Structural settings and geochemistry of the Myschka gold prospect, Tintina Gold Belt, Mt. Selous area (105K/16, 105N/1), Yukon
Description
The Myschka property overlies a large mineralized area within and adjacent to a 1200 m by 600 m Cretaceous Tombstone Suite granodioritic intrusion. Mineralization is controlled by at least four wide east-west-trending lensoid zones of faulting, brecciation and hydrothermal alteration. Just north of the intrusion, the zones were followed for a distance of 1500 m; widths of individual zones vary from 20 to 100 m. The zones tend to coalesce into much wider (up to 200 m) brecciated packages that dip steeply (70-85°) to the south and apparently crosscut the intrusive. A network of northerly dipping fault and alteration zones crosscut these breccias.
The breccias include intensive quartz stockwork and thicker quartz-filled shear zones containing disseminated gold-bearing sulphide (pyrite, arsenopyrite) mineralization. Rock samples returned numerous strongly anomalous gold values ranging from 200 ppb to 1.05 g/t throughout the extent of the breccia zones. Larger quartz veins locally exhibit much stronger sulphide enrichment, resulting in higher Ag, Bi, Sb, Pb, Zn and Cu values influencing property-scale geochemical zonation. A distinctive gold and pathfinder element soil anomaly is coincident with the breccia packages.
During the 2002 exploration program, the prospect was advanced to drill-ready stage. Proposed drilling will test subsurface continuation of gold-bearing fault/breccia and alteration zones into the intrusive rock.