Tanzilla is a non-core project for Kaizen, and is available for sale or joint venture.
Location and ownership
The Tanzilla Project is located in northwest British Columbia, approximately 20 kilometres southeast of the community of Dease Lake. The project is comprised of 26 claims (80 square kilometres/31 square miles) that are 100%-owned by Kaizen.
Tanzilla is situated within the east- to northeast-trending Stikine Arch, where mid-Paleozoic to Middle Jurassic arc volcanic and intrusive rocks host a number of productive porphyry and epithermal systems. The property covers a seven-kilometre-long alteration zone associated with anomalous copper, zinc, lead, gold and silver values in rocks. Previous work identified chalcopyrite-bearing, altered porphyritic intrusive rocks in creek and gulley outcrops near the base of Silica Ridge. Three holes were completed in 2014, one of which (TZ14-05) bottomed in more than 400 metres of intense advanced argillic to phyllic-altered breccia and widespread copper-molybdenum mineralization.
The Silica Ridge lithocap: Porphyry copper occurrences were discovered by West Cirque geologists in a creek bed in the valley floor
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Following the discovery of the Gnat Pass copper deposit in 1960, the extensive alteration in the Tanzilla district was targeted by the West Joint Venture, a consortium of five mining companies, between 1966 and 1970. The work consisted of geological mapping, stream sediment geochemistry, airborne and ground magnetic surveys, trenching and 19 diamond drill holes on the Joyce molybdenum prospect, southeast of the property. Kennecott and Utah Mines conducted several exploration programs in the area in the 1970s, and Uta drilled three holes east of the property on the NUP moly prospect in 1976. In 1989, Equity Silver Mines was drawn to the area by similarities in alteration assemblages with the Equity silver-copper mine, near Houston, central B.C. Equity completed geological, geophysical and geochemical surveys over most of the eastern part of the Tanzilla claims. In 1991, Akiko-Lori Gold completed a reconnaissance mapping, prospecting and sampling program over most of the current property, discovering several previously unknown Cu-Au and polymetallic mineral showings. The property was dormant until the 2003-2008 period when Hyder Gold and Western Keltic conducted mapping and sampling programs.
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Geology and mineralization
In September 2011, West Cirque completed its field program with the primary goal to delineate porphyry drill targets beneath a large advanced argillic lithocap known as Silica Ridge. Previous work by West Cirque had identified chalcopyrite bearing, altered porphyritic intrusive rocks in creek and gulley outcrops near the base of the ridge, supporting the concept of an underlying porphyry system. Additionally, a 17.4 line km induced polarization (IP) survey in 2011 outlined a 2.2 km long by 0.5 to 1.3 km wide chargeability high flanking the ridge.
In 2013, Terraspec aided alteration mapping at Tanzilla confirmed that the central alteration at Silica Ridge and an extension about 3 kilometres to the southeast (Gopher Zone) is dominated by advanced argillic assemblages, including quartz, pyrophyllite, diaspore, alunite, kaolinite, dickite, topaz and dumortierite. Widespread phyllic alteration (quartz, sericite/muscovite, pyrite) is also present on Silica Ridge as well as the Circle Trench zone, one kilometre to the southwest, and the West Gossan zone, about three kilometres to the west.
Following completion of the mapping program, an infill induced polarization survey completed across Silica Ridge confirmed the presence of a strong chargeability high to depths of at least 500 metres below surface. The chargeability high is open to the east and south.
The geological and geophysical data generated by the 2013 program provide further evidence for a large porphyry system centered on the Silica Ridge lithocap. In addition to defining a number of strong coincident IP, structural and alteration anomalies, the program extended the overall size of the system, with advanced argillic alteration being mapped 800 metres north and 2.2 kilometres east of the existing IP grid. The chargeability high centered on Silica Ridge is open to the east, south, and at depth.
2014 drill program
Drill plan for 2014 program at Tanzilla Project, showing large chargeability high. Drill hole TZ14-05 intersected more than 400 metres of advanced argillic and phyllic alteration with associated weak copper-molybdenum mineralization, interpreted as an extensive lithocap over a buried porphyry system.
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The 2014 drill program included three drill holes testing the east, south and north flanks of the Silica Ridge lithocap, and five failed attempts to drill the north side of the lithocap from two setups (TZ14-02A and B, and TZ14-04A, B and C). The three successful drill holes are located 920 to 950 metres apart.
