Ponderosa Gold Property
OVERVIEW
Highlights | |
Location: | 16km from Merritt BC, in the heart of the Spence’s Bridge Gold Belt (3 hours drive from Vancouver BC) |
Ownership: | Central claim (100%), earning into 100% of surrounding claims |
Status: | Drilling – Pre-discovery |
Geology: | Low sulphidation epithermal gold-silver mineralization |
Au Gold Corp has been following up on the initial prospecting discovery made by Ed Balon of Almaden Minerals in the early 2000’s. Anomalous gold values led to the discovery of Axel Ridge, where outcrop and abundant quartz float material returned multi-gram gold values with epithermal textures.
The Company has continued exploration by carrying out soil sampling, prospecting, trenching and drilling, resulting in a new and untested interpretation of the mineralization at Ponderosa.
The Company plans to drill test the Ponderosa Structural Corridor to locate the source of the gold bearing mineralization at Axel Ridge and elsewhere on the property.
Project Highlights
- Prospecting samples grading up to 46.9 g/t gold and 110 g/t silver
- Excellent road access to and through the property
- Short winter – long exploration season with low rainfall
- Great potential for a drill discovery
Location
The property is located 16 km southwest of Merritt, BC, less than three hours drive from Vancouver, Canada. Access by road is via the sealed Coldwater Road from either Merritt or the Coquihalla Highway (Exit 256) and then 9km by way of paved and gravel roads from the Coldwater/Patchett Road junction. The property is located within the unceded traditional territory of the Nlaka’pamux People.
History
2002 | Reconnaissance geochemical sampling and prospecting in the region by Ed Balon for Almaden Minerals, following up on government stream sediment sample results |
2005 | Follow up of geochemical anomalies generated during 2002, including the first soil samples taken at Ponderosa |
2006 | Axel Ridge prospect discovered, additional soil sampling completed |
2007 | Project optioned to Strongbow Exploration Inc., first drilling at Ponderosa, focused on Axel Ridge |
2018 | Additional claims staked by Ed Balon (retired) |
2019 | Claims optioned by Ponderosa Exploration (now owned by Au Gold Corp), prospecting carried out, additional zones of mineralization sampled |
2020 | Additional soil sampling completed, prospecting, Au Gold Corp acquires Ponderosa Exploration, |
2021 | Prospecting, sampling and trenching carried out at Tomahawk Zone |
2022 | Diamond drilling at Tomahawk Zone |
2023 | Development of the Ponderosa Structural Corridor interpretation to guide future exploration |
Geology
The project area lies within the Spences Bridge Gold Belt which forms a northwest trending belt roughly 180 km long and up to 24 km wide. Rocks of immediate interest in the belt and underlying much of the project area comprise successions of Cretaceous subaerial and pyroclastic volcanic flows which host significant gold mineralization at Westhaven Gold’s Shovelnose prospect approximately 20 km southeast of Ponderosa. Exploration at Shovelnose is somewhat hindered by relatively extensive overburden cover which in places exceeds 100 m thickness. Mineralization is contained in steeply dipping northwest trending vein zones cumulatively traced for 700 m along strike over vertical ranges up to 300 m. Significant gold mineralization is well constrained within a 140 m vertical range locally between 1138 and 1278 m elevation. Shovelnose core intersections exhibit classic crustiform-colloform-banded quartz-adularia ginguro textures. In places visible gold is observed and numerous significant intercepts have been reported including:
- 46.20 m grading 8.95 g/t Au, 65.47 g/t Ag
- 17.77 m grading 24.5 g/t Au, 107.9 g/t Ag
The Ponderosa property comprises 420 ha occupying several localized ridges and knolls, part of a more extensive northerly trending ridge system. Elevations across the project area range from 1,270 to 980 m. Glacial till and overburden cover is highly variable forming thin veneers to metres thick blankets at lower elevation. Outcrop exposure is sporadic, but relatively abundant at higher elevation. Geology across the claim block is broadly divided into two Cretaceous age volcanic sequences comprising subaerial and pyroclastic volcanic flows of the Pimainus and Spius Formations. Mapping by previous operators with experience in the Spences Bridge Gold Belt observed this stratigraphy as the host of the Westhaven mineralization. Of particular interest are the lower formation Pimainus volcanics which constitute the majority of the Ponderosa project area. Pimainus stratigraphy at Ponderosa is described as greenish grey to bluish grey, dense, andesitic flows. Commonly porphyritic with up to 30%, 2-5 mm, subhedral to euhedral feldspar and 10% combined hornblende/pyroxene phenocryst. These rocks are shown to be unconformably overlain by brown to brownish grey, green and reddish grey to maroon Spius Formation andesitic flow and flow breccias with up to 30% elongate calcite filled amygdules. Very little property scale structural mapping has been conducted at Ponderosa. Of note however, are a series of inferred northeasterly- trending sinistral normal faults believed to have associated lateral displacement in the range of metres to kilometres. Vertical components of displacement are unknown. Fracture sets noted in volcanics elsewhere on the property include a variety of orientations including conjugate sets and oblique subsets to the northeasterly trend.
