Exploration and Development Of - ESAA · 2016-04-14 · Exploration and Development Of A New...
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Exploration and Development Of A New Disposal Zone for Steam Assisted Gravity Drainage Mike Brewster, P.Geol., Devon Canada Corporation Sheldon Thistle, M.A.Sc., P .Geol, Devon Canada Corporation Jon Fennell, PhD., P.Geol. Integrated Sustainability Consultants Gordon MacMillan, P.Geol., Matrix Solutions Inc.
Transcript of Exploration and Development Of - ESAA · 2016-04-14 · Exploration and Development Of A New...
Exploration and Development OfA New Disposal Zone for Steam Assisted Gravity Drainage
Mike Brewster, P.Geol., Devon Canada CorporationSheldon Thistle, M.A.Sc., P .Geol, Devon Canada CorporationJon Fennell, PhD., P.Geol. Integrated Sustainability ConsultantsGordon MacMillan, P.Geol., Matrix Solutions Inc.
Motivation
The SAGD Water Cycle
Water source and disposal are integral to the SAGD process
Disposal Volumes by Zone
4
98% of disposal is into the basal McMurray Aquifer
Bitumen over Basal AquiferWhy disposal into McMurrray can be a problem
5
Wabiskaw Marker
McMurray Formation
Bitumen Resource
Basal Aquifer
Pre_K Unconformity
“NOT IDEAL”Pchamber < Pbw
Water influx
Bottom water pressure (Pbw)
Steam chamber
Pinj
Pprod
Basal McMurray AquiferCurrent Water Disposal Zone
Jackfish 1 SAGD Pads
Disposal Wells
Increasing Disposal = Increasing Pressure
J1 Steam
J2 Steam
J3 Steam
Pre
ssu
re (
kPa)
Tota
l Mo
nth
ly W
ater
D
isp
osa
l (m
3)
Pressure Management Options
Lowering aquifer pressure can be achieved by:
Reducing wastewater disposal
Reducing leakoff from SAGD pads
Source water production - 2 McMurray source wells in 2014
Alternative Disposal :
X Remote disposal in East McMurray
X Devonian carbonates
Other options ?
The Opportunity
Grand Rapids C Aquifer High Salinities – Problem or Opportunity
Exploring for Source Water
34,000 mg/L
54,000 mg/L
Jackfish
Pike
Petrophysical Salinity Calculation102/08-21-074-05W4
Calculated Salinity 15,000 to 45,000 mg/L TDS
(Subsequent water sample TDS = 36,600 mg/L)
Petrophysical Salinity MappingTDS > 4,000 mg/L
Calculated TDS 4,000 – 60,000
(mg/L)
High Salinity ZoneTDS 20,000 to 54,000 + mg/L
Non-Saline WaterTDS < 4,000 mg/L
Non-Saline Water
The Challenges
Challenges and Questions
• Geologic
– Appropriate geologic setting
– Vertical containment
• Hydrogeology
– Groundwater flow, lateral containment
– Injection capacity
• Geochemical
– Source of salinity
– Degree of freshwater interaction
• Regulatory
– Above base of groundwater protection (BGWP)
– No precedent for SAGD disposal
Can the Grand Rapids C be safely used as a disposal zone?
Grand Rapids PaleogeographyDepositional History
“…Thick barrier island complexes with a brackish-water embayment behind that extended as far south as northern Montana.”- Smith et al (1994)
“In Albian time, a terrigenous influx of Cordilleran origin prograded upper Mannville coastal and continental deposits more than 480 km from southern to northern Alberta. A multitude of shoreline sand trends which span Alberta in an east-west direction were deposited.”- Jackson(1983)
Prograding Shoreface LobesGrand Rapids A, B and C
Grand Rapids C
Grand Rapids B
Grand Rapids A
Grand Rapids C 1AA/10-04-074-05W4 - Core
Local Mapping of Grand Rapids CNet Wet Porous Sand Isopach
Christina Channel
Wiau Channel
Sunday Creek Channel
A
A’
Regional Cross-Section
19
B Shale
C Aquifer
Clearwater
Sunday Creek Channel
WiauChannel
Sunday Creek Channel
Sunday Creek Channel
Prospective Disposal Area
Bedrock
GR Top
200
250
300
350
400
450
500
550
600
650
700
0 250 500 750 1000 1250 1500 1750 2000 2250
Elev
atio
n (
m a
sl)
Pressure (kPa)
Quaternary
Grand Rapids C
Elevation vs Pressure
Grand Rapids C is significantly under-pressured
Hydrostatic Gradient Slope
HydrodynamicsCalibrated Steady State Model
Zone of Relative Stagnation
Geochemistry and Isotopes
• Water in Grand Rapids C is Na-Cl type
• high TDS samples > 25,000 yrs BP
• Quaternary 7,000 – 13,000 yrs BP
• 2H and 18O, Cl/Br ratios suggest older formation water mixed with glaciogenic meltwater recharge
Findings Summary
Christina Channel
Wiau Channel
Sunday Creek Channel
Interaction of Source and DisposalParticle Tracking Over 90 years
No interference predicted
Saline Water Interface
Summary
• Anomalous high salinity zone in the Grand Rapids C identified as a potential disposal opportunity
• Hydrodynamic and geochemical evidence suggests a zone of relative stagnation
• Source of salinity appears to be primarily old formation water
• Freshening appears to be mixing with glacially injected meltwater recharge
• Modelling results indicate zone can be safely used for water disposal
• Conditional disposal approval (D51/65) obtained from AER in December 2015
Thank you.
D51 Injectivity Test Results
Safe Injection Rate: ~ 4,800 m3/day @ Max WHIP
