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| | | Download Storm Property Summary (PDF 1.17mb) Storm Copper Property, 43-101 Technical Report, February, 2009 (PDF 2.59mb) OVERVIEW
It is located on the northwest corner of Somerset Island, Nunavut. The Seal zinc-silver zone sits on tidewater on a Peninsula that extends into Aston Bay. The Storm Copper area is located approximately 20 kilometres inland from the Seal zone. The property is well-located in a flat region that has access to tidewater and shipping lanes. The hamlet of Resolute Bay is the closest aerodrome located about 150 kilometres to the north on Cornwallis Island. Resolute would be the staging area for work here and provides reasonably good services. The entire property area was acquired by Commander in 2008 through the award of three Prospecting Permits, which are valid for a term of five years. The total cost of the acquisition was $15,021.32. This money will be refunded upon completion of an equivalent amount of exploration work within the first two years. HISTORY Work over the years on the property and larger land area of northern Somerset included airborne magnetic and electromagnetic surveys, extensive soil geochemistry, ground geophysics (IP, HLEM and UTEM) and diamond drilling. Historical work on Seal
Historical Work on Storm
HISTORY Work over the years on the property and larger land area of northern Somerset included airborne magnetic and electromagnetic surveys, extensive soil geochemistry, ground geophysics (IP, HLEM and UTEM) and diamond drilling. Historical work on Seal
Historical Work on Storm
Sedimentary Copper deposits
Examples of deposits in this class include Kipushi (70 Mt @ 4.8% Cu, 8.8% Zn, 0.5% Pb), Kennecott (4.4 Mt @ 12.4% Cu, 95 g/t Ag), Ruby Creek (90 Mt @ 1.2% Cu). Gross metal values can be very high in these deposits. Individual deposits can be pipe-like to tabular and are often irregular and discordant with strong elongation in one direction. Deposits can be up to several hundred metres in size and can be associated with Zn rich lenses, pods or deposits nearby. Copper mineralization is zoned vertically in many deposits with the more copper rich phases (chalcocite, bornite) closest to surface. The Storm copper property contains most of the large and small-scale attributes and characteristics that are typical of this class of deposit PROPERTY DETAILS
Pre-mineralization structures at Storm include large scale dilational faults and brittle fractures in the Silurian Allen Bay carbonates beneath more ductile sediments (Cape Storm Formation) - the geometry of the structural trend supports the possibility that a basement shear led to intense dilation, brecciation and faulting in the overlying brittle carbonates. A large graben, which is central to the copper mineralized trend, may have formed in response to dissolution and collapse related to fluid movements along the pre-existing structures and the Cape Storm Formation may have acted as a cap containing the mineralizing fluids in the upper parts of the Allen Bay carbonates. The underlying Proterozoic basement rocks, well exposed on the coast, include a thick red-bed sequence that may have provided metals for both the copper and zinc mineralization. The Paleozoic basin on northern Somerset Island contains evaporites and younger red-bed sequences that may also have been contributory to mineralization. The upper Allen Bay Formation was divided by Cominco Ltd into three distinctive units starting immediately beneath the Cape Storm Formation contact (see section below for unit descriptions). The ADMW unit is underlain by the BPF unit, which is underlain by the VSM unit. The geological terminology used is taken from assessment reports filed by Cominco and conforms to standard carbonate geology nomenclature. The Cape Storm Formation overlies the Allen Bay Formation comformably, but contains no significant copper mineralization. However, the Douro Formation overlying the Cape Storm Formation is a nodular, fossiliferous limestone unit that locally contains copper mineralization. Allen Bay Stratigraphy The BPF, distinguished by its medium to dark brown and different lithology, is the dominant host of good copper mineralization throughout the property. It is within this unit that the best replacement textures are seen. Though most of the mineralization was hosted in the Allen Bay, hole ST99-35 intersected 0.85% Cu / 1.8 metres in the Douro Formation fossiliferous limestone. This indicates potential may exist in the Douro Formation, a unit not considered as a good target prior to the drilling. Allen Bay Stratigraphy The BPF is the dominant host of good copper mineralization throughout the property. It is within this unit that the best replacement textures are seen. The fossiliferous and bioturbated nature of the BBF provides a receptive host for mineralization fluids. Adjacent to strongly mineralized BPF, the ADMW unit usually contains moderate crackle breccia hosted and stringer/vein style mineralization throughout, often extending up to the contact with the Cape Storm Formation. Only in the 3500 Zone is mineralization seen to penetrate down into the VSM, likely due to the structurally complex nature of this area. The best mineralization in the 3500N zone is BPF as breccia cement and towards the top of the VSM as stringers. Through most of the mineralization was hosted in the Allen Bay, hole ST99-35 intersected 0.85% Cu / 1.8 metres in the Douro Formation fossiliferous