Kincora Copper Limited is pleased to provide an overview on our internal interpretations of last years exploration programme at our flagship Bronze Fox license having integrated them with previous geology and geophysical results.
This follows the recent receipt of positive findings from three independent consultants, further reinforcing an independent groups' technical review late 2012, advancing and refining multiple bulk tonnage copper porphyry targets.
Copper-gold porphyry targets refined and de-risked
Since 2010, Kincora has undertaken soil geochemistry, Vector IP and some sections of DDIP, ground magnetic surveys, and drilled a further 70 holes inside of the Bronze Fox license area. Drilling has expanded the known mineralization footprint to about 40km2, remaining open, confirming porphyry style of copper-gold resource potential with extensive lower grade intersections from at or near surface and proven to 1,360 metres. Results of the last drilling programme, in late 2012 were extremely encouraging with a number of porphyry intersections confirming the potential for a high-grade deposit (localized +4% Cu in our last hole - F72 - drilled into a new target area based upon then recent IP analysis) with broad lower grade (eg +800m @ +0.40%CuEq, including 37m @ greater than 1% CuEq - F62) intersections.
Various lithogeochemcial and petrographic analysis undertaken in 2013, including extensive sampling and site visits, has independently supported that Bronze Fox is in the same tectonic and arc environment as Oyu Tolgoi and Tsagaan Suvarga, and increased the confidence that Kincora is exploring in the right terrain, or a fertile arc, at our various prospects, and prospects targeted in 2014, encouraging further exploration. The porphyry fertile signatures and visual interpretation of core inspected indicated that the current drilling concentration area at the West Kasulu prospect is possibly the distal peripheral of a porphyry system, the later interpreted to be within a relatively short distance of this previous drilling concentration area in the Bronze Fox license. This analysis also indicates a geochemical footprint across multiple prospects at Bronze Fox that matches other major globally significant porphyry deposits.
Previous geology and geophysics supported the potential of a copper-gold resource. Indeed early stage studies had commenced on a potentially small scale near production heap-leach SX-EW operation utilising near surface oxide mineralization, and deeper drilling results at the end of the 2012 confirmed the potential for high-grade copper porphyry mineralization. However, the lack of IP data below 400 metres depth, and only in certain areas, limited the ability to reconcile previous drilling and indications of significant scale hydrothermal fluids that support potential concealed higher grade copper porphyry mineralization. Given the limited zones of outcropping primary mineralization, known regional (block) faulting and target of Oyu Tolgoi ('OT') or finger porphyry style copper systems, Induced Polarization, coupled with existing magnetics, has been proven to be an effective exploration tool when integrated with proper geological information and interpretation. The success of similar IP programmes at OT and the technical successes experienced by Kincora in late 2012, with drilling at previous IP anomalies returning alteration, sulfides and copper mineralization (+4% localized copper intersection in F72), adds significant substance to IP analysis particularly given existing geological data available at Bronze Fox, which is one of the most advance copper exploration projects in Mongolia.
OT style mineralization generally features relatively narrow (comparing with North and South American porphyries), long strike orebodies, and good extension to depth. As such, the Search IP system, utilized in the 2013 IP survey, which has penetrated to over 800m to 1000m, was selected as the optimal tool to assist locating the mineralization or alteration zone with disseminated sulfides (which is normal for porphyry mineralization) with good extension to depth which may indicate disseminated pyrite/sulfides channels, and support the possibility of ore mineralization based on the comparison of previous drilling results and the distribution of the IP chargeability anomalies. It is thought that those mineralization or alteration zones with good extension to depth have a better chance to host higher-grade mineralization, and economic orebodies.
At Bronze Fox, the 2013 IP analysis illustrates that prior drilling failed to adequately test most large chargeability high anomalies with previous encountered mineralization coincident with lower priority IP chargeability zones. Prior to the 2013 programme earlier geophysics could not provide an adequate guide for either depth extension potential of identified mineralized zones nor for targets below 400m below surface, with drilling being largely lead from encouraging mineralization encountered in previous core. For example the aforementioned holes, F62 and F72, illustrate the grade of CuEq and IP chargeability co-relationship, which support that high chargeability is coincident with sulfides of mineralization zones. The new IP results coupled with the latest alteration and veining studies have "explained" previous results, particularly the extensive 0.20 to +0.30% copper intersections to date, and lead to a reinterpretation and refinement of targets. In F62, over 800m graded at least 0.4% CuEq with subsequent IP analysis indicating the hole only interested the periphery of a relatively weak anomaly target (noting higher grades, including 37m @ +1%CuEq, were coincident with being within less than 500m from the interpreted IP anomaly zone) and subsequent alteration and veining studies indicate a less prospective portion of the interpreted porphyry system. The application of the 2013 Search IP programme, coupled with existing geology and geophysics, and independent analysis undertaken by Professor Tony Crawford and Plus Minerals (Imants Kavalieris) has advanced and refined target generation.
A number of analogies between the current stage of exploration and results at Bronze Fox and Oyu Tolgoi pre "discovery hole" have emerged after our 2013 field season, including geophysical anomalies remaining largely untested with favourable mineralization coincident nearer surface and lower priority IP targets. At Oyu Tolgoi, previous BHP and Ivanhoe drilling failed to reach the geophysical targets, with a change in exploration approach to test the geophysical and hypogene potential resulting in OTD 150, between previous shallow holes (BHP 9 and BHP 10), being the first 'deep' hole and credited as the "discovery hole".
At Bronze Fox nine drilling target zones have been identified following the latest IP survey results being integrated with geology, soil geochemistry, rock chip assay result, ground magnetic survey and historical drilling results. IP survey results illustrate multiple significant strike (+1-2km) chargeability high anomalies with good extension to depth that may indicate disseminated pyrite/sulfides channels.
Two targets of particular note are:
- Sophie North - a classical geophysical circular feature ~2km x 3km from an estimated ~300-500m depth to +900m. Previous drilling failed to enter IP target zones but returned anomalous copper and gold mineralisation (holes lost in an alteration zone).
- Eastern West Kasulu/Leca Pass - Numerous holes close to IP targets have returned favourable grades but have failed to test the target zone. Multiple specific +1-1.5km anomalies targeted for potential drilling with regional scout holes and geology providing favourable results.
Successful "proof of concept" activities at the identified targets, including Sophie North and Eastern West Kasulu/Leca Pass, with economic grade (or high grade) intersections, could support a significant copper ore resource. Collectively there is large-scale copper-gold resource potential which is one of the underlying attractions of Bronze Fox. Previous phases of exploration have been favourable, refined and de-risked target generation, and while there is no certainty of exploration success, numerous drill ready targets have been defined, with few other activities that could meaningfully further de-risk these targets (ex-Happy Geo, discussed further below) based on previous experience at Bronze Fox and other porphyry exploration projects.