The Stranby occurrence is located on a north-facing slope, west of Shuttleworth Bight and approximately 900 metres west-northwest of the mouth of the Stranby River. Note: Assessment Report 2383 erroneously locates the occurrence east of the mouth of Stranby Creek.
Regionally, the area is underlain by a northwest-trending series of sedimentary and volcanic rocks comprising basaltic volcanic rocks of the Upper Triassic Karmutsen Formation (Vancouver Group), which is overlain by limestone of the Upper Triassic Quatsino Formation (Vancouver Group) and limestone, mudstone and siltstone of the Upper Triassic Parson Bay Formation (Bonanza Group) that have been intruded by quartz diorite to granodiorite of the Lower to Middle Jurassic Island Plutonic Suite.
Locally, a 10-metre-thick limestone band within basalts has been altered to garnet-epidote-calcite-quartz skarn, containing chalcopyrite with minor bornite and magnetite. A granodiorite stock occurs east of Stranby River and country rocks in this vicinity are strongly fractured. Within the basalts and stratigraphically 100 metres below the limestone-skarn zone lies a layer of massive magnetite, ranging in thickness from 5 to 60 centimetres. Significant amounts of chalcopyrite are reported locally within the magnetite (Assessment Report 1847, page 19).
Mineralization has been intermittently traced along surface by trenches for several hundred metres to the south-southeast. A northeast-trending strike-slip fault with left-lateral displacement offsets the mineralized zones by 30 metres. The occurrence is similar and on strike with Ed Creek (MINFILE 102I 003) occurrence.
Work History
During 1968 through 1970, Quintana Minerals Corp. completed a program of geological mapping, geochemical (rock, silt and soil) sampling, trenching and a 31.0 line-kilometre induced polarization survey on the area as the Cape Scott (CS) claims. Two samples of vein material from a shoreline outcrop yielded 0.73 and 1.34 per cent copper over 3 metres, respectively (Assessment Report 1847).
In 1982, Electra North West Resources Ltd. completed a program of soil sampling and a ground magnetometer survey on the area as the BU, DU and SU claims. In 1984, a further ground magnetic survey was completed.
In 1990, Westword Explorations staked the area as the Shuttle 1-4 claims of the Shuttleworth Property and completed a program of prospecting, geochemical (rock and silt) sampling and 10.0 line-kilometres of ground magnetic and electromagnetic surveys. This work identified a number of VLF-EM anomalies and a north-northwesterly magnetic high. Two grab samples (57812 and 57813) from a historical trench, located several hundred metres south-southeast of the shoreline outcrop, yielded 3.993 and 2.617 per cent copper, 0.321 and 2.366 per cent zinc, 600.8 and 11.9 grams per tonne silver with 0.570 and 1.560 grams per tonne gold, respectively (Assessment Report 21369).
During 1991 through 1996, Winfield Resources completed programs of prospecting, geological mapping, geochemical (rock, soil and heavy mineral) sampling and ground magnetic and electromagnetic surveys on the area as the Duck 1-14 and Shuttle 1-6 claims of the Shuttleworth property. This work identified an erratic band of soil gold anomalies over 650 metres in length centred on a magnetic low between two elongate magnetic highs west of the Stranby River.
