Post by
megacopper on Feb 25, 2007 6:01pm
Geological Twins - Athabasca and Sibley
GEOLOGICAL TWINS? THE SIBLEY BASIN COMPARED TO THE URANIUM --RICH ATHABASCA BASIN
Located in northwestern Ontario, the Sibley Basin (sometimes referred to as the Nipigon Basin) shows a number of similarities to the uranium-rich Athabasca Basin in northern Saskatchewan.
The Athabasca Basin is home to the largest high grade uranium deposits in the world.
These similarities have long been recognised and led to a modest amount of exploration for uranium in the area in the late 1970s and early 1980s. From a geological standpoint, similarities between the Athabasca and Sibley/Nipigon basins include:
* Both areas are unmetamorphosed, continental sedimentary basins;
* Both basins were formed during the Helikian age (the Athabasca Formation 1,350 my, Sibley Group 1,339 my);
* Both basins have well developed deep paleo-weathering of basement rocks at the unconformity where the sediments overlie Archean to early Proterozoic basement rocks;
* Both basins overlie basement rocks with high background uranium contents and/or zones of uranium enrichment;
* Both basins have been intruded by Helikian-age mafic magmatic activity (e.g. diabase dykes and sills in the Atha-basca Basin; the Nipigon sills in the Nipigon Basin);
* The basement rocks under both basins contain chemical traps (such as graphitic units) that are capable of reacting with uranium-bearing groundwater to precipitate and concentrate uranium mineralization.
The southern part of the Nipigon Basin, between Lake Nipigon and Lake Superior, is the most favourable for uranium exploration. In this area, Sibley Group sediments overlie "uraniumrich" metasediments and granitic intrusives of the Quetico subprovince. At the northern margin of the Quetico rocks, the basement rocks change to metavolcanics and metasediments of the Wabigoon subprovince, containing abundant graphitic units, sulphide zones and iron forma-tions, all of which represent potential chemical traps for uranium.
The southern part of the Nipigon Basin is very accessible, with an extensive network of logging roads, which allow overland access to most areas for exploration purposes. Recent government airborne radiometric and magnetic surveys and high-density lake sediment surveys have provided an excellent database to guide project selection and regional exploration.
Athabasca Basin Compared to the Sibley Basin
The Nipigon Basin, sometimes referred to as the Sibley Basin, is a Mesoproterozoic (Helikian: 1.6 to 0.9 Ga) conti-nental sedimentary basin that shows a number of similarities to the uranium-rich Athabasca Basin in northern Sas-katchewan. These similarities have long been recognised and led to a modest amount of exploration for uranium in the Nipigon area in the late 1970's and early 1980's. Overall, the Sibley Group sediments in the Nipigon Basin consti-tute the least explored of all the Helikian-age sedimentary formations in Canada.
Similarities between the Athabasca and Nipigon basins are:
Both are unmetamorphosed, continental sedimentary basins.
Both basins are of Helikian age (Athabasca Formation 1,350 my, Sibley Group 1,339 my).
Both basins have well developed regolith (deep paleo-weathering) of basement rocks at the unconformity where the sediments overlie Archean to early Proterozoic basement rocks.
Both basins overlie basement rocks with high background uranium contents and/or zones of uranium enrichment.
Both basins have been intruded by Helikian-age mafic magmatic activity (e.g. diabase dykes and sills in the Atha-basca Basin; the Nipigon sills in the Nipigon Basin).
The basement rocks under both basins contain chemical traps (such as graphitic units) that are capable of reacting with uranium-bearing groundwater to precipitate and concentrate uranium mineralization.
The southern part of the Nipigon Basin, between Lake Nipigon and Lake Superior, is the most favourable for uranium exploration. In this area, Sibley Group sediments overlie "uranium-rich" metasediments and granitic intrusives of the Quetico subprovince. At the northern margin of the Quetico rocks, the basement rocks change to metavolcanics and metasediments of the Wabigoon subprovince, containing abundant graphitic units, sulphide zones and iron forma-tions, all of which represent potential chemical traps for uranium.
The southern part of the Nipigon Basin is very accessible, with an extensive network of logging roads, which allow overland access to most areas for exploration purposes. Recent government airborne radiometric and magnetic sur-veys and high-density lake sediment surveys have provided an excellent database to guide project selection and re-gional exploration.
Comment by
QTraderOne on Feb 26, 2007 7:57am
Informative post! Thanks.
Looking forward to what comes out of the Sibley Basin. If Otish and Labrador are any indications of a uranium presence in Eastern Canada then we have some interesting days ahead for sure.
Exciting times to be in the miners.
Cheers,
QT