Crosshair Exploration Corp.

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Madsen Lake Croteau Lake
Project Highlights
  • intense uranium anomalies associated with the many crosscutting structures

  • Michelin-style mineralization

  • Geophysical surveys and intensive ground exploration programs have identified numerous targets



Geology


Geology Map with Target Areas
The Central Mineral Belt project lies on an area composed of Archean to Mesoproterozoic gneissic, sedimentary, volcanic and granitoid rocks. The project lies near the junction of three regional faults, where the Grenville front overprints the northeast trending boundary between the Nain and Makkovik tectonic Provinces. Basement to the area is Archean gneiss of the Nain craton.

The local geology comprises Early Paleoproterozoic submarine volcanic and sedimentary rocks of the Moran Lake Group overlain unconformably by the late Paleoproterozoic continental sediments and subaerial volcanics of the Bruce River Group. The Moran Lake stratigraphy was deformed during the Makkovikian Orogeny, and after a hiatus of perhaps 500 Ma without sedimentary record, the Bruce River Group was deposited above a profound angular unconformity.

The Moran Lake Group consists of shale, arkose, and dolostone overlain by iron formation in the southwest and pillowed basalts to the northeast. The Bruce River Group consists of a basal, polymictic conglomerate and sandstone overlain by tuffaceous sandstone.

The geology at the southern portion of the property consists mostly of continental sediments and volcanics of the Bruce River Group. The Bruce River Group is comprised of basal, polymictic conglomerates and sandstones of the Heggart Lake and Brown Lake Formations overlain by felsic volcanic tuffaceous sandstones of the Sylvia Lake Formation. The Sylvia Lake Formation is the thickest and most aerially extensive unit of the Bruce River Group. The geological setting and mineralization style are similar to that of the Michelin deposit located 65 kilometres to the northeast.

The main targets of the Lonestar Division include the Croteau Lake and Madsen Lake areas.

Mineralization in the Croteau Lake area is hosted by variably deformed iron formation at the unconformable contact between shale and slate of the Warren Creek Formation and conglomerates and sandstone of the Brown Lake Formation. Mineralized samples are enriched in U (up to 2.087% U3O8), V (up to 0.803% V2O5), Ag (up to 9.2 g/t Ag), Cu (up to 0.51% Cu), and limited Au (up to 422 ppb Au).

The Madsen Lake area is underlain by felsic volcanics and sandstones of the Sylvia Lake Formation. Crosscutting diabase dikes are typically sheared along the contact with the felsic volcanic. Shear zones are usually less than 2 m wide, but are found over an area approximately 100m wide with a strike length of 1.8km. Mineralized fractures parallel to and crosscutting the sheared zones are mineralized. The felsic volcanics typically have high background radiometric values, ranging from 150-250 cps, and rarely as high as 350 cps. The localization of uranium mineralization at Madsen Lake is structurally controlled.

Exploration Work

The extent of uranium mineralization within the southern portion of the Property was confirmed in late 2005 following a 7,062 line kilometer airborne radiometric and magnetic survey. The survey revealed the most intense uranium anomalies both in size and magnitude identified on the property to date.

Detailed ground exploration programs on the southern portion of the Property were carried out in both 2006 and 2007 and included prospecting, geological mapping, sampling, alpha-track, till, and lake sediment geochemical surveys.

Although drilling at the CMB has largely been concentrated on targets under the direction of the Northstar Division, very limited drilling programs have been completed in the southern portion of the Property. A total of 1,946 m was drilled on the southern portion of the Property in 2006, 2007 and 2008 and included drilling at both Madsen Lake and Croteau Lake.


For additional information on exploration work, please see Croteau Lake and Madsen Lake