In the LCZ area southwest of Tatsamenie Lake, pre-Upper Triassic tuffs, phyllites, siltstones and limestones are underlain by Permian limestones of the Stikine Terrane. These rocks are intruded by plutonic rocks associated with four separate igneous events. These consist of foliated diorite of Triassic age, unfoliated albitite and monzonites of Jurassic and Late Cretaceous ages, respectively, and feldspar porphyry dykes of the Sloko Group of Eocene age. The volcanics and sediments have undergone two phases of folding, a tight isoclinal fold with a horizontal fold axis and an upright more open fold. The early isoclinal phase of folding is associated with thrust faulting, which places Upper Carboniferous felsic phyllites on Permian limestone.
The Jurassic intrusives include a sodium metasomatized variety of diorite composed of albite feldspar. The albite sill is locally mineralized with pyrite, boulangerite and tourmaline.
The Permian limestones consists of a massive, white, thick bedded, grey weathering, recrystallized limestone unit overlain by a dark grey, thin bedded, grey weathering carbonaceous limestone unit. The upper unit contains boudins of chert and/or pyrite.
The limestones are pervasively silicified with local areas of brecciation. The breccia contains large fragments of limestone, banded limestone and phyllite in a dark matrix. Quartz veins commonly occur in the phyllites and dolomitized limestone. Disseminated pyrite is common in these rocks.
The LCZ (Limestone Contact Zone) is a 1.5 kilometre long zone of silicification and brecciation within the Permian limestone. The zone follows the limestone/phyllite thrust contact and consists of a multilithic tectonic breccia with fragments of tuff, limestone and siltstone in a matrix of silica, pyrite and fine black sulphides (Assessment Report 23046). Gold values of up to 7.02 grams per tonne were obtained from samples collected in 1984 (Assessment Report 13068). A 900 by 400 metre gold, arsenic, antimony soil anomaly occurs in the phyllitic siltstone above the contact and is caused, in part, by quartz-sulphide veins within the siltstone. Chevron geologists hypothesized that a manto-like silicified zone was fed by fluids from a vertical feeder zone within the limestones and that there was leakage of fluids into the overlying phyllites. The thrust itself may also have acted as a fluid conduit.
Other mineralization noted in the silicified limestone units includes fracture-controlled and disseminated tetrahedrite and an isolated massive sulphide 'pod' 1 metre in diametre containing galena, sphalerite, pyrite and arsenopyrite. Small, scattered showings of azurite, malachite, chalcopyrite, tetrahedrite and stibnite are indicated on geological maps in the LCZ area, sometimes in association with quartz.
Chevron Canada Resources Ltd (1987) and Armeno Resources Inc (1990) drilled a total of 6 holes to partly test the LCZ trend. Analytical results from drill core yielded 1.38 grams per tonne gold over 4.76 metres, 2.10 grams per tonne gold over 1.75 metres, and 1.30 grams per tonne gold and 68.0 grams per tonne silver over 2.0 metres (Assessment Reports 16528, 20929). None of the holes tested very far downdip and drill spacing is at least 200 metres.
The LCZ zone is truncated at its north end by an east-northeast trending fault around which there exists an area of silicification and dolomitization in limestones that is known as the Tut zone.
Work History
The Ram-Tut-Tot property was first staked in 1981 by Chevron Minerals Ltd. The Tut 1-4 claims covered an area of anomalous silt geochemistry discovered during a reconnaissance program south of the east end of Tatsamenie Lake.
Chevron completed a program of mapping and rock sampling on the property in 1982, when 16 rocks and 96 soils were collected; the previous year 68 rocks and 237 soils were taken.
In 1983, a more thorough program of detailed geological mapping, rock and soil sampling, and minor trenching was conducted. The property was expanded in 1983 with the addition of the Tot 1-4 claims on the north side of Tatsamenie Lake. The Snow 1-6, adjacent to the east the Ram-Tut claims, were staked by Chevron and 207 soils and 24 rock samples were collected.
In 1984, further trenching and sampling was completed by Chevron Canada with 294 rock chip samples taken. W. Hewgill, a student from the University of British Columbia, completed a study of the albitized unit on the Tut claims.
In 1987, Chevron conducted a 674 metre diamond drill program to test the LCZ silicified limestone contact mineralization on the Ram-Tut claims, and a narrow shear zone on the Tot 4 claim. A total of 434.65 metres in 3 NQ drillholes were drilled on the Tut claims. The Ying claim was staked in 1987 to hold tenure in the area of the Tatsamenie Lake Base Camp.
In 1988, the Ram claim was optioned to Shannon Energy Ltd., and on behalf of Shannon Energy, Stetson Resource Management Corp. carried out an exploration program. Seven heavy mineral stream sediment samples were taken, and geological mapping was conducted. Anomalous gold concentrations were obtained from one of the heavy mineral samples.
