The ABC porphyry copper prospect is located on the slope northeast of upper Relay Creek, approximately 35 kilometres north of Gold Bridge.
Regionally, the property is underlain by the Tyaughton Trough, a northwest-trending Sinemurian to Coniacian depositional basin overlapping the Coast Plutonic Complex to the west and the Stikine Terrane to the east. Upper Cretaceous Battle Ridge Group nonmarine sediments and volcanics unconformably overlie Tyaughton Trough strata. The property is approximately 4 kilometres southwest of the northwest-trending Yalakom fault, a major dextral fault displaying oblique displacement.
The mineralization occurs near the southeast margin of a northwest-trending zone of alteration, which measures approximately 10 kilometres long by 2 kilometres wide. The zone is coincident with a swarm of Cretaceous to Tertiary porphyry dikes, sills and small plugs, comprising mainly quartz-feldspar and hornblende-feldspar porphyries. The porphyries intrude sedimentary and volcanic rocks of the Lower Cretaceous Taylor Creek Group and Upper Cretaceous Powell Creek Formation (informal name). The zone of intrusion and alteration is approximately concordant with the northwest-trending structural grain of the area, as defined by numerous steeply dipping faults. These comprise part of a complex fault system associated with the Yalakom fault.
Rocks in the immediate area of the occurrence comprise altered sandstone and shale of the Taylor Creek Group, cut by altered quartz-feldspar and hornblende-feldspar porphyry intrusions. Hydrothermal alteration effects include widespread carbonate alteration and local zones of silicification and pyritization, as well as local kaolinization of feldspars. Pyrite occurs as disseminations and along fracture planes. It is locally accompanied by pyrrhotite and rarely by traces of chalcopyrite. Copper content of analyzed grab samples is less than 0.1 per cent.
In 1970, Sheba Syndicate performed a regional soil and silt geochemical survey, discovering anomalous copper, molybdenum and zinc values. The distribution of anomalies suggested possible porphyry copper-molybdenum mineralization, although aside from widespread pyritization and minor chalcopyrite in outcrop, other mineralization evidence was not found.
In 1972, Edina Resources Ltd. surveyed geology following recent road building, noticing leached, altered and oxidized quartz-feldspar porphyry hosting weak pyrite-chalcopyrite-chalcocite mineralization (Assessment Report 3829).
In 1973, Edina Resources Ltd. conducted detailed geological mapping and a magnetometer survey that identified a small positive anomaly and several faults (Assessment Report 4597).
In June 1988, Bond Gold Canada Inc. conducted 78.5 line kilometres of total field magnetometer and very low-frequency electromagnetic surveys (Assessment Report 18740).
In 1991, Lac Minerals Ltd. conducted geological mapping, rock-chip and silt sampling. Results suggested the potential for localized gold mineralization based upon pyrite and pyrrhotite occurrence and the presence of arsenic-antimony-mercury anomalies (Assessment Report 22311).
