A Comparison of Unconventional Reservoirs in Canada
Robert Mitchell, Canada Sales Manager
Geosciences & Petroleum Engineering (GPE)
PetroTechnical Services (PTS)
What Does Unconventional Mean?
• Wikipedia—Petroleum extracted using techniques other
than conventional
• IEA—In general conventional is easier and cheaper to
produce than unconventional. Categories of unconventional
and conventional change over time as economic and
technical conditions evolve—unconventional can migrate to
conventional.
• AER—Unconventional refers to low permeability rock where
the pores are poorly connected, making it difficult for oil and
natural gas to move through the rock to the well.
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Unconventional…
Unconventional fluid
• Heavy oil
• Bitumen
Unconventional reservoir
• Tight Oil/Gas
• Shale Oil/Gas
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Unconventional Oil and Gas in Canada
Heavy oil
Bitumen
Tight/Shale gas
Tight/Shale oil
“EOR”
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Shale Gas
Liard
Shale Gas
Horn River Basin
Heavy Oil and EOR
Bitumen
Tight Gas
Montney
Shale Gas
Duvernay
Heavy Oil
Tight Oil - Bakken
and EOR
Bitumen
Very high density (very high viscosity)
Production mechanism:
• Mining
• Steam Assisted Gravity Drainage (SAGD)
• Cyclic Steam Stimulation (CSS)
• Chemical Injection
Challenges: Environmental footprint. Cap Rock Integrity. Cost
of Steam. Shale.
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Heavy Oil
High density (high viscosity)
Low primary oil recovery (~5-10%)
Low cost, high volume
Production mechanism:
• Cold production
• Cold Heavy Oil Production with Sand (CHOPS)
• Post CHOPS thermal
Challenges: Under characterized. Water production. Hit or miss
for production. How to get 20% (or higher) recovery?
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Enhanced Oil Recovery
Mature oil fields
Primary recovery has finished
Water, chemicals, CO2, Water Alternating Gas (WAG)
Challenges: Which method to use? How to optimize field
development? Often under characterized.
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Tight & Shale Oil/Gas
Low porosity (3-6%)
Low permeability (under 0.01mD)
Gas is easier than oil to flow
Production mechanism:
• Hydraulic fracturing
• Horizontal, multi-well pads
Challenges: Heterogeneities. Costs. Understanding of how the
fractures go for field development.
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Challenges with $50 Oil…
Maximize capital investment
• Drill less wells, produce more
• Re-Fracturing existing wells
• Migrate to EOR
• Optimize completion strategy
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Unconventional Reservoirs
cFRAC’s
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Effective Fracturing ??
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Engineering Completions to Increase Productivity
CQ
Engineering process for completion design
 Reservoir properties—Reservoir Quality (RQ), Completion Quality (CQ)
 Structural constraints—Natural fractures, faults, etc.
 Operational constraints—Injections rate, stage length, etc.
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+
RQ =
Composite
Engineered Completion—Montney Example
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Unconventional Oil and Gas
Definition of Unconventional
Understanding and Challenges for Unconventional Reservoirs
• Heavy Oil & Bitumen
• Tight and Shale Oil/Gas
Engineered Completion
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Reference Technical Papers
SPE 163855—Asset Development Drivers in the Bakken and
Three Forks
Bilu V. Cherian, SPE, Schlumberger; Chris M. Nichols, SPE, Continental Resources Inc.;
Maraden L. Panjaitan, SPE, Schlumberger; Jayanth K. Krishnamurthy, SPE; Jason
Sitchler, SPE, Schlumberger
SPE 171662-MS—Back to the Future: Shale 2.0 - Returning
Back to Engineering and Modelling Hydraulic Fractures in
Unconventionals With New Seismic to Stimulation Workflows
V. Ramanathan, D. Boskovic, A. Zhmodik, Q. Li, M. Ansarizadeh, Schlumberger Canada
Limited
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