The Hatsoff occurrence is located approximately 40 kilometres southwest of Invermere in the Golden Mining Division. The property is situated at 2900 metres elevation above sea level 2 kilometres east of a lake locally known as the Lake of the Hanging Glacier.

Regionally, the area is underlain by Proterozoic clastic sedimentary rocks of the Purcell and Windermere supergroups and by lower Paleozoic strata of the Beaverfoot and Mount Forster formations (Geoscience Map 1995-1).

The Purcell Supergroup strata include the Aldridge, Creston, Kitchener, Dutch Creek and Mount Nelson formations. The Windermere Supergroup unconformably overlies the Purcell Supergroup rocks and includes the Toby Formation and Horsethief Creek Group (Paper 1990-1).

In the vicinity of the occurrence, rocks of the Kitchener and Dutch Creek formations have been further subdivided and assigned to the Van Creek and Gateway formations. The Van Creek Formation correlates with the Lower Kitchener Formation while the Gateway Formation is equivalent to the lower portion of the Dutch Creek Formation. The Mount Nelson Formation has been subdivided into seven discrete members, a lower quartzite, a lower dolomite, a middle dolomite, a purple dolomite, an upper middle dolomite, an upper quartzite, and an upper dolomite (Open File 1990-26).

Rocks of the Horsethief Creek Group, Beaverfoot and Mount Forster formations are folded and overthrusted by rocks of the upper portion of the Dutch Creek Formation and the lower members of the Mount Nelson Formation. The sedimentary rocks have undergone regional metamorphism to at least greenschist facies.

Near the occurrence, the sedimentary rocks of the Dutch Creek and Toby formations and of the Horsethief Creek Group have been intruded by the Cretaceous Hanging Glacier stock.

The Hanging Glacier stock is 1.5 kilometres in diameter and consists of quartz, biotite, plagioclase and potassium feldspar phenocrysts. The overall composition is that of quartz monzonite. A coarse-grained granodiorite phase is developed near the contact of the stock and a number of small porphyritic quartz monzonite plugs have intruded the stock near its eastern contact.

Molybdenite mineralization occurs in pyritic quartz stockwork associated with the porphyritic quartz monzonite plugs and within argillite of the Horsethief Creek Group rocks next to the intrusion. The stockwork is structurally controlled and associated with strong phyllic alteration of the quartz monzonite. Fluorite and sphalerite are also present in minor amounts within the stockwork (Assessment Report 7534).