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Geology of the Detour Lake Deposit. Deposit geology Gold mineralization. 1. Detour Lake – Deposit geology. 400m. US$775 reserve pit. Sunday Lake Deformation Zone. Gold mineralization occurs in a vein field extending > 3 km along strike, width of 200-350 m and 1 km below surface. 2.
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Geology of the Detour Lake Deposit Deposit geology Gold mineralization 1
Detour Lake – Deposit geology 400m US$775 reserve pit Sunday Lake Deformation Zone • Gold mineralization occurs in a vein field extending > 3 km along strike, width of 200-350 m and 1 km below surface 2
Mafic massive flow Chert Marker Horizon (CMH) Footwall volcanic and sedimentary rocks Mafic pillow flow Ultramafic rocks and chloritic greenstone Main mineralized zones Lithology and Mineralization $775 reserve pit CMH SLDZ 3
Sunday Lake Deformation Zone DG-07-248 150m (massive mafic flow) Upper Detour Lake Fm 0.4 g/t Alteration Strain SLDZ • SLDZ is a 10-50 m wide sub-vertical high strain corridor • Several sub-parallel, E-W striking high strain zones associated with gold minerali-zation occur in HW of SLDZ (talc-chlorite schist) Lower Detour Lake Fm 3.6 g/t 0.2 g/t 8.2 g/t 161m 4
Hanging Wall Mafic Volcanics DG-07-128 2.0 g/t 177.6m 0.3 g/t Mafic pillow flow 180.9m 6.3 g/t 183.6m 1.5 g/t 188.3m Alteration Strain 0.1 g/t 189.9m 0.01 g/t 191.2m Stretched vesicles in barren flattened pillow 194.3m 0.03 g/t Mafic massive flow 0.05 g/t 197.1m 3.0 g/t Au 0.02 g/t 202.0m Pyrrhotite and pyrite emplaced along pillow margin and breccia 0.04 g/t 207.3m 5
CMH and SLDZ Mineralization DG-09-658 152.4m 152.7m 1.5 g/t 154.8m 0.3 g/t Alteration Strain 0.5 g/t 165.3m 1.2 g/t 18.6 g/t 170.0m 0.7 g/t 175.2m 3.6 g/t CMH, a highly silicified and mylonitized rock, incorporated within SLDZ throughout the deposit 0.6 g/t 180.4m Po and Py veinlets in ultramafic rocks in SLDZ 6
31.2 g/t Au 1 cm Gold Mineralization • E-W striking stockwork of qtz-carb veins developed along sub-parallel high strain zones in HW of SLDZ • Strong biotite alteration SLDZ 7
Vein Geometry – 280°/90° • Qtz-carb veins generally strike E-W with steep dips, up to several cm’s thick, contain visible gold and are variably deformed • Qtz-carb stockwork overprinted by auriferous Py-Po-Cpy veins and aggregates, preferentially deposited in low-stress structural sites Average vein orientation 280/90 91.5 g/t Au 2.2 g/t Au 8
Shear Zone Kinematics E W Boudinaged qtz vein sub-parallel to steep dipping E-W striking foliation S N Steep mineral stretching lineation Flat extensional qtz vein Flat pyrite-pyrrhotite vein • Structures observed indicate reverse north-over-south kinematics at Detour Lake Asymmetric pressure shadow around plagioclase phenocryst 9
Ore Plunge $775 Pit Stretching lineation Average Vein 289/89 Intersection 33° 283° Leapfrog gold grade shells (grey = 1 g/t, yellow = 3 g/t and orange = 5 g/t) with mined out stopes in brown Average Foliation: 109/82 • Boudins and fold axes of auriferous qtz veins, and qtz vein intersections plunge moderate to W corresponding to ore plunge (orthogonal to stretching lineation) 10
$575 Pit $450 Pit Dec 2007 – Mineral Resources* Detour Gold 50,000 m: $575 Pit * Based on a cut-off grade of 0.64 g/t Au, US$575/oz gold price 12