3/07/2012

CCS
Workshop – Ensuring safety toward public acceptanceth18January 2012

Dr John Bradshaw

Chief Executive Officer
CO2 Geological Storage Solutions (CGSS) &Bradshaw Geoscience Consultants
www.cgss.com.au

GEOLOGICAL STORAGE OF CO2:“PRACTICALITIES” - ISSUES, RISKS AND
UNCERTAINTIES ASSOCIATED WITH SITE
SELECTIONOUTLINE
Storagecapacity
CO2 density
rock volume ( pore vs invaded )efficiency

Storage Ready
Depositional environments
Injectivity
Reservoir & Seal prediction? Pressure build up ?

1

3/07/2012

STORAGE CAPACITY? - BASICS

Volumetric (Capacity) EquationThe basic equation for volumetric estimationis:

MCO2 = RV * Ø * δ(CO2)
MCO2 = mass of CO2 stored in kilograms
RV = total reservoir rock volume in m3
Ø = total effective pore space (as a fraction)
δ(CO2) = the density of CO2 at the given reservoir
depth (pressure and temperature) in kg/m3.
Whilst capacity (volume) is important, injectivity(rate) is far more critical for site selection42

3/07/2012

World and Regional Storage Capacity Estimates

World - Koide 9 2
World - van de r Me e r 9 2
World - IEA 9 2
World - He ndriks a nd Blok 9 3World - He ndriks a nd Blok 9 4
World - IEA 9 4World - He ndriks 9 4
World - He ndriks & Blok 9 5World - Turke nburg 9 7
World - IPCC 0 1/ Arc 0 0World - ECO FY S & TNO - NITG 2 00 2
World - Brua nt 0 2
World 1 - GEOS EQWorld 2 - Be e cy & Kuuskra 0 1
World 3 - IEA
World - Doole y a nd Frie dma nWorld - ECO FYSWorld : 100 –200,000 GT

Europe - va n der Stra a te nEurope - Boe e t a l
NW Europe - Joule Re port
We ste rn Europe - Doole y amd Frie dma n
Ea ste rn Europe - Doole y a nd Frie dma n
Former Soviet Union - Doole y andCombine d Europe - Doole y a nd Frie dma n
We ste rn Europe - ECO FYS
Ea ste rn Europe - ECO FYS
Tota l Europe - ECO FYS

Europe :1 – 2449 GT

USA - Be rgma n & Winter(Mt Simon Sa ndstone (Ohio(Mt Simon Sa ndstone (MidWest USA
Mt Simon Sa ndstone
USA - Doole y a nd Frie dma n
US A - ECO FYS

USA : 2 – 3747 GT

ANCIENT HISTORY ?

Canada : 2 – 4000+ GT

Albe rta Ba sin (Ca na da ) - Tota lAlbe rta Ba sin (Ca na da ) - Viking Fmn
Cana da - Doole y a nd Frie dma nCa na da - ECO FYS

Australia : 4 – 740 GT

Austra lia - Bradsha w e t a l 2 00 2
Austra lia / NZ - Doole y a nd Frie dma n
O ce a nia - ECO FYS

01,00

0,0000,010GT CO20,00

000
1,0
1010

1Bradshaw, 2002

0

Japan : 0 – 80 GT

Japa n - ECO FYS
Japa n - Doole y a nd Frie dma n
Ja pa n10Study Location(Most estimates based on using surface area calculation)Storage Capacity estimates
Matched capacity:
Detailed matching of sources and sinks including supply
and reservoir performance assessment

Increasing
constraints of technical,legal, regulatory andcommercial certainty

Practical (Viable) capacity:
Applies economic and regulatory barriers torealistic capacity,

Effective (Realistic) capacity:
Applies technical cut off limits, technically
viable estimate, more pragmatic, actualsite / basin data

Theoretical capacity:
includes large volumes of“uneconomic” opportunities.
Approaches physical limitof pore rock volume ; unrealistic
and impractical estimate63

3/07/2012“ROCK IS KING”

Volumetric (Capacity) Equation
The basic equation for volumetric estimation is:

MCO2 = RV * Ø * δ(CO2)?

MCO2 = mass of CO2 stored in kilograms
RV = total reservoir rock volume in m3 (within
fairway – not whole basin)
Ø = total effective pore space (as a fraction)
δ(CO2) = the actual density of CO2 at the given
reservoir depth (pressure and temperature) in kg/m3.

