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Occurrence Details


Occurrence Number
106C 106
Occurrence Name
Malbec
Occurrence Type
Hard-rock
Status
Prospect


General Information

Secondary Commodities: gold, arsenic, mercury, antimony, thallium
Aliases: Shiraz, Crag East
Deposit Type(s): Carbonate-Hosted Disseminated Au-Ag (Carlin-type)
Location(s): 64.061990 N, -132.547880 W
NTS Mapsheet(s): 106C02
Location Comments: Approximate mid point of Malbec zone.
Hand Samples Available at YGS: No

Capsule

WORK HISTORY

Staked within Crag cl 402 – 677 (YE13490) in Mar/2011 by Strategic Metals Ltd. The property was named Crag East to differentiate it from the Crag property (claims) located to the west. Both properties are included within Strategic Metals larger regional Midas Touch project.
 
In 2011 Strategic Metals prospected and carried out reconnaissance soil and silt sampling which was followed up with prospecting, geological mapping and detailed soil sampling. Later in the summer the company collared 6 diamond drill holes (1 398.73 m) on the property. Two of the holes (384.05 m) tested the newly discovered Shiraz zone.
 
In Aug/2011 the company staked Crag cl 678 – 813 (YE64458) and Tasin cl 1-1 280 (YC99551) to the south and east. At the conclusion of staking the property covered 1 692 claims that extended onto topographic map sheets 106C 01 to the east and 105N 15 & 16 to the south. In Sep/2011 the company flew a LIDAR survey over the northern part of the property.
 
In 2012 Strategic Metals carried out further geological mapping, rock sampling and grid based soil sampling. The company also collared 15 diamond drill holes (2 924.56 m) on the property, of which 6 holes (804.98 m) tested the Malbec zone, 1 hole (169.16 m) tested the Shiraz zone, one hole (185.93 m) tested soil Anomaly A and 1 hole (203.3 m) tested soil Anomaly B.

GEOLOGY
 
The Crag East property lies approximately 165 km east-northeast of Mayo and approximately 10 km northeast of Ortell Lake in east-central Yukon. Access to the property in 2011 and 2012 involved a fixed-wing aircraft to a landing strip at ATAC Resources’ Rackla airstrip, located approximately 36 km to the northwest and then employing a helicopter to the property.
 
The area was geologically mapped in the early 1970’s by S Blusson of the Geological Survey of Canada (1974 – 1:250 000 scale) as part of Operation Stewart. Blusson’s maps were used by most geologists and exploration companies until 2010 when the Yukon Geological Survey initiated a project to better understand the geology of the area following the discovery of Carlin-type gold mineralization on ATAC Resources’ Rackla Gold Project located to the north. M. Colpron et al. of the Yukon Geological Survey geologically mapped topographic map sheet 106C 02 (Ortell Lake– 1:50 000 scale) in the summer of 2012 and a geological map was released in 2013.
 
The occurrence area is located on the northern margin of the Selwyn basin and on the hanging wall side of the Dawson thrust, a crustal break which thrusts regionally metamorphosed basinal sediments north onto carbonate platform rocks assigned to the Mackenzie platform. The occurrence area is located within a northwesterly trending, fault-repeated sequence of Neoproterozoic (Ediacaran) to Lower Cambrian, Hyland Group, Yusezyu, Algae Lake and Narchilla formations. Based on geological mapping by Colpron and geologists employed by Strategic Metals, the Malbec zone (occurrence location) is located within a fault bounded block of Algae Lake Formation limestone and dolomite.
 
Soil sampling carried out in 2011 & 12 outlined a northwest trending anomaly measuring approximately 4 000 m long by 100 to 650 m wide which Strategic Metals named the Malbec anomaly. The Malbec anomaly contains gold values ranging from 10 to 2 410 ppb and very strong pathfinder elements including arsenic (200 to 2 900 ppm), mercury (10 to 28 ppm), antimony (10 to 447 ppm) and thallium (10 to 56.7 ppm). These values are similar to those observed at sites hosting Carlin-style gold mineralization located at ATAC Resources’ Rackla Gold project located to the north. In addition the company outlined several secondary anomalies that parallel both sides of the main anomaly. The 2011 LIDAR survey was flown in order to obtain an enhanced view of the regions topography.
 
In 2012 Strategic Metals collected 48 deep soil samples from within the northeastern half of the Malbec zone. The samples were collected to compare the results of samples collected from shallow depths (~ 50 cm) to those obtained from samples collected from a deeper depth (~ 137 cm). Results show that the average values for arsenic, gold mercury, antimony and thallium are relatively comparable.
 
Prospecting and geological mapping defined the Malbec zone within the soil anomaly. The zone lies in a heavily vegetated area containing less than 1 % rock exposure. Prospecting in 2011 uncovered a mineralized cobble which returned 0.70 % arsenic, 1 270 ppm mercury, 6.05 ppm thallium and 29.1 ppm antimony. A trench dug in 2012 over the site of the cobble cut a soliflucted package of shattered bedrock comprised of blue grey clay containing minor realgar fragments, very weakly calcareous dolostone, strongly clay-altered very porous decalcified dolostone containing moderate, pervasive realgar and shattered green-orange weathering shale. A second trench dug 400 m to the northwest of the first trench exposed poorly consolidated breccia containing angular, tan to gray dolostone fragments within a porous, black-orange matrix.
 
