General Information
Secondary Commodities: antimony, arsenic, bismuth, gold
Deposit Type(s): Plutonic Related Au
Location(s): 64.388060 N, -137.615280 W
NTS Mapsheet(s): 116A05
Location Comments: .5 Kilometres
Hand Samples Available at YGS: No
Capsule
Work History
The occurrence was originally staked as Heidi cl 1-24 (YB64644) in Aug/95 by Homestake Canada Inc. In Oct/95 the company added Heidi cl 25-101 (YB65121). Homestake carried out a preliminary exploration program in the fall of 1995 and further prospecting, geological mapping and soil sampling in the summer of 1996. In 1998 the company carried out additional geological and geochemical prospecting.
Mar-West Resources Ltd staked Ho cl 1-56 (YB64949) east of the Heidi claims in Sept/95. In Nov/95 the company staked Clare cl 1-65 (YB67641) east of the Ho claims. Both claim groups were refused by the Mining Recorder for the Mayo Mining District.
In Apr & May/96, D. Jacob, R. Quesnel and A. Richer staked Hi cl 17-39 (YB81576) and Hi cl 49-111 (YB81599) for Pacific Galleon Mining Corporation immediately to the south of the Heidi claims. Pacific carried out prospecting, silt and soil sampling in Jun & Jul/96.
Capsule Geology
The occurrence is located within the eastern Selwyn Basin and is underlain by Upper Proterozoic to Early Cambrian Hyland Group rocks. Two distinct formations are recognized in the area: the Yusezyu Formation and the Narchilla Formation. The Yusezyu Formation consists of rusty weathering gritty quartzite, sandstone and quartz pebble conglomerate with up to 80 or 90 % rounded quartz grains. Minor interbeds of limestone, calcareous sandstone and shale are common. The Narchilla Formation consists of black, maroon and green shales and slates. This unit is quite distinct and is usually identifiable from a distance. Regionally, mid-Cretaceous Selwyn Suite syenite stocks intrude the Hyland Group rocks.
The Heidi showing consists of 5 - 50 % massive to disseminated arsenopyrite, pyrite and stibnite/jamesonite replacing limestone and calcareous grit units. Irregular, narrow quartz/arsenopyrite veins intersect the mineralized beds and probably channelled the mineralizing fluids into the favourable horizons. The mineralization is quite poddy but is mainly localized within the recumbently folded south limb of the Heidi anticline, near the Yusezyu/Narchilla contact. The mineralization is contained within an area measuring approximately 300m long and 100 m high.
Homestake completed 5 blast trenches (28.5 linear metres) in the fall of 1995 before bad weather forced them to quit for the season. A 1 m chip sample (trench 95-3) collected from extremely rusty and limonite stained siltstone with interbedded grit and containing 1% arsenopyrite and 5% pyrite returned 2.06 g/t Au, 1.4% As, 3 985 ppm Sb and 0.2% Bi. A second 1 m chip sample (trench 95-5) collected from a rusty weathering green serecite and scorodite rich grit returned 2.93 g/t Au, 713 ppm As and 175 ppm Sb.
Geological mapping completed in1996 uncovered several coarse-grained biotite-feldspar porphyry dykes on the Heidi ridge and near Heidi Lake. Their presence hints that a larger granitic stock may exist at depth beneath the claims. This theory is reinforced by a magnetic anomaly centred over Heidi Lake. Extensive hornfelsing typically associated with Cretaceous granitic stocks was not observed on the Heidi claims, implying that a buried stock would be at least 100m below surface.
Soil sampling outlined two strong Au/As/Sb geochemical anomalies along the ridge extending west from the occurrence. The samples returned values up to 1 150 ppb Au and coincide with heavily mineralized float. Soil sampling on the north slope of Heidi ridge identified 3 moderate to strong anomalies which returned values up to 940 ppb Au and 1 880 ppb As.
