As North America tries to obtain energy security it will have to rely on more unconventional resources to fulfill its energy needs over the next decades – and balanced with that is the need for stewardship of the environment and the need to develop more sustainable strategies.
One of the largest unconventional resources in North America is the oil sands of northeastern Alberta.
Most of the world’s oil sands are found in Venezuela and Canada – and in Canada, the oil sands occur in Cretaceous fluvial-estuarine deposits of northeastern Alberta, covering an area of more than140,000 square kilometers.
Bitumen also is hosted in carbonates in Alberta, but to date these have not been commercially produced. In 2008, Alberta’s reserves estimates of remaining established bitumen reserves is 170.4 billion barrels (Gb), making it one of the world’s largest hydrocarbon accumulations.
In North America all of the bitumen currently being produced is from Alberta. In 2008 Alberta’s crude bitumen production totaled 477 million barrels (75.9 million cubic-meters). This total production is equivalent to 1.31 million barrels per day (207.4 thousand cubic-meters per day).
To put these numbers in perspective, in total only about 3.6 percent of the initial established crude bitumen reserves have been produced since 1967 when commercial production began in the province.
Only about 22 percent of the established oil sands reserves in Alberta can be recovered through surface mining, with the remaining 78 percent recoverable using in-situ, mainly thermal technologies. The most common in-situ technologies are cyclic steam stimulation and steam assisted gravity drainage (SAGD).
Recent research interests related to SAGD-development strategies include:
- Mapping thin overburden, karst and glacial deposits.
- Prediction of steam migration with permanently installed fiber-optic monitoring.
- Experimental in-situ thermal coil heating of bitumen.
- Use of developing technologies to reduce greenhouse gas emissions and tailings disposal.
- Remediation of the landscape to return the sites to a biodiversity at least equal to the prior biodiversity index.
- Transportation alternatives using new and existing infrastructure of pipelines and railways.
Earlier this year the Canada’s Energy Resources Conservation Board issued a directive that outlines new cleanup rules and penalties for non-compliance regarding tailings ponds regulations for the oil sands areas.
Future critical technology needs mainly concern the development of more environmentally friendly methods of extraction, production and upgrading of oil sands.
Most of the future bitumen resources will be extracted by in situ technologies. Because there is significant production of greenhouse gases with bitumen production and upgrading, critical technology needs involve research into:
- Alternative sources of heat for generation of steam (i.e. geothermal, nuclear, burning of slag).
- Use of other methods to reduce the viscosity of the bitumen so it will flow to the well bore or through pipelines more easily (i.e. diluents, catalysts, microbial and nanotechnology).
- Underground in-situ extraction, refining and upgrading.
- Co-sequestration of greenhouse gases by injection into abandoned reservoirs or other geologic media.
Beginning in the mid-1970s, the North American energy crises have made the Canadian oil sands a more strategic unconventional energy resource for North American interests.
With increased energy demand switching to unconventional, other areas most likely for future oil sands growth include the northwestern portion of Saskatchewan in the Western Canada Sedimentary Basin; the Colorado Plateau, Uinta and Paradox basins of Utah; the North Slope of Alaska; the Black Warrior Basin, Alabama; the Maverick Basin, southwest Texas; the Borderland Basins of California; the Eastern Interior and Appalachian basins of Kentucky and Illinois; and the Tri-State, Mid-Continent region of Kansas, Missouri and Oklahoma.
As with development of these vast resources in Canada, oil sands development in the United States will have to address the critical environmental issues as related to the balance between greenhouse gas emissions and water/energy usage and the recovery, production and upgrading of bitumen.