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The Olympic-Rob properties covers a portion of the Coal Creek Inlier, an oval shaped erosional window of Middle to Late Proterozoic sediments and carbonates of the Wernecke Supergroup.
Hematitic breccias underlie close to 10 square kilometres of the Olympic property. These breccias form large, continuous units that locally contain very large fragments up to 10 metres and occasionally larger in size. Interpretation of the geology indicates portions of the Olympic property have undergone extensive, very high energy, episodic breccia formation as evidenced from the areal extent of the breccia complex, the polymictic nature and variable clast sizes of the fragments and the differing compositions of the matrices. That most of the breccias observed are mainly matrix supported indicates that a very large volume of chlorite, hematite and carbonate was introduced during breccia formation. The high frequency of angular, largely unaltered fragments plus the composition of the matrices also points to a rapid and vigorous, rather low temperature event. This environment is analogous to parts of the unmineralized breccia complexes that exist at the Olympic Dam deposit in Australia and is considered a highly favourable host for copper, gold and uranium enriched mineralization.
Mineralization observed on the Olympic property during the 1997 mapping program was mainly comprised of chalcopyrite, chalcocite, pyrite and magnetite. On the Rob prospect, uranium accompanies some copper zones. Copper mineralization, often in the form of chalcopyrite with some bornite and chalcocite, was noted as being strongly associated with the intensity of brecciation and alteration (i.e. matrix composition). Within the breccias chalcopyrite occurs within veins and veinlets crosscutting both matrix and clasts, as disseminations in the matrix, fracture fillings and as coarse clots associated within carbonate infillings. Chalcopyrite also occurs as fracture fillings, veins, and clots within the mafic dykes and along silica filled fractures in zones of intense silicification. Sericite alteration accompanies copper mineralization west of the graben, indicating a possible closer source to the centre of copper mineralization.
The Proterozoic sediments are disrupted by an extensive iron-rich multi-phased breccia complex covering 10 sq km. This irregular shaped breccia is up to 7,000 metres long and has been traced to depths of greater than 400 metres. The breccia complex is characterized by a large, complex magnetic anomaly. Several regional-scale east-west thrust (growth) faults and a steeper northeast-trending graben structure transect the property. Intersections of these faults create large zones of dilation that are prime locations for ore accumulation. Breccias on the Rob property are largely carbonate matrix with strongly milled wall rocks and hematite alteration. Some semi-massive magnetite was found within hematite rich, matrix supported breccias. Locally, disseminated chalcopyrite, bornite and pitchblende was observed in the breccia matrix
Widespread copper mineralization occurs within the matrix of the high energy, low temperature breccia bodies and along fractures. Majority of the samples returning significant copper values were from the western portion of the magnetic anomaly. The more significant samples reported assays of 5.0% Cu/1.5 metres, 7.0% Cu/4 metres and up to 21.4% Cu from chip samples. Copper minerals identified are chalcopyrite, bornite, chalcocite and malachite. Copper minerals are usually accompanied by potassium enriched sericite.
The initial mapping program focused on the central area of the Olympic claim block. Subsequently, the IP survey revealed that weak to moderate en-echelon chargeability responses ranging from 1,500 metres long by 100-400 metres wide occur along the northern flank of the western magnetic high as well as coincident with the northern portion of a large northeast trending graben structure.
The 1997 drill program was conducted to test anomalous IP chargeabilities, within or immediately adjacent to the central graben structure. It confirmed that an enormous extent of multi-episodic, variably altered iron-rich breccias with contemporaneous intrusive dykes occur on the Olympic property within a structural environment favourable for the formation of Olympic Dam style mineralization. Evidence of anomalous copper was also observed in three separate drill holes that returned values of 0.27% Cu over 9.0 metres, 0.20% Cu over 6.0 metres and 0.12% Cu over 2.8 metres. All of these elevated copper values were found to exist to the west of the main graben structure as evidenced by a strong boundary fault. All holes drilled westward through this fault were lost due to squeezing in the fault zone.
The drill results also indicate that the areas tested to date may represent distal / high level and lower temperature environments within such a mineralized system. This conclusion is based on the following observations: pervasive silica flooding or capping in the area of north central portion of the graben structure; copper mineralization predominantly associated with quartz and quartz-carbonate veining as well as fracture filling as opposed to more disseminated and replacement type mineralization; evidence of frequent, large sized blocks or rafts of non-brecciated material indicative of a marginal phase of tectonism as evidenced in the northeast portion of the area tested; much less copper mineralization occurring in the vicinity of the valley floor than that indicated by previous surface surveys on the hillsides mainly to the west of the Pyramid Creek Valley.
Structural information gathered from the drilling program supports the idea that the area of the Pyramid Creek Valley is the down dropped, upper section of a major graben feature. Based on this information it is conceivable that at the time of mineralization the magnetic source underlying the valley floor may have been at or near the same structural level as the showings along the topographically higher hillsides to the west and east. Later normal movement along the older basement faults resulted in the down-dropping of the lower temperature, less mineralized upper portions of the breccia complex to the topographic position seen today.
Due to increased breccia intensity and alteration, high grade copper showings and the presence of anomalous Ba, Fe, F, K2O, Na2O and REE'S, west of the main graben structure, this area represents the most attractive exploration opportunity on the property at present. Three to four square kilometres of the breccia complex are mapped in this western target area that has not been drilled.
In 2007, Fjordland Exploration completed one diamond drill hole to a depth of 306 m. The hole was spotted down-slope from copper mineralized breccia exposed in outcrop. The mineralized zone was not reached. Attitude of the zone is not apparent on surface. Based on available drill data, it appears to be more steeply dipping than the Graben Fault. Two holes are planned to step forward from hole 97-04 to test for the depth and extent of mineralization exposed at surface.
2009 NEW TARGETS
A site visit in early 2009 resulted in discovery of a large zone of previously unrecognized copper mineralization. Extensive malachite was seen on steep slopes and cliff faces in the most southwesterly portion of the hematite breccia complext west of the graben fault. The malachite stain areas (Lesley Showing) measure roughly 200m by 250m in extent and were not likely previously seen due to very steep slopes just below cliffs on the ridge top. Soil samples taken below this area by UMEX in 1977 ran up to 18,000 ppm Cu.
A brief toe-in helicopter landing was made in one location, indicating a fine grained intrusive breccia was a local host to copper mineralization. Several strong sericite altered samples ran 0.2 to 0.5% Cu. Several photos of the Lesley Showing are below.
Recent re-interpretation of the ground magnetic data has shown the presence of two large, buried magnetic bodies. One body of about 700 metres diameter is buried 200 metres deep in the central portion of the Pyramid Valley Breccia Complex. The second body is elongate, measuring 400 metres wide and over 1600 metres long, trending southern-westerly from the SW part of Pyramid Valley. As the magnetic character of these bodies is quite different it is considered that they are not connected. The extensive, new Leslie copper showings are situated above the western end of this body, which is at least 400 metres deep.
These new magnetic targets have not been drill tested. The position of the newly revealed magnetic bodies is shown on the plan map (below) and two cross-sections, which also show relative position of the extensive Leslie showings.
Total expenditures to date ~ $2.5 million
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