The property is largely underlain by Cretaceous Coast Intrusion granodiorite to diorite which overlies a wedge of Precambrian Yukon Group metasedinents on the northeast side of Mt. Anderson. On the north face of Mt. Anderson a small Tertiary rhyolite plug intrudes granodiorite and a swarm of Tertiary rhyolite dykes intrude the granodiorite near the western summit of the property. These structures are considered to be part of the rim of the Mt. Skukum caldera complex.
The Cretaceous granodiorite to diorite is complexly fractured and jointed near the north face and grades to diorite or quartz diorite on the south part of the property. Clay and chlorite alteration is most pervasive on surface and in close proximity to quartz veins, zones of silicification, mineralization and dyke intrusions.
The nearby (3 kilometre east) Tally-Ho shear zone is a deep crustal structure up to 4 km wide.
During a late Cretaceous-early Tertiary stage of brittle deformation, quartz veins developed on Mt Anderson in extensional fractures of this zone. Later Eocene deformation resulted from doming and subsequent crustal collapse in the Mt Skukum Volcanic Complex. These resulting structures served as conduits for significant hydrothermal flows and mineral deposition.
The granodiorite and diorite host rocks on Mt Anderson are intruded by at least two types of quartz veins, mesothermal vein systems, which appear to be found only on the northern part of the property and agate-fluorite epithermal veins occurring on the southern portion of the claims. The vein systems are readily distinguished in the field by the presence of sulphide and white bull quartz in the mesothernal veins and by the laminar, agate silica textures and lack of visible sulphides in the epithermal system. Mafic dykes described as basalt to porphyritic andesite as well as rhyolite dykes usually accompany the mesothermal quartz veins.
These two vein systems appear to be separated by a major east trending structure running through the property. To the east, the Goddell fault is a steeply dipping, east-southeast trending fault system that is developed in pre-Tertiary.rocks over a minimum 5 km strike length. Further faults developed along strike from it to the east of Becker Creek onto Mt Anderson and may represent its eastern continuation. Like other east-trending faults in the area, the Goddell fault is intruded by rhyolite and andesite dykes along its length and has associated Au-Ag and Sb mineralization developed at Goddell Gully and Becker-Cochran, respectively. The Au-Ag quartz veins on Mt Anderson are geologically very similar to those deposits already identified on this fracture zone.
The most significant shear-hosted gold/silver bearing quartz veins discovered on Mt Anderson is the “Whirlwind” vein system which has been traced for 1200 meter of strike length. The Whirlwind vein system is considered mesothermal and includes all veins north and west of the “Forty-seven” zone. This system typically consists of white, bull quartz with clay alteration at vein contacts, usually accompanied by basalt to andesite dykes. The nature of the veins is pod like to pinching and swelling up to 3 metres wide. Massive, high grade galena, sphalerite and tetrhedrite is found in pods up to 1.2 meters wide in the “47” zone. Disseminated, stringer, and pods of galena are found within the quartz veins throughout the strike length of the Whirlwind vein system.
An epithermal quartz vein outcrops for 100 meters in granite on the south west corner of the claims. The agate-fluorite vein carries slight precious metal enhancement on surface and at depth. It is 1meter wide on surface and expands to 2 meters at a depth of 70 meters. Fluorite changes in colour from green to purple and clay alteration occurs along the vein margins. Agate textures and vein structure are continuous with depth.
Shear zones containing botryoidal quartz/agate have been discovered throughout the southern portion of the property indicating high level epithermal systems in the area.
A five meter wide, gold silver bearing quartz/agate vein, has been uncovered on a knoll above the botryoidal zone. It is located within a highly silicified, limonite and manganese stained shear zone uncovered for a strike length of 50 meters and open on strike in both directions.
