This group brings together the best thinkers on energy and climate. Join us for smart, insightful posts and conversations about where the energy industry is and where it is going.


Oil Sands: The Resources, The Technologies, The Consequences

Mark Caine's picture
London School of Economics

Mark Caine is a Research Fellow at the London School of Economics and Political Science. There, he coordinates energy and climate programmes for the Mackinder Programme for the Study of Long Wave...

  • Member since 2018
  • 17 items added with 7,156 views
  • Feb 12, 2013

Canada’s vast quantities of oil sands have been described variously as the world’s third largest proven crude oil reserve, Canada’s path to energy superpowerdom, ‘game over for the climate’, and ‘the most destructive project on earth’. Unsurprisingly, they have become an object of acrimonious public debate and significant political maneuvering.

But what exactly are Canada’s oil sands, and how does oil sand extraction work? What’s at stake with the extraction and use of Canada’s vast oil sands deposits?

This post, the first in a series of two, will explore the oil sands resource, the technology involved in extracting it, and the consequences of doing so. A subsequent post will tackle larger questions surrounding the economics of oil sands and the political debates raging around their extraction, transport, and use.

The Resource

The terms ‘oil sands’, ‘tar sands’, and ‘bituminous sands’ are used interchangeably. Though ‘bituminous sands’ is the most technically accurate, all three terms describe geological formations in which thick, highly viscous bitumen—a form of petroleum that is semi-solid at room temperature—is suspended in a mixture of sand, clay, water, and other trace materials. In-situ oil sands look like black, sticky sand.

Oil sands before oil extraction

Once extracted, bitumen itself is a thick, black fluid of extremely high viscosity (hence the shorthand ‘tar’). It is typically used to make asphalt or processed into synthetic oil, which can be used interchangeably with conventional crude oil.

According to a World Energy Council report, proven reserves of bitumen total roughly 250 billion barrels globally. Of this 250 billion barrels, approximately 178 billion, or 70%, are located in Canada. Almost all of these 178 billion barrels are located in Alberta, and most of this Albertan bitumen lies in a single gigantic formation, the Athabasca oil sands. 

According to analysis by the Canadian Association of Petroleum Producers (CAPP), an industry group, Canadian oil sands output reached 1.6 million barrels per day in 2011, a figure projected to rise to 2.3 million barrels per day by 2015 and 5.0 million barrels per day by 2030.

Technically speaking, bituminous oil sands are easy to access. They’re situated close to the earth’s surface, obviating the need for deep or complex drilling operations. ImageThey’re also favorably situated both politically and logistically: the largest deposits are located in politically stable Canada, and most are concentrated in a relatively small, easily accessible region in Alberta.  

The combination of large reserves, political stability, and geographic concentration has led companies to take a strong interest in Canadian bituminous oil sands and plow large amounts of investment into their exploitation.

The Technology

Oil can be extracted from bituminous sands through a variety of methods. These methods can be divided loosely into two categories: in-situ techniques in which the bitumen is extracted from the sands on site, and strip mining techniques in which the sands are dug up and transported to off-site bitumen extraction facilities.

Strip mining is the simplest and best-known technique; it’s also the most notorious as a result of the scars it leaves on local landscapes.


Of the in-situ extraction methods, the most common is steam assisted gravity draining (SAGD). This technique involves drilling two horizontal wells into an oil sands deposit, one extending above the deposit and the other below it.  Steam is pumped into the deposit through the former, melting the in-situ bitumen such that it drains into the latter. The heated bitumen in the lower well is then pumped to the surface. The Seattle Times has an excellent visual tool depicting this process as well as basic surface mining. Other in-situ extraction processes include cold flow extraction, cyclic steam stimulation, and solvent extraction, and several experimental methods are currently under development.

Once extracted, the final stage of oil sands exploitation is the ‘upgrading’ of extracted bitumen into synthetic crude oil. This is usually done through catalytic hydrocracking, a process often used to separate jet fuel and diesel from conventional crude oil.  Once upgraded, synthetic crude oil can enter the global crude oil supply chain; typically it is transported to refineries to be turned into finished products such as kerosene, gasoline, and diesel.

