 8 10
600
650
700
750
800
850
900
Gas Pressure (MPa)
Depth(m)
A
B
C
D
E
F
ρwg
ρgg
pe
103103.2103.4103.6103.8
35.6
35.8
36
36.2
36.4
Longitude (°W)
Latitude(°N)
A
BC
DE
F
S
T
Marc A. Hesse UKCCSRC Workshop October 29, 2015 29 / 40

59. Stratigraphic controls on compartmentalization
Pressure compartments
103103.2103.4103.6103.8
35.6
35.8
36
36.2
36.4
Longitude (°W)
Latitude(°N)
A
BC
DE
F
S
T
Marc A. Hesse UKCCSRC Workshop October 29, 2015 30 / 40

60. Stratigraphic controls on compartmentalization
Pressure compartments Gas volume fraction ˜sand fraction
103103.2103.4103.6103.8
35.6
35.8
36
36.2
36.4
Longitude (°W)
Latitude(°N)
A
BC
DE
F
S
T
0
10
20
30
40
50
60
70
Northing(km)
4%
6%
8%
10%
12%
14%
16%
0 10 20 30 40 50 60 70
Easting (km)
gasvolumefraction:φS
Marc A. Hesse UKCCSRC Workshop October 29, 2015 30 / 40

61. Stratigraphic controls on compartmentalization
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
compartment 1
compartment 2
compartment 3
Marc A. Hesse UKCCSRC Workshop October 29, 2015 31 / 40

62. Stratigraphic controls on compartmentalization
B 5 15 25 35 45 55 65 B’
500
600
700
800
900
granitic basement
brine
elevation[m]
source
distance along cross-section [km]
compartment 1
compartment 2
compartment 3
CO2 is stored in a number of closed compartments?
Marc A. Hesse UKCCSRC Workshop October 29, 2015 31 / 40

63. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 32 / 40

64. Sub-hydrostatic gas pressures at Bravo Dome
14 ± 3%
5%
16%
Total Subhydrostatic Pressure = 6.3 MPa
Regional Subhydrostatic
Ogallala Depletion
Erosional Unloading
Cooling of Volcanic CO2
Dissolution of CO2
into Brine
Un-Explained
41 ± 30%
10 ± 5%
14 ± 4%
Marc A. Hesse UKCCSRC Workshop October 29, 2015 33 / 40

65. Sub-hydrostatic gas pressures at Bravo Dome
14 ± 3%
5%
16%
Total Subhydrostatic Pressure = 6.3 MPa
Regional Subhydrostatic
Ogallala Depletion
Erosional Unloading
Cooling of Volcanic CO2
Dissolution of CO2
into Brine
Un-Explained
41 ± 30%
10 ± 5%
14 ± 4%
250 300 350 400 450 500
0
2
4
6
8
10
12
Temperature (K)
Pressure(Mpa)
CO2 Isodensity Diagram
Dissolution Effect
∆P = 0.7 - 1.1 MPa
Marc A. Hesse UKCCSRC Workshop October 29, 2015 33 / 40

66. Regional underpressure
33˚ N
34˚ N
35˚ N
36˚ N
37˚ N
38˚ N
Latitude
Langitude
100˚ W101˚ W102˚ W103˚ W104˚ W105˚ W106˚ W
A A’
Marc A. Hesse UKCCSRC Workshop October 29, 2015 34 / 40

67. Regional underpressure
33˚ N
34˚ N
35˚ N
36˚ N
37˚ N
38˚ N
Latitude
Langitude
100˚ W101˚ W102˚ W103˚ W104˚ W105˚ W106˚ W
A A’
Elevation(ft)
-6000
-4000
-2000
0
2000
4000
6000
100˚ W101˚ W102˚ W103˚ W104˚ W
Langitude
A’A
Precambrian
Basement
TXNM
Anadarko
Dalhart
Basin
Wolfcampion
Marc A. Hesse UKCCSRC Workshop October 29, 2015 34 / 40

