The Edozadelly Mountain occurrence, composed of radioactive materials in a tuff unit of the Lasuli Member, Brothers Peak Formation (Sustut Group), is located 3 kilometres west-northwest of Edozadelly Mountain and 8 kilometres west-southwest of the confluence of Chapea Creek with the Stikine River, about 248 kilometres north-northwest of the community of Germansen Landing.

The Edozadelly Mountain showing lies on the eastern edge of the Sustut Basin. It is composed of mid-Cretaceous to latest Cretaceous non-marine strata of the Sustut Group. The Sustut Basin is a successor basin to the larger Bowser Basin to the west. The Bowser Lake Group consists of Middle Jurassic to mid-Cretaceous marine and non-marine strata. Both groups and underlying strata of Stikinia were deformed by northeast-verging folds and thrust faults of the Skeena Fold Belt in Late Jurassic(?) to latest Cretaceous or early Tertiary time (Geological Survey of Canada Paper 92-1A, pages 77-84).

Continental clastic sediments of the Sustut Group are subdivided into the Tango Creek and overlying Brothers Peak formations. The Tango Formation is subdivided into two members; the lower Niven Member and the upper Tatlatui Member. The Brothers Peak Formation is subdivided into the lower Lasuli Member and the upper Spatsizi Member.

The lower Lasuli Member is composed of coarse, grey, polymictic conglomerate and arenites, interbedded with grey, green and rarely varicoloured ash tuffs and tuffaceous mudstones and siltstones. The tuff units are radioactive with some zones 2 to 10 centimetres thick, over 500 metres strike length, yielding over 0.01 per cent uranium (Geological Survey of Canada Paper 81-1A, page 245). The lowermost 6 or 7 ash tuff units of the Lasuli Member are anomalously radioactive. These tuffs are generally laminated, greenish grey, porcelaneous and hard, and weather cream to pale brown. The more radioactive tuffs and tuffaceous mudstones are marked by pink layers or mottles. The most radioactive are altered to a bright red, contain coaly fragments, and are within sequences containing white spherules and coalescent spherules of analcime (zeolites).

A sample of the tuff analyzed about 0.038 per cent uranium over a 2-centimetre thick layer. Radioactive inspection suggests that all tuffs in the Lasuli Member yield about 0.002 to 0.006 per cent uranium. Uranium mineralization is likely early diagenetic, but essentially syngenetic within waterlain tuffs.