limestone. This indicates potential may exist in the Douro Formation, a unit not considered as a good target prior to the drilling. ADMW unit (Alternating Dolmicrite and Dolwackestone) The ADMW unit consists of a 35-50 metre succession of fine-grained dolomitic mudstone (dolmicrite) alternating with light to medium grey silty dolomite intervals containing disseminated fossil fragments and debris (dolwackestone). The base of the ADMW is marked by the first appearance of the BPF unit. BPF unit (Brown Dolpackstone and Dolfloatstone) The BPF unit is distinguished by its medium to dark brown and different lithology. Dolpackstone is a term defining a fossiliferous unit where the concentration of fossil fragments is very high such that individual fossil fragments are packed together cemented by carbonate. The unit averages approximately 35 metres in thickness. Chert nodules are common in this unit and seem to be restricted to two horizons, one found about a third of the way from the top, and the other located close to the base. The bottom of this unit is marked by the appearance of light grey to buff stromatoporoid facies. VSM Unit (Varied Stromatoporoid) The VSM unit is composed of various dolfloatstone and dolrudstone beds (term that defines coarse fossil fragments that produce a cobble texture), interbedded stromatoporiod boundstone, framestone, and some thinly bedded dolmicrite beds. The unit is greater than 150 metres thick. Close to the top of the VSM unit is a distinctive reef horizon, the SBFM unit (Stromatoporoid Boundstone/Framestone Marker). The distinctive marker is characterized by digitate stromatporoids in growth position. Dolarenite and dolmicrite sediments fill the interdigitate voids. The SBFM marker averages six metres thick, though in places is found brecciated, and significantly thinner. Five metres below the SBFM is the RCM unit (Rudstone Chip Marker). The RCM is less than one metre thick, consisting of a shelly hash of elongate fossil fragments. In the western portion of the property, a third marker unit, the OP (Oolite Marker), occurs about 40 metres from the top of the VSM. This distinctive marker is composed of one or two reverse-graded oolite to oncolitic packstone beds. In the 3500 Zone the SBFM and RCM are located roughly 35 metres below the Oolite Marker, demonstrating substantial thickening of the VSM to the west. The SBFM and RCM markers occur within the footwall to most of the mineralization and represent a useful level past which drilling was terminated. The SBFM and RCM were found across the drilled area, but not in every hole. This was due to holes collared in the footwall, 2) the late recognition of the markers in the program 3) a lack of significant mineralization above that level in many holes and, 4) holes lost at a shallow depth. This stratigraphy was identified best in the 4100 Zone where are a number of closely spaced holes intersected the marker horizons. The OP is dominant in the 3500 Zone. However both the SBFM and RCM markers were located on the eastern edge of the 3500 Zone (Hole ST99-38) allowing the 3500 zone to be placed in the regional context. The stratigraphic subdivision and the two markers (SBFM and RCM) provide important information for regional evaluation of the Allen Bay Formation. Stratigraphic Column - Storm Copper  Back
Four zones of significant copper mineralization were discovered and tested between 1997 and 2000.
The zones named 2750N, 3500N, 4100N and 2750N contain locally high-grade intervals of chalcocite (79.85% Cu), bornite (63.31% Cu) and chalcopyrite (34.63% Cu) with local concentrations of accessory minerals, covellite (66.46% Cu), native copper, cuprite, malachite and azurite. Pyrite and marcasite occur as the main non-copper sulphides. The mineralization is hosted within the upper 80 metres of the Silurian Allen Bay Formation dolostone close to the conformable contact with the overlying Cape Storm Formation. Zone 4100 N Ground EM further defined the zone and led to additional drilling by Noranda in 2000 and led to drilling of an additional six (6) holes in 2000 (holes ST-00-60 thru ST-00-65). Mineralization in the zone extends over an area of at least 1000 metres x 400 metres and is open to the north and east, with some potential for deep extensions of the zone across the 4100 fault to the south. The mineralization drilled to date indicates an erratic, but consistent zone of mineralization within a predictable stratigraphic position, but with a trend and orientation that is not clearly understood. More details and drill results
Zone 2750N The surface expression of the 2750 Zone consists of an east-west trending copper oxide gossan with abundant copper sulphide mineralization and malachite staining. The initial hole drilled on the zone was ST97-08, which intersected 2.92% Cu over 105 metres, including 53.9 metres grading 5.09% Cu (Drill Results). Hole ST97-09 drilled to the south as a scissor cut across the zone hit 2.65% Cu over a true width of 24.6 metres. In follow-up drilling, additional holes demonstrated that a small, high grade zone was present. A near-surface hematite-cemented breccia unit correlated well with surface rubble. Several significant high-grade intervals with replacement, stratabound textures were intersected in the zone. The trend of this zone has not been fully tested and the high grades suggest the opportunity for a small, but very high grade zone that could be contributory to a larger property resource portfolio.