68. Underpressure due to regional evaporite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 35 / 40

69. Underpressure due to regional evaporite
Permian
Evaporite
Marc A. Hesse UKCCSRC Workshop October 29, 2015 35 / 40

70. Underpressure is normal in natural CO2 reservoirs
Gas Pressure (MPa)
Depth(m)
0
4000
3000
2000
1000
0 302010
SJ E
DM
MD
KD
GC
MC
MD
L
GC
KD
MC
GC L
MD
SJ E
DM
B1
B5
B4
B2
B3
BD
DM: Des Moines
E: Estancia
GC: Gordon Creek
KD: Kevin Dome
L: Lisbon
MC: Mc Callum
MD: McElmo Dome
SJ: St. Johns
B1: Denver Basin
B2: Anadarko Basin
B3: Arkoma Basin
B4 Palo Duro Basin
B5: San Juan Basin
ρw g
Marc A. Hesse UKCCSRC Workshop October 29, 2015 36 / 40

71. Outline
1 Introduction
Motivation
Bravo Dome natural CO2 field in New Mexico
2 Dissolution trapping at Bravo Dome
Magnitude of CO2 dissolution
Mechanism of solubility trapping at Bravo Dome
Rate of CO2 dissolution
3 Pressures in natural CO2 reservoirs
Reservoir compartmentalization
Origins of subhydrostatic pressures
4 Implications for geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 37 / 40

72. Summary and conclusion
Natural analogs for geological CO2 storage
1 Large amounts of data are freely available.
2 Provide constraints in long-term fate of geological CO2 storage
Marc A. Hesse UKCCSRC Workshop October 29, 2015 38 / 40

73. Summary and conclusion
Natural analogs for geological CO2 storage
1 Large amounts of data are freely available.
2 Provide constraints in long-term fate of geological CO2 storage
Dissolution at Bravo Dome
1 Estimate that 366 MtCO2 have dissolved.
2 50% dissolves into residual brine during emplacement.
3 50% dissolves after emplacement into aquifer.
4 Emplacement of CO2 1.2-1.4 Ma ago.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 38 / 40

74. Summary and conclusion
Natural analogs for geological CO2 storage
1 Large amounts of data are freely available.
2 Provide constraints in long-term fate of geological CO2 storage
Dissolution at Bravo Dome
1 Estimate that 366 MtCO2 have dissolved.
2 50% dissolves into residual brine during emplacement.
3 50% dissolves after emplacement into aquifer.
4 Emplacement of CO2 1.2-1.4 Ma ago.
Pressures at Bravo Dome
1 Pressure is significantly below hydrostatic (common).
2 CO2 dissolution can reduce pressure in compartmentalized reservoir.
3 Permian evaporites are associated with large regional underpressure.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 38 / 40

75. Implications for CO2 storage
Trapping and safety
1 Structural trapping contained large volume over millenial timescales.
2 Dissolution trapping is slower then expected.
3 Dissolution trapping is nice, but not strictly necessary.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 39 / 40

76. Implications for CO2 storage
Trapping and safety
1 Structural trapping contained large volume over millenial timescales.
2 Dissolution trapping is slower then expected.
3 Dissolution trapping is nice, but not strictly necessary.
Geological CO2 storage on a scale large enough to matter?
1 Sleipner is an example of successful storage in an optimal formation.
2 Bravo Dome is an example if successful storage in a formation
that would not be considered optimal.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 39 / 40

77. Implications for CO2 storage
Trapping and safety
1 Structural trapping contained large volume over millenial timescales.
2 Dissolution trapping is slower then expected.
3 Dissolution trapping is nice, but not strictly necessary.
Geological CO2 storage on a scale large enough to matter?
1 Sleipner is an example of successful storage in an optimal formation.
2 Bravo Dome is an example if successful storage in a formation
that would not be considered optimal.
Low-pem & low-pressure formations as CO2 storage targets
1 Previously considered for hazardous waste injection.
2 CO2 is less mobile than in high perm formations.
3 Inject large amounts before reaching hydrostatic pressure.
4 CO2 dissolution reduces pressure over time.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 39 / 40

78. Implications for CO2 storage
Trapping and safety
1 Structural trapping contained large volume over millenial timescales.
2 Dissolution trapping is slower then expected.
3 Dissolution trapping is nice, but not strictly necessary.
Geological CO2 storage on a scale large enough to matter?
1 Sleipner is an example of successful storage in an optimal formation.
2 Bravo Dome is an example if successful storage in a formation
that would not be considered optimal.
Low-pem & low-pressure formations as CO2 storage targets
1 Previously considered for hazardous waste injection.
2 CO2 is less mobile than in high perm formations.
3 Inject large amounts before reaching hydrostatic pressure.
4 CO2 dissolution reduces pressure over time.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 39 / 40

79. Thank you for your attention.
Marc A. Hesse UKCCSRC Workshop October 29, 2015 40 / 40