お知らせ • Jun 10
Coda Minerals Limited Reports Results from Recently Completed Geophysical Programmes at Its Highly Prospective Cameron River Project, Located in the Heart of the World-Class Mt Isa Mineral Province in North Queensland
Coda Minerals Limited reported results from recently completed geophysical programmes at its highly prospective Cameron River Project, located in the heart of the world-class Mt Isa mineral province in North Queensland. Cameron River comprises 35km2 of copper and gold exploration tenure immediately north of the historical Mary Kathleen Uranium Mine. In March 2021, the Company entered in a binding Farm-In and Joint Venture Agreement giving it the right to acquire up to an 80% ownership in the Cameron River Project. Final geophysical survey results have been received for the IP programme comprising three grids of Gradient Array Induced Polarisation (GAIP) and a single line of Dipole-Dipole Induced Polarisation (DDIP) which commenced at Cameron River on April 3rd of this year. The IP surveys targeted the company's key prospects: Copper Weed, Rebound, Bluey and Bingo and their associated mineralised trends, identified by field mapping. Preliminary results of these surveys were reported on April 22nd, with the full results now available. GAIP has identified numerous chargeability anomaly trends, several of which are associated with mapped malachite and/or geochemically anomalous rock chip samples. The most prominent of these are the Copper Weed and Rebound trends, two chargeability trends extending approximately 2km north and 1.6km north northeast respectively from a common starting point in the south of the tenure. Both trends have extensive mapped malachite occurrences at various points and are associated with numerous high grade rock chips, both modern and historic. Additional IP anomalies, including a significant conductivity anomaly at the Bluey prospect, were also identified. Based on these results, a single line of DDIP was designed to cover both trends, passing from an area south of Copper Weed to east of Rebound. Inversion modelling of the DDIP data identified four prominent shallow chargeability anomalies, each associated with trends identified in GAIP and surface geochemistry. From east to west these are: Copper Weed Trend: With a peak chargeability of >27.5 msec at approximately 95m below the surface, this anomaly is located due south of the Copper Weed prospect and is associated with a major trend identified in GAIP as well as extensive mapped malachite. Rebound 1 Trend: Though the least intense and deepest (peak chargeability of >15 msec at approximately 140m below surface) of the three Anomalies, Rebound 1 has the strongest association with both mapped malachite and numerous high grade copper and gold bearing rock chips, including sample R22CR0102. Rebound 2 Trend: The most prominent anomaly along the DDIP survey line, this anomaly peaks at >47.5 msec and is located at approximately 90m below the surface (depth to top). GAIP has identified a local trend extending approximately 500m NNE/SSW, associated with some extremely high-grade rock chips, but work in the area has been relatively scarce. This anomaly is among Coda's highest priority targets for upcoming drilling, anticipated in August 2022. Rebound 3 Trend: The second very high intensity shallow anomaly identified on the DDIP line (>32.5 msec, approximately 75m below the surface), Rebound 3 is associated with a local peak in an extensive (>2,300m) chargeability anomaly that the company had previously believed to be stratigraphic or associated with large scale shearing. However, a high-grade historical rock chip (8% Cu) is located less than 90m south of the DDIP line at this point, making this another high priority target for future drilling. The recently completed GAIP survey was designed to test three priority target areas at Cameron River, the Copper Weed and Rebound prospects, as well as the recently identified Bluey/Bingo trend. GAIP is a geophysical technique whereby an electrical current is passed through the subsurface in between two transmitters located outside of the survey area, inducing an electrical charge in disseminated electrically conductive minerals such as sulphides. Results from the survey highlighted several significant trends of chargeability within the target areas, many associated with known prospects, but some, such as the Clifford prospect, resulting in the delineation of new, highly priority targets which were then assessed by field mapping and sampling. The copper mineralisation at Rebound is clearly reflected in the IP as a moderate chargeability anomaly, increasing in intensity towards the south, with an associated moderate conductivity anomaly over approximately 500m of strike. At the southern end of this trend is a coincident elliptical high-conductivity anomaly and moderate chargeability anomaly, associated with local historic rock chips of >1% Cu. Additionally, a north trending high chargeability feature (the "Copper Weed Anomaly") has been identified, corresponding with both a magnetic high and the trend of the historic Copper Weed artisanal workings. Mapped malachite appears to flank either side of the peak of the chargeability trend, and historic rock chip samples taken from several points along this trend have reported results of up to 22% Cu. The chargeability anomaly may in fact represent two separate anomalies, with the northern NNW trending portion consistent with topography suggesting a stratigraphic response, while the southern portion reorients to SSW and is consistent with a trend of mapped malachite to the west of the ridge at Copper Weed, suggesting a non stratigraphic source. The company considers the more southerly portion of the anomalism to be a high priority target for further work. Magnetic data supported by geological mapping suggest that the chargeability response and interpreted mineralisation are associated with fault splays feeding north off the regional Cameron Fault, acting as conduits for mineralising fluid, while marble and recrystallised limestone units within the geological package are a focus for deposition with minor to moderate copper mineralisation occurring in the rocks adjacent to the carbonate units. Intensity of alteration and mineralisation increased southwards with proximity to the Cameron Fault. A small number of conductivity anomalies were identified through the survey, but most have been identified to represent stratigraphic responses of little economic interest. One anomaly in the far northwest of the survey area is of far greater significance. By far the most conductive material within the survey area, the discrete anomalism is at least 500m long (extending to the edge of the survey area) and is associated with the large central ridge at the prospect, which has previously identified numerous conductivity anomalies through historical VTEM surveys, each with significant multielemental geochemical signatures suggesting economic potential. The newly identified conductive material appears to lie below cover, and has been tested through biogeochemistry.
