Allan Armitage prepared a NI 43-101 report for Skyharbour Uranium in 2015. Below is an excerpt from his summary as an example of the uranium deposits being discovered in the Athabaskan Basin in Saskatchewan, Canada over the the past 15 years, many of which exhibit very high grades of uranium, and carry economic values of REE, gold, zinc, and other elements of interest.
JNR explored the subject property between 2004 and 2011 targeting a low-grade / high-tonnage granitic intrusion hosted U-Th-REE deposit. Exploration undertaken on the Way Lake property has mostly involved airborne and ground geophysics, multi-phase diamond drill campaigns, detailed geochemical sampling of drill core, and ground based prospecting and geochemical sampling. Over 20,000 m of core has been drilled on the property over five winter drill programs from 2007 to 2011. With each subsequent drill program an increasingly detailed understanding of the property geology was developed.
The geologic setting for Fraser Lakes Zone B is within a highly tectonized contact between Archean granitoids and the overlying basal Wollaston Group pelitic metasediments. This tectonized contact, or shear zone, is folded around Archean granitic domes and is thickest within the NE-plunging antiformal nose. There are multiple generations of granitic pegmatites with the mineralized pegmatites usually being syntectonic, and older, and non-mineralized pegmatites being late-tectonic, and younger.
U-Pb age dating of magmatic uraninite has returned ages of 1850-1780 Ma for the mineralized pegmatites. The U-Th-REE mineralized granitic pegmatites that define Zone B occur within an antiformal fold nose that is cut by an east-west dextral ductile-brittle cross-structure and younger NNW trending and NNE trending brittle faults. The mineralized pegmatites have been further sub-divided based on mineralogical studies. These studies defined two main groups of granitic pegmatites/leucogranites based on their uranium- thorium (U-Th) versus thorium-rare earth element oxide (Th-REO) contents and their relative position within the antiformal fold nose. The term Group A intrusives refers to the syn- to late- tectonic pegmatites that intrude the northwest limb of the northeast-plunging antiformal fold. The term Group B intrusives refers to
the syn- to late-tectonic thorium-REE rich pegmatites that intrude the central portion of the northeast plunging antiformal fold nose.
The Fraser Lakes Zone B was discovered during the summer 2008 prospecting and drilling (WYL-08-524, 525 and 526). These three holes did not test the optimum target of the graphitic pelitic gneiss and grantic pegmatite contact due to summer ground conditions. However, all three holes did intersect uraniferous mineralized granitic pegmatite. The best results were from WYL- 08-525 which intersected several uraniferous intervals, with the best zone returning 0.081 wt% U3O8 over 12.0 meters from 77.50 to 89.50 meters depth down the drill hole. The Fraser Lakes Zone B deposit is currently defined by 32 NQ drill holes totaling 5,694.0 meters. Zone B mineralization has a strike length of 1.400 meters, trends roughly 240 and dips approximately 30° to the north. In cross-section, the pegmatite hosted mineralization is tabular in shape. The mineralization ranges from 2 to 20 meters in width over a vertical thickness of approximately 175 meters.
The Fraser Lakes Zone B U-Th-REE mineralization is associated with a series of ca. 1800 Ma subparallel granitic biotite-quartz-feldspar pegmatite dykes entrained within the tectonic decollement between the Paleoproterozoic Wollaston Group pelitic and graphitic pelitic gneisses and the underlying Archean granitoid orthogneisses and foliated granites. The U-Th-REE mineralization occurs dominantly in fractured and altered pegmatite and is accompanied by varying degrees of clay (illite, dickite and kaolinite), chlorite, hematite, fluorite and sausserite alteration. The mineralization is associated with elevated concentrations of copper, nickel, vanadium, bismuth, zinc, cobalt, lead and molybdenum. This style of primary uranium mineralization associated with intrusive rocks such as granitic pegmatites and alaskite is commonly referred to as 'Rossing type' mineralization. Examples of this style of mineralization include the Rossing uranium mine, the Valencia deposit, which is currently under development, and the Rossing South deposit which is under exploration, all of which are in Namibia GeoVector was contracted by JNR to complete an initial resource estimate for the Fraser Lakes Zone B and to prepare a technical report on the resource estimate in compliance with the requirements of NI 43- 101.
The author has estimated a range of Inferred resources at various U3O8 cut-off grades (COG) for the Zone B resource models. However it was assumed based on likely economic parameters that a COG of 0.01 % U3O8 would be appropriate for mineral resource reporting. Using a base case COG of 0.01% U3O8, the author has defined an Inferred resource totaling 6.96 M lbs of U3O8 within 10.4 million tonnes at an average grade of 0.030% U3O8 with significant quantities of rare earth element oxides (REO), specifically La2O3, Ce2O3, Yb2O3, and Y2O3. The inferred resource also includes a significant thorium component.
Using the base case COG of 0.01% U3O8, the Inferred resource includes 5.34 M lbs of ThO2 at an average grade of 0.023%. The resource was determined from a database of 1,283 assay results in 32 drill holes totaling 5,694 metres of drilling completed by JNR between August, 2008 and April, 2011. The drill holes are spaced primarily 75 to 250 meters apart along a strike length of approximately 1,400 meters. The drill holes tested mineralization to a vertical depth up to 175 meters. Mineralization varies in thickness from 2 meters to over 20 meters. The resource estimate is categorized as Inferred as defined by the Canadian Institute of Mining and Metallurgy guidelines for resource reporting. Mineral resources do not demonstrate economic viability, and there is no certainty that this mineral resource will be converted into mineable reserves once economic considerations are applied.
A focused exploration program was recommended by the author for the Way Lake property. The primary objectives are to define additional resources at the Fraser Lakes Zone B by establishing the potential for extension of the mineralized zone to the east and west of the currently defined deposit. Additional priorities are to establish the potential for mineralization in the T-Bone Lake, Fraser Lakes Zone A and Fraser Lakes North target areas identified by geophysics and previous drilling. In addition, further interpretation of geochemical and assay data in conjunction with geological and structural analysis will improve the effectiveness of targeting for future drill programs. Total cost of a recommended work program is estimated at approximately CAD $3.1 million and includes administrative costs at 10%.
[For additional information on the mineralization in and around the Athabasca Basin in Canada see:
http://i2mportal.com/search_resource.php?search_value=The+Athabasca+Basin#page=1 ]
Managed & Built by I2M Consulting, LLC | © 2010-