Exploration over the ground currently defining the Ponderosa property has largely been limited to soil geochemistry and prospecting. Small localized targets identified from this work were infill sampled at closer spacing for enhanced definition. This work identified a number of showings across the property, the most highly regarded of which at the time was an in-situ occurrence referred to as Axel Ridge. The majority of the subsequent exploration programs focused on the Axel Ridge area conducting manual and mechanized trenching, ground magnetic geophysical surveys and six to eight diamond drill holes. Six holes are documented in assessment reports and two holes are said to have been drilled as follow-up by another operator (personal communication) but the locations and results are not confirmed. Soil geochemical anomalism was examined closely specifically for gold-in-soil results in order to identify specific trends. The tenor of the soil responses is generally low with the exception of the Axel Ridge area where in-situ vein mineralization is locally abundant on surface. At this location soil samples returned in excess of 100’s of ppb Au at select sites. However, utilizing a roughly 80th percentile cut-off and doubling the intervals between specific threshold ranges (5-10 ppb, 10-20 ppb, 20-40 ppb, >40 ppb), successfully identified repeatable linear trends within three well constrained specific orientations. These orientations are estimated as follows: 330-335, 010-017 and 030-038 degrees. Other accessory elements arsenic, silver, antimony and mercury were reviewed but gold in soil geochemistry provides the best base defining potential source related trends likely associated with an underlying hydrothermal structural system. Glacial till cover likely masks gold response in some areas of the property.
Property wide prospecting has identified a number of gold bearing float specimens, the bulk of which are located in the lower elevation southern portion of the claims. The majority of the samples comprise crustiform to crypto-crystalline to saccharoidal quartz of varying sizes up to 10’s of cm on a side. Most samples collected were of angular nature suggesting a relatively local source. The highest gold values were obtained from a piece of crypto-crystalline to saccharoidal quartz in excess of 20 cm on a side which returned 46.90 g/t gold and 110 g/t silver. A subset of all the prospect sampling from the property was taken for those samples returning > 1g/t Au and reviewed for Ag:Au ratio values and consistency. It was found that ratios are fairly well constrained in a range between 1:1 and 6:1 with an average of 3:1 Ag:Au.
Zones
The property features a number of zones or showings where geological evidence has been located.
Management believes the Ponderosa Structural Corridor is the most prospective part of the property and plans to focus its efforts on drill testing this corridor which exceeds 2km in length. The Ponderosa Structural Corridor has been interpreted from a range of data sources, including soil sampling, prospecting, mapping and geophysics.
In 2022, the Company completed a drill program on the Tomahawk and Flat Iron zones based on the presence of gold bearing, steeply dipping epithermal quartz veins that outcropped at surface with widths up to 25m. Management now believes that the Tomahawk and Flat Iron zones are parallel trend structures and of lesser significance than the zones in the Ponderosa Structural Corridor.