In 1989, the Ram Baa claim was staked. Chevron and Armeno Resources Inc. entered into an option agreement. Between July and September 1990, Armeno drilled 437.78 metres in four BQ diamond-drill holes to further evaluate the silicified limestone mineralization on the Tut claims. Southernmost drillhole R90-8 was abandoned after penetrating only a few metres of the targeted silicified horizon. Further work included an 11.6 kilometre VLF-EM survey, a 7.2 kilometre ground magnetics survey and the collection of 35 silt, 110 soil and 30 rock samples. A total of 110 soil and 35 rock samples were collected at 50 metre intervals on the Tot claims north of Tatsamenie Lake.
North American Metals Corp (NAMC) acquired 100 per cent interest in the property in 1992, as part of the Asset Sale Agreement between Chevron and North American Metals Corp. (NAMC), prior to the 1992 field season. Homestake Canada Ltd. was contracted by NAMC to carry out the 1992 exploration program during which several known zones were re-evaluated and several new showings were discovered and evaluated. In 1992, 184 rock and 185 soil samples were collected for analysis. Geologists John Bradford and Derek Brown of the provincial Geological Survey Branch mapped the area at a 1:50,000 scale.
In 1994, work on the Tut claims consisted of soil sampling, rock chip sampling and limited geological mapping at a scale of 1:10,000 by owner/operator, North American Metals Corp. A total of 19 soil samples and 45 rock samples were collected from the Tut claims. The work was not applied for assessment. The Ram Baa 4 claim was added in 1994 to cover a fraction between the Tot 4 and Ram Baa claims.
The 2006 Tatsamenie property work program is a Landsat 7 image study that displays significant areas of iron oxide and/or hydroxyl (clay) alteration (Assessment Report 29258). The property is about 6 kilometres north of the past producing Golden Bear Mine and covers twelve mineral showings documented in MINFILE. These showings are the Nie (104K 081), Nie 3 (104K 092), Misty (104K 091), Tut (104K 097), LCZ (104K 080), Honk (104K 122), Tatsamenie Lake (104K 038), Barron (104K 120), Patella (104K 134), Backbone (104K 135), Shoulder (104K 136), and LCZ Extension (MINFILE 104K 137).
In 2007, on behalf of Nakina Resource Inc, Geotronics Consulting conducted a Mobile Metal Ion soil geochemical survey, collecting 420 MMI soil samples. The distance between the southern limit of the LCZ mineralized trend (104K 097) and the relatively new LCZ Extension (104K 137) is a further one kilometre to the south. This represents a distance of approximately 2 kilometres of potential gold bearing mineralized ground. The 2007 grid was laid out in that largely unexplored area between the LCZ trend and the LCZ Extension zone. The grid area was mapped previously phyllite. The 2007 Mobile Metal Ion soil sampling survey in the LZC Extension area defined a broad zone of highly anomalous gold and associated anomalous elements that extended to the grids north, south and eastern limits.
In 2008, on behalf of Nakina Resource Inc, Geotronics Consulting conducted a Mobile Metal Ion soil geo chemical survey, collecting 663 MMI soil samples. Work also consisted of an induced polarization survey on the same grid, and a magnetic survey totaling 11.5 kilometres. MMI anomalies A and B are reported with IP survey correlation. The work was mainly confined in LCZ extension area.
In 2010, on behalf of Nakina Resource Inc, Geotronics Consulting conducted a Mobile Metal Ion soil geo chemical survey, collecting 663 MMI soil samples. Work also consisted of a 9.9 kilometre induced polarization survey and an 18.4 kilometre ground magnetic survey. The anomalies have been grouped into five anomalies, or anomalous zones, labeled by the upper case letters, A to E, respectively. Three of these have been defined by gold anomalous results, and include anomalies A, C, and E; the other two have been delineated by copper anomalous results and include anomalies B and D. Four of the MMI anomalies A to D inclusive, show strong correlations with IP anomalous results which indicate the causative sources to be sulphides, probably base metal. In general, the MMI results indicate that mineralization occurs over a wide area and the mineralization is zoned. The work was done mostly in the area around and immediately north of the LCZ Extension showing, extending towards the LCZ trend area. The grid falls just short of the LCZ trend zone.
In 2020, Brixton Metals Corporation completed a program of geochemical (rock and soil) sampling, a 12.5 line-kilometre ground induced polarization survey, a 715 line-kilometre airborne magnetic and electromagnetic survey and 19 diamond drill holes, totalling 5292 metres, on the area of as part of the Thorn property. Drilling was performed on the Outlaw (MINFILE 104K 176) occurrence area.