Regional and Historical Information

Regional Geology and Uranium Potential

The Thelon Basin is a Paleoproterozoic intracratonic basin that is coeval with the Paleoproterozoic Athabasca Basin, Saskatchewan. The Thelon Basin and particularly the southwestern Thelon Basin was filled by Paleoproterozoic unmetamorphosed arenceous sedimentary rocks (the "Thelon sandstone or Thelon Formation"), which have sustained high-grade diagenesis and vary in dip from flat lying to moderately tilted. These siliciclastic rocks which are dominated by fine- to coarse-grained sandstones with coarser equivalents, granulestone to conglomerate, unconformably overlie an ortho- and paragneiss-bearing older basement complex inferred to be comprised of rocks belonging to the Archean and Early Proterozoic. The high-grade paragneisses were derived from pelitic to psammitic protoliths, some of which are graphite-bearing. Numerous northeast-trending crustal-scale high strain zones which subdivide the basement gneiss complex into panels continue to the northeast beneath the Thelon Basin. The rich structural metamorphic history in these metasedimentary belts includes an episode of post-Thelon brittle reactivation.

The Boomerang Property straddles the western margin of the southwest (SW) Thelon Basin and extends eastward covering Paleoproterozoic basement domains described above and where the Thelon sandstone - basement contact is considered to be highly prospective for high-grade unconformity-related uranium deposits. The primary area of interest on the Boomerang Property is a NE trending belt of supracrustal rocks, sometimes referred to as the Elk River Belt of Archean or Proterozoic Age. This belt or corridor of supracrustal rocks consists of a suite of psammitic to pelitic metasedimentary rocks with accompanying intermediate to felsic volcanic rocks. This older sequence of meta-volcano-meta-sedimentary sequence is overlain unconformably by the flat-lying un-metamorphosed Paleoproterozoic Thelon Formation consisting of basal fluvial non-marine conglomerates and quartose sandstones.

SW Thelon Basin Historical Exploration

The exploration history in the southwestern Thelon Basin was episodic. The initial exploration was conducted by Urangesellschaft Canada Ltd. (UG), Pacific Nuclear Corp. (PNC), Gulf Minerals and Hudson Bay Oil and Gas. These companies left behind a rich data legacy in the form of regional and detailed geological mapping, soil, lake sediment and water geochemical surveys and airborne and ground geophysical surveys which have been captured and utilized for Uravan's ongoing exploration.

Previous exploration on lands now covered by the Boomerang Property was conducted by Urangesellschaft Canada Ltd ("UG") between 1976 and 1984 and PNC (Canada) Exploration Co. Ltd. ("PNC") in 1990 and 1992. At the time these exploration companies focused on a narrow corridor of graphitic conductors within pelitic gneisses that are overlain unconformably by 80 to 100 meters of Thelon sandstone. Both UG and PNC drill tested these conductors in 1983 and 1991-1992 respectively, with 51 vertical BQ-size diamond drill holes totaling 6,536.7 meters. Significant results were obtained from drill hole BL-83-21, which intersected 0.5 meter grading 0.50% U3O8, 22.4 g/t Au, and 12.3 g/t Ag in strongly altered Thelon sandstone at the faulted unconformity contact. Drilling along the conductive corridor also intersected anomalous uranium and precious metal mineralization, a feature that conclusively demonstrated the high potential of this graphitic metasedimentary belt which had been comparable to the Wollaston Group graphitic metasedimentary rocks beneath the Athabasca Basin.

Other historic exploration work conducted on the Boomerang Property area was performed by UG, PNC, Gulf Mineral and Hudson Bay Oil & Gas between 1976 -1984 and 1990 - 1992 consisting of regional geological mapping, surficial geology mapping, lake sediment and soil sampling/geochemistry and airborne and ground geophysical surveys.

In June 1998, Uravan assumed control of the five Boomerang mineral leases and completed 10 vertical NQ-diamond drill holes totaling 1322.4 meters. This drill program was designed to confirm the continuity and orientation of the discovery mineralization in BL-83-21 and to test this mineralized conductor and surrounding conductors for larger mineralized zones. Drill hole BL-98-52 intersected mineralization immediately beneath the unconformity: 1.0 meter (83.5-84.5 meters) grading 595 ppm U, 10.17 g/t Au, 5.7 g/t Ag, 358 ppb Pt and 497 ppb Pd. Within the former interval, there is a subunit, 84.0-85.0 meters grading +1.0% As, 0.36% Ni, 0.61% Co and 419.5 ppm Cu. These intersections conclusively demonstrated that the unconformity-related mineralizing processes were operative along the conductive corridor and that more drilling was warranted. The structural and alteration style associated with the Boomerang discovery mineralization and the metallic expression of that mineralization, U+Au+Ag+Ni+Cu+Co+As, is comparable to the Cigar Lake deposit, eastern Athabasca Basin.

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Uravan believes this initial reconnaissance drill program was a significant technical and geological success particularly in defining a second zone of unconformity-related sulphide mineralization-alteration in the F-trend and similar mineralization-alteration in the newly recognized G-trend. These results confirm the resolve for enhanced multi-disciplinary exploration programs focused on tracing the highly encouraging 2006 results towards discovery of unconformity-related uranium deposits within both these highly prospective conductive trends. 

In July 2006 Fugro completed a new airborne MEGATEM + magnetic geophysical survey, extending the 2005 survey to the northeast (BN claim group) covering the projection of the G and F conductors.  In this new survey a total of 2992 line-kilometers of geophysical data were collected by flying 400 m spaced traverse lines.

Based on interpretive work from the merged 2005 and 2006 MEGATEM geophysical data, the new 2006 MEGATEM survey confirmed the substantial extension to the northeast of both the G- and F- conductive trends thereby adding the G-extension and H1 to 8 series of EM anomalies respectively (Figure 2).