The Consequences

The extraction of bitumen from oil sands faces two major environmental constraints: the principal extraction techniques tax local water resources, and both extraction and use of oil from oil sands create significant carbon emissions.

According to analysis by the the Pembina Institute, surface mining of oil sands produces 2-4 barrels of waste water per barrel of oil produced. In-situ techniques, at 1.5 barrels of waste water per barrel of oil generated, are less water intensive but still demanding of significant water resources.

The water-intensity of these extraction processes—and the sheer quantity of waste water generated—could impose constraints on future oil sands extraction. So too could legal actions by downstream users of the Athabasca river, which is already showing signs of contamination from oil sands exploitation. 

While the water-intensity of oil sands extraction is important regionally, most global attention has focused on the atmospheric consequences of oil sands exploitation. There are two main issues: the total amount of carbon embedded within oil sands reserves and the carbon emissions associated with extracting oil from bituminous oil sands.

The first issue is more general: the Canadian oil sands represent a huge stock of fossil fuels, the burning of which is inconsistent with the lowering of global carbon emissions and a transition to a low-carbon economy. According to one estimate, current Canadian oil sands reserves represent 22 billion metric tons of carbon dioxide, and total Canadian oil sands resources represent 240 billion metric tons. Clearly, adding 22 billion or more metric tons of CO2 to the atmosphere will not help limit atmospheric CO2 concentrations.

The second issue is that the process of extracting this oil is itself more carbon intensive than extracting conventional oil. According to an analysis by IHS CERA, the ‘well-to-wheels’ emissions of a barrel of oil derived from oil sands is between 5% and 15% higher than those produced by a barrel of conventional oil. According to the US Department of State’s analysis, the figure is closer to 17%. NRDC, who have analysed CERA’s methodology, argue that CERA’s upper bound is far too low and that a range of 8% – 38% is more likely.


Regardless of the precise well-to-wheels figures, the carbon dioxide implications of oil sands are clear: deriving oil from bituminous oil sands is more carbon dioxide intensive than extracting conventional oil, and fully exploiting global oil sands reserves is likely to lead to significant increases in atmospheric carbon dioxide concentrations.

For these reasons, the exploitation of oil sands has become an enormously contentious political issue. In this post, I’ve outlined the basic information on the resource necessary to understand the political and economic debates surrounding it. My next post will analyse the contours of these debates more closely and assess their implications for future oil sands development.

Image Credits:,,

Mark Caine's picture
Thank Mark for the Post!
Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.
More posts from this member
Spell checking: Press the CTRL or COMMAND key then click on the underlined misspelled word.
Rick Engebretson's picture
Rick Engebretson on Feb 12, 2013

Beautiful intro.

There are few efforts in modern history that match this resource utilization program for complexity and importance. It needs to be done with best of skills and intentions.

IMHO, this project will require on-site nuclear process energy, and biochemical supplements to provide a fuel product we have yet to find a replacement for. Several modern technologies to serve a modern solution.

The last thing we can do is ignore this strategic resource. The second last thing we can do is yield to South Texas claims that transporting it there is a good energy strategy. Yet, that is what most dominates the discussion we suffer; choose between horrible and impossible.

So I'm looking forward to more competent discussions like yours, that help make this work.

Robert Hargraves's picture
Robert Hargraves on Feb 12, 2013

The US debate about the Keystone XL pipeline to the US is really a misguided attempt to discourage oil sands petroleum mining in Canada. It is misguided because tar sands oil will simply be replaced by imported oil, and Canada will export tar sands oil by tankership. What is needed to curtail CO2 emissions is an alternative. Technologies are being developed to use advanced nuclear power to manufacture climate-neutral methanol and dimethyl ether for vehicle fuels. Ammonia, too, is a possible fuel, being tested by one Canadian ventureship. Even nuclear hydrogen-fueled vehicles may become practical.

In the meanwhile, at least one Canadian company is considering the use of the liquid fluoride thorium reactor to generate heat and power to extract the oil instead of burning oil and gas for this.

Mark Caine's picture
Mark Caine on Feb 12, 2013

Thanks for this reply Rick. You're absolutely correct that the scale of this resource places it amongst the world's most significant. It's therefore important that we assess it carefully and make smart decisions about how we engage with it.