3500N Zone Surface copper mineralization and rusty, limonitic, recrystallized Allen Bay Formation outcrop as rubble and subcrop over a 300 metres strike length between 2400E and 2700E in the area of 3700N. The mineralization occurs within a complex of intersecting faults and lineaments, related to the overall structural corridor. The nature and extent of the surface mineralization was tested with eight holes from six drill collars. (Drill results) Two of the holes intersected moderate grade copper mineralization over a strike length of 200 metres. Hole ST99-31 intersected 2.2% Cu / 12.6 metres between 7.6 and 20.2 metres and 2.9% Cu 9.2 metres between 26.6 and 35.8 metres as disseminations, stringers and veins within recrystallized dolostone. While chalcocite and bornite dominated the copper phases, narrow widths containing cuprite in vuggy dolostone were noted, a product of meteoric groundwater circulation. Hole ST99-33 drilled from the same collar at a steeper angle returned 1% Cu / 4.8 metres as the best result. It failed to intersect the mineralization in hole 31 indicating a fairly erratic and discontinuous zone. Stepping out 90 metres to the west of hole 31, hole 43 tested the same surface mineralization as 31. Similar copper mineralization was intersected across the same widths as intersections in 31, but at a lower grade. The best result from 43 was 1.58% Cu / 11.8 metres (41.0-52.8 m). Additional step-out holes to the east and west included ST99-28, 30, 38 and 41 all of which failed to intersect significant high-grade copper mineralization. 2200N Zone The 2200N Zone outcrops along a ridge that tops the river valley. Abundant copper mineralization in outcrop and felsenmeer was mapped over several hundred metres. Shallow drilling in 1997 intersected high grade copper mineralization from surface to a depth of 50 metres but over a relatively limited strike length. Bornite and chalcocite are the dominant sulphides. (Drill results)
Several types of breccias were preserved in the system, dominated by crackle and mosaic breccias, locally cemented by sulphides. Local solution-rounding and dissolution was observed in areas of more concentrated mineralization. The 4100N zone contains a consistent interval of copper mineralization that extends over a broad area that has not been closed off. A significant area of mineralization grading in excess of 1% Cu includes local high-grade areas that indicate the potential for a significant resource. back Zone 4100 N Ground EM further defined the zone and led to additional drilling by Noranda in 2000 and led to drilling of an additional six (6) holes in 2000 (holes ST-00-60 thru ST-00-65). Mineralization in the zone extends over an area of at least 1000 metres x 400 metres and is open to the north and east, with some potential for deep extensions of the zone across the 4100 fault to the south. The mineralization drilled to date indicates an erratic, but consistent zone of mineralization within a predictable stratigraphic position, but with a trend and orientation that is not clearly understood. More details and drill results
Table presenting the copper intervals for all holes drilled. Mineralization in the zone extends over an area of at least 1000 metres x 400 metres and is open to the north and east, with some potential for deep extensions of the zone across the 4100 fault to the south. The mineralization drilled to date indicates an erratic, but consistent zone of mineralization within a predictable stratigraphic position, but with a trend and orientation that is not clearly understood. The zone is dominated by chalcocite and bornite occurring as, 1) near-vertical to steeply south-dipping vein and breccia systems and, 2) as stratabound disseminations, void fill and replacement of organic partings and macrofossils. Chalcopyrite is of lesser importance, but may have been replaced by the high Cu species. Native copper, associated with pervasive limonitic alteration, was intersected at a deeper level. All holes drilled in the zone intersected variable copper mineralization of similar texture and style within the same stratigraphic interval over a total strike length in excess of one kilometre. Copper mineralization extends over a considerable stratigraphic interval including the basal, hematite altered Cape Storm Formation. All of the significant copper mineralization occurs above within the BPF and ADMW units above the SBFM and RCM markers (see stratigraphic unit definitions below). A crude zonation in copper mineralization (top to bottom) from chalcocite>bornite>chalcopyrite>Native Cu is evident in the zone, which is also similar to other known copper zones at Storm (i.e. 3500 North Zone) and in similar deposits. Upper portions of the system are predominantly fracture/vein controlled but appear to be interconnected. Copper mineralization is dominantly chalcocite, which forms near vertically dipping vein and breccia systems, with some heavy disseminated sections and locally void fill and fossil replacements. Local high Cu grades were returned from local intervals characterized by elevated amounts of matrix (breccia cement) sulphides. The lower, low grade Native Cu-rich interval is also fracture/vein controlled. A zone of weak galena+sphalerite+chalcopyrite mineralization (predominantly as veinlets/fracture fillings and disseminations) occurs below the main zone of copper mineralization hosted in a porous and fossiliferous unit. This mineralization appears to reflect an outer (lower temperature) Pb-Zn zone adjacent to copper mineralization. An upper marcasite-pyrite dominated zone grading downward into a pyrite-chalcopyrite zone was observed in some areas. Previous. All pages. Next. Page 1. Page 2 Previous. All pages. Next. Page 1. Page 2 | ||||||||||||||||||||||||||||||||||||||
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