The Sha occurrence is centred on diamond-drill hole S87-1, located approximately 15 kilometres southeast of Creston (Assessment Report 16769).
Regionally, the area is underlain by the peri-cratonic Middle Proterozoic Purcell Supergroup, a thick succession of siliciclastic and lesser carbonate rocks. The Purcell Supergroup is well known for hosting a number of significant deposits that include the Sullivan (082FNE052) sedimentary-exhalative lead-zinc deposit and the Troy copper-silver deposit in Montana.
More locally, the area of interest is underlain by the Aldridge Formation. The Aldridge Formation is the lowermost division of the Purcell Supergroup and is composed of turbiditic siliciclastic rocks and numerous gabbro sills. The focus of exploration in the Aldridge Formation is the contact between the Lower Aldridge and the Middle Aldridge which corresponds to the depositional time of the Sullivan deposit. In this particular area of the Purcell basin, the contact between the lower and middle Aldridge is somewhat enigmatic in that there is no recognizable facies change.
Structurally, the Sha occurrence lies to the east of the Iron Range fault and is encompassed within the east limb of the Goat River anticline. The regional strike of the Aldridge Formation near this occurrence is north, with gentle dips.
Mineralization consists of disseminated sphalerite and rare chalcopyrite occurring within quartz wacke turbidite sequences with argillaceous tops. Associated sulphides are pyrrhotite and pyrite. Mineralization occurs in two thin zones (less than three centimetres) in the diamond-drill hole (Assessment Report 16769). A weak anomaly from a UTEM (University of Toronto electromagnetic) survey was the initial focus of interest on the property (Assessment Report 15428).
During 2004 through 2012, Eagle Plains Resources Ltd. completed programs of geological mapping, geochemical (soil and rock) sampling and airborne geophysical surveys on the area as apart of the Iron Range property. A completed property exploration history can be found at the O-Ray (MINFILE 082FSE017) occurrence.