I'm curious about your statement that Keystone XL is bad energy strategy. What about it do you think is a bad strategic move? Are you opposed just to the pipeline, or to the exploitation of the oil sands in general?

I'm going to be diving into these issues much more deeply in my next post, but I'm curious to hear your thoughts (and those of others) in the meantime.


Mark Caine's picture
Mark Caine on Feb 12, 2013

Thanks for this comment Robert.

I agree with you that the debate over the Keystone XL pipeline is a proxy debate over oil sands exploitation more broadly, and that this exploitation is likely to happen whether or not the pipeline is built. That said, it does seem to me that the movement against the pipeline has slowed down the exploitation of the oil sands by injecting uncertainty into the economics and logistics of major oil sands projects. This represents a victory -- at least a temporary one -- for those fighting against the pipeline. 

You're also correct to point out that what we ultimately need are new, clean technologies capable of providing the same (or better) energy services offered by oil. We sometimes forget just how extraordinary a substance oil is: it's very hard to beat on energy density, stability, and transportability. This is why many clean energy efforts, e.g. advanced biofuels development, focus on emulating its properties. A clean, cheap, energy dense oil substitute would go a long way towards curtailing our CO2 emissions.

Finally, I wasn't aware of efforts to use nuclear power to extract the bitumen from oil sands. That would certainly impact the resource's EROEI and the well-to-wheels carbon emissions oil sands oil, though it's hard to say by how much. I'll be keeping a close eye on those efforts.


Rick Engebretson's picture
Rick Engebretson on Feb 12, 2013

Thanks Mark. In an earlier lifetime I was a pretty good Biophysical Chemist. Then, about 32 years ago I brought my young family to a rural area on the southern edge of the Canadian Shield geologic region in Northern Minnesota. The head of the Department came up and wondered what the heck I was doing. Physics people wanted to see. But this is a hack hobby farm, nothing else (except marsh marigolds and my wife's bluebirds).

So now everybody talks about biofuels and climate. But I want to emphasize this; the scale of forest resources, and warm climate/high CO2 growth rate dwarfs our senses. And with the decline of forest industries like paper and lumber there is little to manage it. I'm delighted to see global interest in food, water, energy nexus. And there is a "World Forests Summit" in Stockholm in March.

Knowing the different chemistries of fossil trees and living trees, the fuels we now prefer are right in between. We can double the life of this fossil resource, and create carbon and water and biodiverse systems. And nuclear advocates seem to have some good ideas.

I just think the Texas oil boys are there for plunder. I don't think they have a good chemistry that can turn this tar into quality fuel. Even if we did pipeline it about the distance from Chicago to London.

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2013

Mark, thanks for your objective and thorough analysis of this issue, one of the best I've seen.

The issue is contentious not because there isn't valuable energy locked in the sands, or because it won't make climate change worse. It's contentious because it directly pits our fundamental values against each other.

We're at a crucial moment in our history, and one that will depend on good information to make the best decision.

Mark Caine's picture
Mark Caine on Feb 12, 2013

Thanks Bob. My goal in this post was to provide a modest overview of the 'good information' that you highlight as necessary to making the best decision(s) on these resources. But, as you suggest, the information provided can't tell us exactly what to do: it merely clarifies the issues at play in our decisions.

Dan Sarewitz done some excellent writing (PDF) on how disputes about fundamental values often take the form of arguments over science. As Dan highlights, science can never 'tell us' what to do: ultimately, we have to make decisions and resolve disputes through a deliberative democratic process, to the extent that this is possible given the contraints on our imperfect democratic system.

As discussions over Keystone XL and oil sands development move forward, let's hope we can have the right conversations and making smart decisions accordingly.

Rick Engebretson's picture
Rick Engebretson on Feb 12, 2013

Jim, I give you credit by helping insert nuclear into the tar sands discussion.

Personally, I'm happy not knowing too much about anything anymore. I used to think like you, combining several ideas into a single idea. But like Bob Dylan said in an interview about his early lyrical masterpieces, "I can't do that anymore."

Mark Caine's picture
Mark Caine on Feb 12, 2013

I'm always looking for sage advice!