Drill hole TZ14-01 was collared on the east side of the lithocap to test a flanking chargeability high and an area of outcropping diorite porphyry with strong quartz-magnetite veining. TZ14-01 reached a depth of 378 metres, intersecting texturally variable chlorite-magnetite altered microdiorite porphyry overprinted by sericite-pyrite to sericite-chlorite-pyrite (phyllic) alteration. The microdiorite is intruded by a number of syn- to post- mineral diorite to syenite porphyry dikes. Both the chlorite-magnetite and phyllic alteration are associated with minor chalcopyrite and sphalerite and trace bornite. A later set of quartz veins is associated with faulting and intense quartz-sericite-pyrite alteration. Gypsum veins are abundant in the upper part of the hole. Anomalous copper from 36 to 76 metres (324 ppm copper over 40 metres) is associated with a variably textured biotite porphyry dyke cut by copper bearing quartz and gypsum veins. Zinc is also highly anomalous in several sections, including 158 - 206 m (425 ppm over 48 metres).
TZ14-03 was collared on the south flank of Silica Ridge test a chargeability and magnetic high, and the hypothetical depth extension of magnetite and quartz veining with traces of chalcopyrite in outcrops higher on the ridge. TZ14-01 reached a depth 444 metres, intersecting heterogeneous feldspar phyric microdiorite poprhyry which has intruded mafic to intermediate volcanics displaying texturally destructive chlorite-magnetite alteration and minor copper mineralization (as disseminated and vein chalcopyrite). The diorite is also affected by chlorite-magnetite alteration, although generally to a lesser extent. Both of these units have been intruded by post-mineral porphyritic monzonite dykes that display minor propylitic and/or pink hematite alteration. Phyllic alteration locally overprints earlier chlorite-magnetite zones to about 260 metres, where propylitic alteration (chlorite, epidote, pyrite) is more prominent to the end of the hole. From 171 to 189 metres a fragmental rock has been interpreted as a milled dioritic intrusive breccia; it contains minor chalcopyrite toward the lower contact. Fluorite (+ calcite, quartz, chlorite) veins occur between 274 and 354 m. Subtle potassic alteration was encountered from 313 to 321 metres as quartz-biotite + chalcopyrite veinlets. Anomalous copper intervals include 419 ppm copper and 41 ppb gold over 12 metres (254-266 metres) in chlorite-magnetite-chalcopyrite altered feldspar porphyry. The best single assay, 2,480 ppm copper (328-330 metres) is associated with quartz-carbonate-epidote and quartz-chlorite veins with chalcopyrite.
TZ14-05 was collared on the northwest flank of Silica Ridge to test the central chargeability high underlying the lithocap and ended in strong faulting at 476 metres. TZ14-05 was collared in advanced argillic to phyllic altered hydrothermal breccia with relict chlorite-magnetite. At 30 metres depth, feldspar phyric microdiorite porphyry was intersected, variably altered to chlorite-magnetite cut by zones of advanced argillic to phyllic alteration. Multiple vein sets (chlorite-pyrite, quartz-chlorite-magnetite, quartz-clay-pyrite, gypsum) cut the porphyry. A strong fault at 99-101 metres is flanked on the upper / north side by intensely advanced argillic altered hydrothermal breccia. Below the fault, pervasively silicified and oxidized lithocap was intersected between 101 and 146 metres. Below the base of oxidation intensely altered (advanced argillic) hydrothermal breccia with strong multi-phase pyrite veining and replacement and low but persistent levels of high sulfidation copper (chalcocite, covellite) and molybdenum was intersected to the end of the hole. Intervals of phyllic altered cryptic feldspar porphyry occur below 330 metres, suggesting the upper part of the transition to the porphyry style alteration and mineralization. The high sulfidation copper zone averages 356 ppm copper over 284 metres from 184-468 metres (highest value 1,330 ppm). This includes a zone of elevated molybdenum (262-326 m) averaging 90 ppm over 64 metres (highest 807 ppm). The lower part of the molybdenum interval also contains elevated lead (216 ppm over 30 metres, 284-314). Anomalous gold in the upper part of the high sulfidation copper zone, averages 100 ppb over 18 metres (206-224 m). Anomalous values in As are present from 162 metres to the end of the hole. The highest geochemical values are near the bottom of the hole: 20 m from 400 to 420 metres, averaging 755 ppm copper, 53 ppm molybdenum and 52 ppb gold, and 14 metres from 454 to 468 metres, averaging 834 ppm copper, 65 ppm molybdenum and 24 ppb gold.
2015 drill program
Kaizen's 2015 drill program was designed to test to greater depth below and along strike from the 1.5 kilometre-wide Silica Ridge lithocap and associated chargeability anomaly. Three drill holes totalling 1,878 metres were completed, and confirm the conceptual model of a buried porphyry system and associated alteration footprint.
Drilling commenced on July 8, 2015 and ended on August 7, 2015, with a total of 1,878 metres drilled. Results of the widely spaced drilling at Tanzilla to date confirm the conceptual model of a buried calc-alkaline porphyry system with a large footprint. Additional exploration is warranted to vector toward the potentially higher grade core of the system.
Disclosure of a technical or scientific nature on this webpage has been reviewed and approved by John Bradford, M.Sc., P.Geo., who serves as a Qualified Person, as defined under National Instrument 43-101.