SRK structural and resource geologists work closely with clients to deliver resource estimates that incorporate sophisticated geological and structural models. Since 2007, SRK has assisted Rainy River Resources Ltd. to develop detailed resource evaluations for the Rainy River deposit based on evolving, constrained structural models. The Rainy River deposit is a strongly deformed, gold-rich volcanic massive sulfide-associated gold deposit located in northwestern Ontario, Canada. The deposit consists of a number of distinct resource zones, the largest being the ODM17 zone.
In 2008, SRK was commissioned to undertake a revised resource estimate for the Rainy River deposit. As an integral component of this process, SRK geologists visited the project site and conducted a structural interpretation based on unoriented drill core. Evidence for a penetrative south-dipping foliation, accompanied by a strong southwest-plunging stretching lineation that overprinted the gold mineralisation, were critical observations. Most styles of gold mineralisation in the ODM17 zone are clearly deformed by this strong ductile deformation, and both sericite alteration halos and gold mineralisation envelopes plunge approximately parallel to the stretching lineation. The initial resource modelling incorporated these structural observations to define a series of geodomains consistent with the foliation and stretching lineation orientations.
In 2010, SRK was commissioned to undertake a further structural study. At this time, SRK was able to integrate recently acquired Optical TeleviewerTM and oriented core programs into the geological interpretation. SRK and Rainy River personnel confirmed the strong southwest-plunging lineation and delineated distinct domains, consisting of slightly different foliation orientations within the ODM17 zone. High strain zones at the structural base of the ODM17 zone and bounding internal zones of increased gold mineralisation were traced through the deposit. These observations were used as the geological rationale for constructing better constrained resource domains (Figure 1). The practical implementation of detailed structural analysis resulted in a resource model with increased geological confidence that reduced the level of risk associated with the resource estimate.