Work on the Hi claims to the south by Pacific Galleon during 1996 included prospecting, silt and soil sampling along the south facing cliffs and slopes. The best soil sample returned 17 ppb Au.
The 1998 Homestake field program concentrated on the area east of the known mineralization. Prospecting uncovered an outcrop of feldspar-biotite porphyry but no mineralization. A line of soil samples returned elevated levels of As but only background levels of Au.
References
HOMESTAKE CANADA INC, Oct/96. Assessment Report #093536 by R.A. Doherty.
HOMESTAKE CANADA INC, Dec/96. Assessment Reports #093524 and #093518 by D. Bordin, A. Ross and D. Kuran.
HOMESTAKE CANADA INC, Dec/98. Assessment Report #093920 by M. Papageorge.
PACIFIC GALLEON MINING CORP, May/97. Assessment Report #093691 by S. Gower.
The occurrence was originally staked as Heidi cl 1-24 (YB64644) in Aug/95 by Homestake Canada Inc. In Oct/95 the company added Heidi cl 25-101 (YB65121). Homestake carried out a preliminary exploration program in the fall of 1995 and further prospecting, geological mapping and soil sampling in the summer of 1996. In 1998 the company carried out additional geological and geochemical prospecting.
Mar-West Resources Ltd staked Ho cl 1-56 (YB64949) east of the Heidi claims in Sept/95. In Nov/95 the company staked Clare cl 1-65 (YB67641) east of the Ho claims. Both claim groups were refused by the Mining Recorder for the Mayo Mining District.
In Apr & May/96, D. Jacob, R. Quesnel and A. Richer staked Hi cl 17-39 (YB81576) and Hi cl 49-111 (YB81599) for Pacific Galleon Mining Corporation immediately to the south of the Heidi claims. Pacific carried out prospecting, silt and soil sampling in Jun & Jul/96.
Capsule Geology
The occurrence is located within the eastern Selwyn Basin and is underlain by Upper Proterozoic to Early Cambrian Hyland Group rocks. Two distinct formations are recognized in the area: the Yusezyu Formation and the Narchilla Formation. The Yusezyu Formation consists of rusty weathering gritty quartzite, sandstone and quartz pebble conglomerate with up to 80 or 90 % rounded quartz grains. Minor interbeds of limestone, calcareous sandstone and shale are common. The Narchilla Formation consists of black, maroon and green shales and slates. This unit is quite distinct and is usually identifiable from a distance. Regionally, mid-Cretaceous Selwyn Suite syenite stocks intrude the Hyland Group rocks.
The Heidi showing consists of 5 - 50 % massive to disseminated arsenopyrite, pyrite and stibnite/jamesonite replacing limestone and calcareous grit units. Irregular, narrow quartz/arsenopyrite veins intersect the mineralized beds and probably channelled the mineralizing fluids into the favourable horizons. The mineralization is quite poddy but is mainly localized within the recumbently folded south limb of the Heidi anticline, near the Yusezyu/Narchilla contact. The mineralization is contained within an area measuring approximately 300m long and 100 m high.
Homestake completed 5 blast trenches (28.5 linear metres) in the fall of 1995 before bad weather forced them to quit for the season. A 1 m chip sample (trench 95-3) collected from extremely rusty and limonite stained siltstone with interbedded grit and containing 1% arsenopyrite and 5% pyrite returned 2.06 g/t Au, 1.4% As, 3 985 ppm Sb and 0.2% Bi. A second 1 m chip sample (trench 95-5) collected from a rusty weathering green serecite and scorodite rich grit returned 2.93 g/t Au, 713 ppm As and 175 ppm Sb.
Geological mapping completed in1996 uncovered several coarse-grained biotite-feldspar porphyry dykes on the Heidi ridge and near Heidi Lake. Their presence hints that a larger granitic stock may exist at depth beneath the claims. This theory is reinforced by a magnetic anomaly centred over Heidi Lake. Extensive hornfelsing typically associated with Cretaceous granitic stocks was not observed on the Heidi claims, implying that a buried stock would be at least 100m below surface.