Axel Ridge
Historical exploration at Ponderosa began with broadly spaced soil geochemistry and prospecting which led to the identification of a number of showings across the property. Prior operators focused almost exclusively on an in-situ occurrence referred to as “Axel Ridge”, which is characterized by outcropping cryptocrystalline/saccharoidal to crustiform and colloform banded epithermal quartz. A series of trenches were excavated across these outcropping exposures with highlights including 2.22 g/t gold over 11.7 m, 1.92 g/t gold over 14.0 m (with 3.03 g/t gold over 8.0 m) and 3.6 g/t gold over 7 m. Follow-up diamond drilling of seven holes at Axel Ridge was unsuccessful in intersecting the surface mineralization at depth. A localized ground magnetic geophysical survey was also carried out by prior operators.
Axel Ridge is situated at the center of the Ponderosa Structural Corridor and is an enigmatic occurrence that was drill tested by previous operators. Despite multi-gram gold samples up to 12.82 g/t gold at surface and favourable epithermal textures, drilling was unable to trace the zone even to shallow depths. In conjunction with the Ponderosa Structural Corridor, management now interprets Axel Ridge to be associated with lateral fluid flow along the paleo gradient, rather than an upflow or feeder zone. Management believes feeder zones are located close by and likely at lower elevations along the Ponderosa Structural Corridor. Future drilling at Ponderosa will focus on identifying the source of these gold-bearing fluids and following them to depth.
T-Bone
The T-Bone Zone hosts the strongest and most continuous gold-arsenic geochemistry on the property but has only received cursory surface exploration to date in the form of minor historical hand pits as much of the area is overburden/till covered. Follow-up prospecting of elevated soil sample sites along the main access road through the central part of the T-Bone target area identified a 3 m wide zone of bleached and clay altered silicified volcanic subcrop. A composite sample of select material across the zone yielded 0.47 g/t gold. This zone is believed to be one of a number of high-level mineralized structures defining the T-Bone gold-arsenic soil geochemical anomaly and remains to be drill tested.
Cattle Guard
Insert description
Ribeye
The Ribeye Zone was first identified during the 2019 soil sampling program, which located a narrow excavation that exposed a zone of extremely hydrothermally altered volcanic strata completely converted to orange, white and tan clay with intermittent clear and white silica veinlets. The excavation is parallel to the alteration zone therefore only a narrow section of the silicified footwall volcanic is exposed and the clay alteration is also only partially exposed across a width of 3.70 m. Samples of the clay material collected from the trench were analyzed and identified as low temperature smectite group clays comprising montmorillonite and laumontite. The orientation of the Ribeye alteration trends southwest toward the strongest gold-in-soil value (110 ppb) in the area and dips are steep northwest. Also of note in this area is the highest gold value obtained from prospecting samples on the property, reported to have returned 46.9 g/t gold and 110 g/t silver. Although sampling across the trench exposure returned low values for gold, the Ribeye Zone is deemed significant as it is may represent a high level telescoping portion of a fertile hydrothermal system at depth.
Tomahawk
The Tomahawk Zone was identified through historical prospecting as a quartz rubble pile roughly 3 m in diameter. Six surface samples collected by a prior operator from the quartz rubble area returned grades from below detection to 0.54 g/t gold but the lack of soil geochemical response over this target and apparent lack of strike extent of the surface exposure discouraged any follow-up exploration. The site was investigated further in 2019 and additional in-situ mineralization was located 50 m to the southwest, believed to be associated with the initial discovery. Six samples of weakly crustiform to cryptocrystalline/saccharoidal quartz returned values ranging from below detection limits to 2.96 g/t gold. Five hand trenches were located at varying intervals across the two exposures to identify the nature, width and orientations of the respective vein zones. All trenches reached bedrock, encountering significant widths of silicification, brecciation and clay altered volcanic clasts, quartz flood zones resembling sheeted veinlets and veins, and massive quartz vein material.
Visually, Tomahawk presented a compelling target with veining and silicified volcanics (stockwork) identified across up to 25 m widths and the interpreted dip of 55 – 75 degrees made this a high priority drill target for the Company.
In 2022, sixteen drillholes were located along a 200 m section of the Tomahawk Zone from the trench exposures in the south and northward along the trend defined by weak gold and arsenic-in soil geochemistry and a subtle elevated linear ridge apparent from the digital terrain data. The moderately westward dipping Tomahawk structural zone is characterized by a complex series of late destructive silica-rich floods and breccia events overprinting earlier classic banded epithermal veins and vein zones. This extensive silicification and brecciation appears to be non-gold bearing.