84

3/07/2012

Temperature & Pressure
0204060

80100120140160

180200-500° Centigrade
0500

Depth mSS

10001500Temperature GradientTemperature Data
Ground Level

2000

Pressure Datum
Pressure Data

2500

Pressure Gradient

3000

3500

Pressure psi
4000
01000

2000

3000

4000

5000

6000

7000

Calculate temperature and pressure gradients from WCR’s•

Temperature gradient ~35°C through southern Bowen Basin•Pressure gradient ~1.4374 psi/m

9

Geothermal
Gradient
Variation

Detailed temperature
gradient map (° C / km)over southern andwestern Bowen Basin basin outline in red.

5

3/07/2012

CO2 Density
Under the normal range ofpressure/ temperature
conditions found in
sedimentary basins, thedensity of CO2 can varysignificantly
The precision of the CO2
density estimate depends
on the accuracy ofpressure and temperature
estimates.
CO2 density given two end-member basin
conditions: a hot fresh-water (red curve) a
cold saline-water basin (blue curve);
11
Eromanga Basin in (green curve)

So what is occurring with CO2 Density
Repeatedly authors are using default values
E.g. 600 to 700 kg/m3

Some, whilst also quoting geothermal
gradients

So let’s look at some real data &identify the issue63/07/2012

Density of CO2 & Factors that control Storage Capacity

FRESH
COLDHOTSALINE
COLD

40.2oC/KmFresh
Bow-Den

800 m

43.6o C/KmSalineBow -Den

1500 m38.8o C/Km
Fresh
Gal-Ero28 to 37o C/Km
Fresh
Surat
28 to 34.9o C/KmSalineBow (S)HOTSALINE

Australian Government : National Carbon Mapping & Infrastructure Plan
Monte Carlo Probabilistic Approach – Australian Basins
250 kg/m3

425 kg/m3

1000 mPorosity cutoff
depth of 2000 m

CO2 density given two end-member basin
conditions: a hot fresh-water (red curve) a
http://www.ret.gov.au/resources/Documents/cst/Eromanga-Basin.pdf
cold saline-water basin (blue curve);

So, these values
were notoncurve)
the curve of reality
Eromanga
Basinevenin (green73/07/2012

RISK and UNCERTAINTYRISK is that you are not
UNCERTAINTY iseven on the curve and haveestimating the “real” range
wrong shapeof input values• poor science,
P50• doing ourrushed, wrong
homeworkapproach,inconsistent tests
Lots ofmodelling withno data P90

P10

Message 1
Do your homework on CO2 density for your site,
and,avoid generic approaches
and, above all else;
look at your rocks and your data(“get your hands dirty”)

8

3/07/2012

WHAT ABOUT ESTIMATING THE
INVADED ROCK VOLUME?

Volumetric (Capacity) Equation
The equation for volumetric estimation is:

MCO2 = RV * Ø * δ(CO2)
MCO2 = mass of CO2 stored in kilograms
RV = total reservoir rock volume in m3 (withinfairway – not whole basin)
Ø = total effective pore space (as a fraction)
δ(CO2) = the actual density of CO2 at the given
reservoir depth (pressure and temperature) in kg/m3.

18

9

3/07/2012

Storage Area “Fairway”
1. Define “Fairway”
Extent of regional sealbase Jurassic unconformity
Widespread reservoir

Probable storage area
Reservoir quality
2. Calculate Areas &Reservoir Parameters
Drainage Area
Net pay zone
thickness
Average porosity

Sth Bowen Basin fairway map

Sth Bowen Basin drainage map

Must Map
Fairways“real” data
Stratigraphic
Pinchout “barrier to flow pressure build up- avoid”
Areas of “rough” heterogeneities –
could be good
Bounding Faults –“reactivate or lose
CO2 - avoid”

If want sensible
capacity numbers

19

Top of Structure –“final location”
Carbonate&wanttoBut what
proportion
understandof thetotal porerealprospectivty
volume will the CO2of therocks ?
actually“invade”
MUST
understand therocks and rockvolume that CO2
will “invade”

mudHigh Permeability
Sandstone
Streaks – “loseCO2 - avoid”

Structural Trapping
Residual Gas Trapping(+/- Dissolution etc)
Migration Assisted
Storage (MAS)

Migration
Pathway
Total Pore
Volume“invadedArea “drainagearea/volume”
cell”

Injection Location

10

3/07/2012

Volumetric (Capacity) Equation
So what does RV =MCO2 = RV * Ø * δ(CO2)
1. Entire golf course ?
From car park to course to golf club (19th hole)

2. Full extent of the fairway ?
Including out of bounds?

3. Or just the areas and points the golf balls travels

along and lands in? – i.e. CO2 migration pathway

And let’s
Pressure
not forgetwill likely
whatreachhappens
all with therdhydrodynamically
3 dimension -connected
thickness (depth)
areas