John Miller's picture
John Miller on Feb 12, 2013

Mark, beware that the ‘consequences second issue’ is extremely complex and subject to very questionable analyses and assumptions.  I studied this issue in detail beginning a couple years ago.  My analysis shows that the increased WTW ‘fossil fuels’ energy consumption of average U.S. crudes vs. syncrude is 7%.  The higher reported values appear to be due to a combination using the GREET model data, which over predicts refining current baseline fossil fuels energy consumption by over 60%, and, ‘land use change’ (LUC) impacts.  The excessively high base petroleum fossil fuels consumption data significantly inflates the impacts of estimating syncrude processing as do many of the poorly developed the LUC estimates.  LUC analyses assume the loss of forest carbon sequestering and breakdown of substantial bitumen crude oil after exposure to the air (aerobic decomposition).  The LUC analyses often omit or ignore the fact that open pit mining restoration and reforestation activities that follow mining the oil sands are required to return the affected areas to their natural (fully vegetated) states.

No question, when analyzed in isolation, syncrude has increased carbon emissions compared to lighter conventional crudes.  But the carbon increases are in the 5-10% range, not the 20-40% worst case estimates.  In your next post I hope you explore the alternatives in some detail.  Magically shutting down the Canadian oil sands production tomorrow may not be as beneficial towards world total carbon emissions as many people advocate or believe (i.e. such as the current and projected rates of growth in world coal and oil consumption.  Hint, hint.)

Mark Green's picture
Mark Green on Feb 19, 2013

Good discussion of oil sands and I agree, debate in the U.S. over the Keystone XL pipeline is proxy in nature because the pipeline itself will have virtually zero GHG emissions. Otherwise, it's important to know that oil sands extraction has an important reclamation component that perhaps Mark will cover in future posts. When I visited Suncor's operation in Alberta a couple of years ago, I saw a 550-acre former tailings pond that had been restored to lush vegetation with thousands of tree seedlings taking root and teeming in wildlife. Related to that is new technology that allows water reclamation and the drying of clay tailings in a matter of weeks instead of decades - which significantly speeds up the replanting of grasses, shrubs and trees. This is driven by corporate commitment but also by provincial and federal environmental requirements. Canadians care a great deal about the environment, and they're simply not leaving the land scarred. Meanwhile, a great deal of extraction is done through in-situ drilling and steam-assisted gravity drainage that allows a very small footprint in the boreal forest. I'm told that in the future 75 to 80 percent of oil sands extraction will be done this way.

Mark Caine's picture
Mark Caine on Feb 24, 2013

Thanks for your comment John, and for linking me and other readers to your WTW analysis. The reason I provided a range encompassing both government and industry estimates is that in my view the exact syncrude vs. crude WTW GHG emissions differential remains uncertain. As you correctly highlight, the outcome of any given analysis depends on the assumptions governing the model being used, which can differ widely. It's therefore extremely important to analyse a model carefully before accepting its findings and using them to inform policy making.

With that said, I haven't come across many  criticisms of the assumptions underlying the GREET model, though I also haven't studied in detail the components covering the refining of current fossil fuels. Can you point me to some independent analysis of the faults in GREET that you identify? 

Mark Caine's picture
Mark Caine on Feb 24, 2013

Mark -

Thanks for your comment, which correctly identifies an important consideration surrounding the exploitation of Canadian oil sands. As you mention, Canada has stronger environmental regulations than most countries, which means that extraction sites for oil and other resources tend to be less damanging to the local environment than their counterparts elsewhere in the world.

A similar logic applies to the situation south of the border, where some of the KXL syncrude would be consumed: because of industrial and environmental regulations in the US, consumption of Canadian syncrude in the US would likely be more efficient than consumption in Asia, where much of the oil might otherwise flow.

Knowing that the US and Canada have stronger environmental protections than many producers and consumers of oil complicates the KXL picture. If Canadian syncrude would be sent to China in the absence of KXL, is blocking the pipeline a net climate benefit? If less investment into oil extraction in Canada means more investment in less stable, environmentally and socially conscious countries, is Canadian oil sands extraction ultimately a better proposition?



Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »