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Proactive disclosure Print version   | |  Co-operative Geological Mapping Strategies Across Canada : COGMAPS EXTECH IV Athabasca Uranium Multidisciplinary Study, Saskatchewan and Alberta
Uncomformity-Sssociated Uranium Deposits Athabasca Basin A major contribution of the Athabasca Uranium Multidisciplinary Study was to share and synthesize knowledge, originally acquired separately in each province and hidden in office drawers, and to add new knowledge through this new partnership across a transparent border. This "EXTECH IV" Project thus removed provincial boundary "faults" and enhanced both sustainable economic development and employment of northern people in the nuclear energy industry.
Rational We aim to enhance the geoscience knowledge framework and EXploration TECHnology to help find the world's best uranium deposits under the Athabasca Basin (the Basin) in northern Saskatchewan and Alberta, and ultimately apply this knowledge to other Canadian targets. These tools will help industry sustain development and production of 40% of the world's nuclear energy fuel, and thereby maintain employment of First Nations people in the region. Approach In 1999-2000, expert workshops by stakeholders assessed knowledge gaps and proposed multi-partnered, multi-faceted research. Within three-years, fifteen sub-projects and 80 scientists had gathered, interpreted and integrated data. Individual write-ups consumed a full year. The results are now being compiled and synthesized in a final volume. EXTECH IV is now part of the Athabasca Synthesis Subproject, Western Churchill Metallogeny Project, Northern Resources Development Program of Earth Sciences Sector, with similar and added partners. Geology and Results
Our targets are hidden beneath a vast plain of elongated hills, carpeted with Jack Pines and punctuated by thousands of lakes rimmed by black spruce. Beneath this Taiga landscape, up to 1.5 km of the non-descript pebbly sandstone Basin dip gently inward, blanketing relatively tiny pods of nearly pure uraninite (U3O8) that are encased within natural clay barriers. The Basin and its hidden deposits have rested unconformably for more than 1.5 billion years on previously weathered 2-3 billion year old banded gneisses of the Canadian Shield. Similar basins in Arctic Canada and once-connected northern Australia also conceal such uranium deposits. After northwesterly flowing braided rivers filled the Basin, it was worn down and re-covered many times. About 12,000 years ago a 2.5 km-thick ice sheet bulldozed these strata into elongate oval hills called drumlins, and scraped off the edges to expose small showings. These attracted little fanfare until the Rabbit Lake deposit was discovered at the eastern rim in 1968 and started producing 20% of the world's nuclear energy fuel. Airborne gamma ray spectrometry and prospecting helped discover other shallow deposits. New ideas, such as conductive graphitic zones in the gneisses, helped discover the deep but super-rich Cigar Lake and McArthur River deposits in the 1980's. Now, EXTECH IV regional studies have resolved "boundary faults" between Saskatchewan and Alberta, defined new basement and basin units, ages and geometries of regional and subsidiary ore-related faults, and thus enhanced the knowledge framework for exploration. We learned that old faults created small valleys that were filled by Basin sandstones, and were reactivated as part of ore formation.
Ancient (1.4 b.y.) oil residues are now distinguished from younger bitumen throughout the Basin and shown to post-date ore. New standards were developed for uraninite dating, and detrital zircon geochronology is finally constraining the timing of deposition (e.g. 1.66 billion years for Sequence 3) and alteration related to ore formation (starting at 1.5 billion years ago). Borehole geophysics has served as a Rosetta stone to link the many results.
Outcomes Although impacts usually are realized over decades, new companies have staked most of the Alberta portion of the Basin and existing companies are consolidating their holdings in Saskatchewan, Alberta and elsewhere. Workers are applying new ideas and EXploration TECHnology with confidence to exploration and land-management by industry and governments. EXTECH IV has trained 10 young scientists, and preserved much old and new information in public archives. Participants Cameco, COGEMA, the geological surveys of Saskatchewan and Alberta, the Geological Survey of Canada, the universities of Saskatchewan, Regina, Alberta and Laurentian and several smaller companies and individuals such as GEOSYSTEM Canada, Inc. and Paul Ramaekers have together contributed more than $8 million in kind and cash and more than 80 scientists and managers. The Final Volume is being sponsored by the Mineral Deposits Division of the Geological Association of Canada, the Saskatchewan Geological Society and the Geological Survey of Canada. More Information Please contact Dr. Charlie Jefferson or Gary Delaney (306-787-1160). Participants and products are listed on the EXTECH IV: Athabasca Uranium Multidisciplinary Study Web site.
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