21

MAS efficiency factor
Unit Thickness (m)% of Reservoir invaded

100m thick reservoir
15m thick plume= 16% of reservoir
actually accessible

Must make allowancefor the % of reservoir
actually invaded by
the migrating CO2
plume

CO2 plume will not
invade entire reservoir
22113/07/2012

CO2 Emissions

CH4 Production

100,0006349

10,000(log scale)Million Tonnes & TCF CO2

How big does Storage have to be ?
500

1,000

100
40100

22.3

5101 TCF
Gas field is a “big” 1.3gas field
1Mt CO2
TCF CO2/CH4Aust.
LSPS /yr

USA
LSPS /yr

Worldtotal
CO2
eq / yr

260
52000
4027000
500

Aust.
USA World Worldgas
Gasgasres. &prod'n prod'n prod'n prod'd/ yr/ yr/ yrgas
(tot)
1.3

22.31006349

Due to scale of the volume of CO2,
and the delay for gas field depletion,saline reservoirs are the principal
targetImportance of Saline Reservoirs

123/07/2012

Message 2
Think about the actual rock volume and the rocks that
CO2 will invade,and,the importance of MAS to trap large volumes of CO2

STORAGE EFFICIENCY (SE) PITFALLS?

13

3/07/2012

Volumetric (Capacity) Equation
So what about Storage Efficiency factors

MCO2 = RV * Ø * δ(CO2) * SEMany authors now use SE to allow for a range ofgeological considerations – not examined at scaleOften use between 1% and 6% to get quick
regional estimates

CGSS does not use them – why?
27

CGSS method vs Storage Efficiency

MCO2 = RV * Ø *δ(CO2) * SE
Note: The thicker the reservoir, the larger the discrepancy…. and then there are the pressure impacts

14

3/07/2012

Message 3
Estimate the real capacity by mapping the migration
pathway (fairways),and,don’t rely on efficiency factors(Usually done in detail with reservoir modelling oncea specific site is chosen)Wrong Question:
Better to ask about cost …
& if Car park, Basin, Country or the World?
1. What is the price on CO2 ?
2. How far are you prepared to transport it?
3. How many wells do I need / afford
SO JOHN, ……..
WHAT IS “THE BEST” CAPACITY ESTIMATE ?

15

3/07/2012…… to reliably estimate the cost weneed to understand the potential
storage site(“Storage Ready”)
SO TO GET TO CAPACITY WE NEEDTO UNDERSTAND THE COST

What is Storage Ready? (CGSS definition)
The processes and outcomes from identifying, proving
and securing a geological storage site that is capableof having industrial quantities of CO2 injected andstored in the deep subsurface on a sustainable basis,
whilst maintaining high geological integrity in thegeological structures and formations both during andafter the injection and storage period.
… ideally a risk assessment should establish
BUT :benchmarks
like theseto proving
measureagainstdoes notdescribe the processes
involved
a storage
site, …
does not elaborate on levels of proof and certainty that may be required,
does not express the conceptual nature of the understanding of thegeological attributes of the deep subsurface, anddoes not document the actual impacts that the geological characteristics ofthe deep subsurface may have on a site being proven to be storage ready.
3216

3/07/2012

Zerogen objectives for Risk and Uncertainty
Test 1. Containment & Capacity
a P50 level of confidence in secure containment of 60
Mt.

Test 2. Capacity & Injectivity
a P50 level of confidence in injection of 2 Mt pa
sustained over 30 years.

Test 3. Injectivity (esp. well count)a P50 level of confidence in life-cycle CTS unit costs ofless than A$50/t for carbon transported and stored.
Zerogen GHGT10 - 2010

“Storage Ready” could take 5 - 10 years

173/07/2012

Various Geoscience disciplines:

Geochemistry
Hydrodynamics
Geomechanics
Petrography
Reservoir simulations
Stratigraphy
Geophysics

Site Characterisation & Selection Work Flow
Data Acquisition& Analysis

Modelling

Evaluation

Field Studies

Geomechanical
Model

Containment(Seal Distribution &Effectiveness,Fault Reactivation)

PetrophysicalAnalysis

Seal Potential Model

Output &Outcomes

Analogue Studies
Rock Typing
Core Analysis& Sampling
Well Log
Interpretation &Correlation
SeismicInterpretation
Time-DepthAnalysis
DST, RFT &BHT Analysis
HydrogeologicalStudy

PetrophysicalModelFacies & Seqence
Stratigraphic
Maps & Models
DepthStructure
Maps & Models
P/T Gradients

Groundwater,Salinity

Injectivity(Permeability,Thickness &Heterogeneity)
Capacity(Porosity,P & T)
Integrity(Leakage Pathways,Trapping Mechanisms,
Migration Pathways)

Static & Dynamic
ModelsRisk & Uncertainty
Analysis
Site Selection
Engineering ofReservoir

Hydrodynamics

Source: © CGSS Site Characterisation & Selection Desktop Study Process For Geological Storage Sites

18

3/07/2012

Many interdependencies & iterative processes“no single or simple answer”
But with diligence can map the range of options

Most geologists don’t think linearly“annoys engineers immensely ”

What happens if data is inadequate or uncertain ?
Data poor
Data OKMajor
uncertainty
carried into
project
assessment1019

3/07/2012

Poor project definition will lead to loss of valuei.e.