Soil sampling outlined two strong Au/As/Sb geochemical anomalies along the ridge extending west from the occurrence. The samples returned values up to 1 150 ppb Au and coincide with heavily mineralized float. Soil sampling on the north slope of Heidi ridge identified 3 moderate to strong anomalies which returned values up to 940 ppb Au and 1 880 ppb As.
Work on the Hi claims to the south by Pacific Galleon during 1996 included prospecting, silt and soil sampling along the south facing cliffs and slopes. The best soil sample returned 17 ppb Au.
The 1998 Homestake field program concentrated on the area east of the known mineralization. Prospecting uncovered an outcrop of feldspar-biotite porphyry but no mineralization. A line of soil samples returned elevated levels of As but only background levels of Au.
References
HOMESTAKE CANADA INC, Oct/96. Assessment Report #093536 by R.A. Doherty.
HOMESTAKE CANADA INC, Dec/96. Assessment Reports #093524 and #093518 by D. Bordin, A. Ross and D. Kuran.
HOMESTAKE CANADA INC, Dec/98. Assessment Report #093920 by M. Papageorge.
PACIFIC GALLEON MINING CORP, May/97. Assessment Report #093691 by S. Gower.
Location Map
Last Updated: Sep 15, 2011
Work History
| Year | Work Type | Comment |
|---|---|---|
| 1998 | Geochemistry: Soil | Work confined to area east of occurrence. |
| 1996 | Geochemistry: Soil | |
| 1996 | Geology: Bedrock Mapping | |
| 1995 | Trenching | Five trenches (28.5 linear m) were blasted. |
Regional Geology - Terrane
Group: Ancestral North America
Affinity: W Laurentia
Name: North America - basinal strata
Realm: Laurentia
Regional Geology - Bedrock
Supergroup: Windermere
Group/Suite: Hyland
Formation: Yusezyu
Member:
Terrane: Laurentia
Period Max: Ediacaran
Age Max: 635 MA
Period Min: Ediacaran
Age Min: 542 MA
Rock Major: phyllite/shale/sandstone/grit/conglomerate/limestone
Rock Minor: marble
Reference: Green & Roddick (1972) - GSC Map 1283A
Geological Unit (1M): PCH
Geological Unit (250K): PCH6
Assessment Reports that overlap occurrence
| Report Number | Year | Title | Worktypes | Holes Drilled | Meters Drilled |
|---|---|---|---|---|---|
| 095275 | 2008 | 2008 MMI Soil Geochemical Report on the Heidi Property | Soil - Geochemistry | ||
| 094866 | 2007 | Helicopter Magnetic and Radiometric Survey for Logan Resources Ltd. on the Heidi Claims Project | Gamma-Ray Spectrometry - Airborne Geophysics, Magnetic - Airborne Geophysics | ||
| 095593 | 2006 | Report on Interpretation of Induced Polarization, Magnetic and Horizontal Loop Electromagnetic Geophysical Surveys (To Define Drill Targets) on the Heidi Property | EM - Ground Geophysics, IP - Ground Geophysics, Magnetics - Ground Geophysics | ||
| 094542 | 2004 | 2004 Geological & Geochemical Report on the Heidi Property | Rock - Geochemistry, Prospecting - Other, Data Compilation - Pre-existing Data | ||
| 093524 | 1996 | Assessment Report 1996 Geological and Geochemical Program Heidi Property | Rock - Geochemistry, Soil - Geochemistry, Detailed Bedrock Mapping - Geology | ||
| 093518 | 1996 | Assessment Report 1996 Geological and Geochemical Program Heidi Property | Rock - Geochemistry, Soil - Geochemistry, Detailed Bedrock Mapping - Geology | ||
| 093536 | 1995 | Report on the 1995 Trenching Program on the Heidi Claims | Rock - Geochemistry, Handblast - Trenching |