Epithermal vein clasts commonly occur as breccia fragments and range from angular to sub-rounded indicating multi-stage overprint emplacement with varying degrees of fragment milling. Matrix supported breccias are white to dark grey, the latter containing abundant fine to- ultrafine grained pyritization as clusters and concentrations along fragment boundaries resembling epithermal style banding. Later-stage alteration overprint includes grey silica-hematite as crackle and mosaic breccias, veins, veinlets and stringers. All mineralization contains latest-stage carbonate alteration.
Narrow epithermal veins and portions of vein zones preserved within the late destructive silica structural overprint are dominantly quartz-adularia and exhibit classic coliform, comb and cockade textures with lesser ginguro banding and occasional amethyst. Intervals grading in excess of 1 g/t gold are mostly associated with preserved epithermal vein mineralization in the broader silica alteration zone. The footwall of the Tomahawk structural zone hosts the highest concentration of narrow unaltered epithermal veins and veinlets. The best example is observed from PD22-13 where a 1.0 m interval of mildly silicified footwall volcanic host contains approximately 15% epithermal veining and graded 2.20 g/t gold.
Cross Sections:
https://augoldcorp.com/wp-content/uploads/2022/08/Drill-Highlights1.pdf
Flat Iron
The Flat Iron Zone is situated approximately 100 m south of the Tomahawk Zone and is interpreted as a sinistral structural offset of the Tomahawk Zone by an easterly trending property-scale structure. The Flat Iron Zone is defined by two historical trenches comprising roughly 85 m of mechanized trenching which identified a number of significant quartz zones, zones of brecciation, silicification and pyritization. Individual samples from the longer of the two trenches (~65 m) reportedly assayed up to 7.54 g/t gold while a weighted average across 25 m yielded 0.80 g/t gold. The main zone of quartz veining observed is described as white to grey, opaque, cryptocrystalline material with <1mm black bands. This zone was mapped as being bound to the east by a steeply dipping vertical fault zone containing abundant quartz fragments within pervasively argillic and chlorite altered fault gouge with oxidized and weathered pyrite.
During 2022, four drill holes located at the Flat Iron Zone tested silicified bedrock exposures along strike from the historical gold-bearing trenches. Broad zones of silicification, brecciation and manganiferous-hematization were encountered as interpreted from the surface exposures but these zones appear to be similar in nature to the late-stage non-gold-bearing structural alteration observed at the Tomahawk Zone. Only rare high-level epithermal veins/veinlets were encountered, unlike the concentrations of epithermal vein mineralization at surface and lower elevations to the north. No anomalous gold intervals were sampled from the Flatiron drill holes.
Cross Sections:
Exploration Plan
The 2022 drill program at Ponderosa was technically successful in definitively intersecting epithermal gold mineralization (18.91m @ 0.44 g/t gold). Drilling was unable to intersect the gold bearing mineralization at depth below Tomahawk due to a range of factors, including topography and structural complexity. Potential exists to the south and west of current drilling for gold bearing mineralization.
Dr. Jeffrey Hedenquist was invited to visit the property after the 2022 drill program and he prepared a report on his findings:
Expert Report – Dr. Jeffrey Hedenquist
As a result of the information in this report, management now believes the highest priority exploration target is to locate the source of the ore bearing fluids at Axel Ridge. One possible explanation for this zone, which features multi-gram gold values is that it represents lateral flow along the paleo gradient. Finding the location at which these ore bearing fluids sourced from is therefore an important target.
Concurrently, management has completed infill soil sampling and combined this information with mapping, drone photogrammetry and geophysics to create an interpretation of the Ponderosa Structural Corridor:
Management proposes to test the Ponderosa Structural Corridor, both north and south of Axel Ridge to try to locate zones of upwelling ore bearing fluids. Initially, shallow RAB (Rotary Air Blast) drilling will be used to locate zones of quartz veining that can be followed to depth by diamond drilling.