Changing criteria mid-project – bad practice
Understand technical reality & impact of what is required 13

Depositional environments andmodels

20

3/07/2012

Are some geological solutions / sites going to be a
lot better, more manageable & predictable, thanothers-and how reliable will our risk assessments be –DEPOSITIONALMODELS will greatly
influence thepredicted reservoir
and seal
distribution:
But also consider the scale / area
required for storage… and thus theeffectiveness ofconnectivity andcontainment …
and the amount ofdata and proof
required21

3/07/2012

Stacking patterns
Critical issues in
exploration strategy
and pressure
management will
include;Sediment supply
ProvenanceSediment type

From Lang et al 2001, and Musakti 1997.

“Accommodation” is therelative amount ofsubsidence/uplift and sea
level change in asedimentary basin that
results in the infilling of it bysediments or erosion bydowncutting.
The interplay of sediment source(sand/mud), sea level change(up/down), subsidence rate
(high/low), will all influence thethickness, distribution and typeof sediment in a basin.
Cyclical deposition are commonlyobserved in geology

22

3/07/2012

How interconnected and variable are reservoirs ?

Do they change laterally ?

Lateral variation in rock types (lithologies)
River silt and sand

Lagoon silt and mudRiver mouth sand

Beach sandMarine mud and sand23

3/07/2012

ProgradingSEAROCK

TIME

LAND

TransgressiveSEATIMELANDROCK

Big difference in well numbers to exploit this reservoir

24

3/07/2012

Injectivity ?

Core versus formation permeabilities
Corrected core permeabilities (air vs brine etc)
often do not match formation permeabilities
Due to heterogeneity and barriers and overburdenpressures

Zerogen core corrected permeabilities Kh~100mDm – Catherine Sandstone
Zerogen formation permeabilities (on well test)
1/10th of corrected core permeabilities (Kh)
Exacerbated by low permeabilities and rock type25

3/07/2012

Message 4
Understand your depositional environment systemsvery well,(get your feet wet and sandy looking at modernsystems)
and,think about the area/volume required and what thatmeans for facies (lithology) heterogeneity,and,get “formation” (not just core) injectivity data to help
predict your well numbers

Depositional Environments
Understanding reservoir and seal
heterogeneity will influence numerous
outcomes
Technical
Commercial...... this is just doing our homework properly –normal business practices– or is it
The scale/volume of CO2 injection dwarfs oil andgas production operations26

3/07/2012

HOW BIG A FOOTPRINT IS REALLYREQUIRED FOR LARGE STORAGE
VOLUMES ?

22CO
CO22 algicalologicoloeGe rag
GerageStoStolutionsonsSoSoluti

27

3/07/2012

Lateral variation in rock types (lithologies)
River silt and sandArea is ~ 5 km 2
Lagoon silt and mudRiver mouth sand

Beach sandMarine mud and sand“Pilot Scale” ?
100,000 t/yr
Compared to 5 to 10 Mt CO2 /year (power station)is small …… but
100,000 t CO2/yr= 5.2 mmscf/d (6.49mmscf/d @ 80% online)

This rate equivalent toEOR “field” injection rates in Texas
i.e. multiple injection wells

Water injection floods
It is industrial injection rates for oil and gas operations(Thus need to apply those standards for safe and secure storage)28

3/07/2012

SACROC EOR/CO2 Field

CO2injection
rate

100,000 t/yr
injection
rate

Message 6• Most geological storage sites will be faced withinjection challenges (including pressuremanagement);• whether at pilot or industrial scales (foremissions)• Detailed sequence stratigraphy will be required29

3/07/2012

Conclusions : Storage Ready in Japan
What does Japan think Storage Ready meansfor current projects?
Is Japan there now?
What does Japan need to do to get there?
By when does it need to be in place?
What threatens or is holding Japan back?

CONTACTDr John Bradshaw
Chief Executive Officer
CO2 Geological Storage Solutions
www.cgss.com.au
John.Bradshaw@cgss.com.au+61 (0)2 62804588
Mob: +61 (0)418 624 804

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