The Unlikely occurrence is located along the main road on the north shore of Cariboo Lake, approximately 2.25 kilometres southwest of the small community of Keithley Creek.
The Unlikely occurs within the Late Proterozoic to Paleozoic Snowshoe Group, a dominantly siliciclastic package of continental derivation that most likely represents the distal western edge of Ancestral North America. This fault-bounded sequence is stratigraphically distinct from other packages around it and as such has been called the Barkerville subterrane, a subset of the Kootenay terrane, with which it shares many similarities. East of the Snowshoe Group, across the westerly-verging Pleasant Valley thrust, are rocks of the Kaza, Cariboo and Black Stuart groups, which also contain an abundance of siliciclastics, but with facies that suggest a more proximal continental shelf setting. Many of these units can be correlated with similar stratigraphy within ancestral North American rocks. These rocks are placed within the Cariboo subterrane, representing, like the Cassiar terrane to which it belongs, a displaced piece of ancestral North America. The west flank of the Snowshoe Group is occupied by the Quesnel terrane, a composite volcanic-arc sequence dominated by Mesozoic mafic to intermediate volcanic rocks. It is separated from the Snowshoe Group by the easterly-directed Eureka thrust fault, along which are slivers of mafic and ultramafic rocks assigned to the Crooked amphibolite. This latter package has been correlated with rocks of the Slide Mountain terrane, an assemblage of ocean floor volcanic and sedimentary rocks that structurally straddle the Barkerville and Cariboo terrane lithologies along the Pundata thrust, north of Wells.
The Unlikely showing is hosted by a subdivision of the Snowshoe Group called the Harveys Ridge succession. This unit is dominated by dark-grey to black, carbonaceous phyllites and siltstones, together with dark quartzite and lesser limestone and mafic to intermediate mafic volcanics. This unit is also host to the Frank Creek Cu-Zn-Pb-Ag-Au massive sulphide occurrence, which occurs only 6 kilometres to the east and is believed to represent Besshi-style mineralization.
Hostrocks are grey to dark-grey or black phyllites and siltstones. Locally, immediately adjacent to the sulphides, is a "stripped" sequence of alternating light-grey to white and dark-grey siltstone from 0.5 to 1 centimetre thick. Green-mica–bearing, ankerite-altered and silicified(?) horizons up to several metres thick occur structurally above the showing. Chemical analyses suggests these are highly altered mafic volcanic sequences originally of alkaline composition.
The showing is approximately 1.5 metres wide at its thickest point and gossanous sediments and sulphides can be traced for approximately 10 to 15 metres. The strike of the sulphide horizon is parallel to schistosity or cleavage presumably of second phase origin. Bedding is tightly folded locally, but is essentially parallel to the main schistosity. The mineralized zone is highly siliceous and appears to be silicified Harveys Ridge lithologies. The southwest part of the mineralized zone contains the highest concentrations of sulphides, with one 1.5 by 3-metre area containing zones of greater than 50 per cent sulphide, and averaging between 20 and 50 per cent. Sulphide content decreases to the northeast and disappears into the "stripped" Harveys Ridge lithology described above.
Sulphides consist of pyrite, pyrrhotite, arsenopyrite and chalcopyrite. Copper content varies from 0.05 to 0.3 per cent and some of the higher copper values are associated with anomalous gold (Fieldwork 2001). Sulphides commonly appear finely disseminated and have a dull lustre, although they are locally recrystallized into coarser masses. Sulphides also form more concentrated horizons or discontinuous lenses parallel to the main schistosity.
Barker Minerals Ltd. began exploration programs in the area in 1999. Most of their early efforts focused on the Frank Creek showings (MINFILE 093A 152, 093A 231) to the east on the south side of Cariboo Lake. In 2004, the SCR (MINFILE 093A 203), Peacock (MINFILE 093A 133) and Unlikely showings were briefly examined as part of Barker Minerals Ltd.’s Frank Creek exploration program.
In 2003, a sample from the Unlikely occurrence assayed 0.16 per cent copper, while another sample taken approximately 90 metres to the south east yielded 0.83 per cent copper (Turna, R. (2008-03-29): Technical Report on Frank Creek Property, SCR and Peacock (Rollie Creek) Prospects).
In 2014, work outlined two mineralized horizons similar to those at the Frank Creek (MINFILE 093A 152) occurrence. Dark grey to black phyllites and siltstones host sulphides consisting of pyrite with minor chalcopyrite. In 2015, a flash flood on Two Mile Creek scoured the creek bed from Two Mile Lake down, exposing new mineralized outcrops. That year, Barker Minerals Ltd. collected 49 rock samples from the Upper and Lower Falls areas. Samples from the Lower Falls area, approximately 600 metres west of the Unlikely showing, assayed up to 9.32 per cent copper and 0.068 per cent zinc (Assessment Report 36040).