Prospecting carried out in 2011 led to the discovery of the Shiraz zone (UTM 7107970 N, 619135 E) located approximately 1.9 km north-northwest of the Malbec zone. The zone lies at the contact between Yusezyu Formation siliciclastic rocks to the south and an unnamed fossiliferous limestone to the north. This contact likely represents the surface trace of the Dawson thrust. The zone overlies a prominent arsenic rich gossanous seep. A sample of dark red to black, limonite collected from within the area of the seep returned 1.1 % arsenic and 2.13 % zinc but low values for gold and other Carlin-type pathfinder elements. Two diamond drill hole collared in 2011 below the gossan intersected strong clay alteration, silicification and elevated pathfinder elements.
 
The 2012 diamond drill program tested the Malbec and Shiraz zones and two soil anomalies (Anomaly A and B).  Drilling intersected favorable silty limestone, debris flows, styolites and breccias units which hosted strong clay alteration and decarbonisation common to Carlin-style gold deposits. Although no economic intersections of gold mineralization were encountered, the holes intersected thick intervals containing intense pathfinder signatures, including 1.03 % arsenic, 86.1 ppm mercury and 50.6 ppm thallium across 60.8 m. Strategic Metals stated that the results are consistent with classic Carlin-style zoning where pathfinder geochemical signatures are typically found above and adjacent to gold zones. Many geochemical anomalies on the property have not yet been followed up, including many low-level gold anomalies which have proven to be important elsewhere in Rackla Gold district. 
 

Location Map

Last Updated: Feb 10, 2017

Work History

Year Work Type Comment
2012 Drilling: Diamond Fifteen holes (2,924.56 m) total. Nine holes tested Malbec, Shiraz and two soil anomalies.
2012 Geochemistry: Rock Sampled various showings.
2012 Geochemistry: Soil Follow-up sampling. Also deep sampling over part of Malbec zone.
2012 Geology: Detailed Bedrock Mapping Follow-up mapping of mineralized zones.
2011 Airphotography LIDAR survey flown over northern portion of claim block.
2011 Drilling: Diamond Six holes (1,398.73 m) total. Two holes (384.05 m) collared on Shiraz zone.
2011 Geochemistry: Silt Property wide.
2011 Geochemistry: Soil Reconnaissance scale followed by grid based.
2011 Geology: Detailed Bedrock Mapping Around mineralized zones.
2011 Other: Prospecting Property wide.

Regional Geology - Terrane

Group: Ancestral North America
Affinity: W Laurentia
Name: North America - basinal strata
Realm: Laurentia


Regional Geology - Bedrock

Supergroup: Windermere
Group/Suite: upper
Formation: Blueflower
Member: undivided
Terrane: Laurentia
Period Max: Ediacaran
Age Max: 635 MA
Period Min: Cambrian
Age Min: 542 MA
Rock Major: variably calcareous mudstone, sandstone, grit, quartzite, conglomerate, limestone
Rock Minor:
Reference: Moynihan (2016) - YGS OF 2016-2
Geological Unit (1M): uPB
Geological Unit (250K): uPB

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
096596 2012 Assessment Report Describing Geochemical Sampling, Prospecting, Geological Mapping, Hand Trenching and Diamond Drilling at the Crag East Property Diamond - Drilling, Rock - Geochemistry, Detailed Bedrock Mapping - Geology, Prospecting - Other, Hand - Trenching 15 2924.56
095921 2011 Assessment Report Describing Geochemical Sampling, Geological Mapping and Diamond Drilling at the Midas Touch Project Crag East Property Diamond - Drilling, Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Prospecting - Other, LIDAR - Remote Sensing 6 1398.73
095712 2010 Assessment Report Describing Geochemical Sampling, Geological Mapping, Diamond Drilling and Geophysical Surveys at the Nadaleen Trend Property ZTEM - Airborne Geophysics, Diamond - Drilling, Drill Core - Geochemistry, Rock - Geochemistry, Soil - Geochemistry, Detailed Bedrock Mapping - Geology, Regional Bedrock Mapping - Geology, Prospecting - Other 9 1898.28

Related References

Number Title Page(s) Document Type
YEG2011_OV Yukon Exploration and Geology Overview 2011 p. 26. Annual Report
YEG2012_OV Yukon Exploration and Geology Overview 2012 p. 35-36, 65. Annual Report
2013-13 Geological map of the Rackla belt, east-central Yukon (NTS 106C/1-4, 106D/1) Sheet 2, Ortell Lake. Open File (Geological - Bedrock)
Citations
STRATEGIC METALS LTD. Apr/2012. Assessment Report #095921 by K. Unger.
STRATEGIC METALS LTD. Aug/2013. Assessment Report #096596 by S. Drechsler.
STRATEGIC METALS LTD. Feb/2017. Web Site: www.strategicmetalsltd.com.
STRATEGIC METALS LTD. News Release. 14 Sep/2011, 20 Dec/2011, 31 May/2012, 5 Sep/2012, 20 Jun/2013.

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