The Panorama South prospect extends from latitude 56 degrees north 43 minutes to 56 degrees north 47 minutes and longitude west 128 degrees 20 minutes to 128 degrees west 38 minutes covering the Panorama Creek drainage basin. The occurrence forms part of the southeast Groundhog coalfield, an oblong (roughly 30 by 80 kilometres) area extending from the headwaters of the Klappan and Little Klappan rivers southeast to Groundhog Mountain. Refer to the Discovery deposit (MINFILE 104A 078) for an overview of the exploration history, and regional and local geology of the Groundhog coalfield. The coal seams form part of the Lower Cretaceous Currier Formation (Bowser Lake Group, Muskaboo Creek assemblage) comprising carbonaceous shale, siltstone and sandstone.
In 1980, prospecting, mapping, trenching and some drilling of the Panorama South occurrence by Gulf Canada resulted in a speculative reserve estimation of 218 million tonnes. Upwards of nine coal seams were encountered, however, the above reserve estimation was based on the dimensions of the Currier and Leach seams (average thickness of 2.10 and 1.97 metres, respectively). In 1981, a revised inferred estimate of 240 million tonnes for the combined Panorama South and North (MINFILE 104A 085) properties was made. The most favourable area on the Panorama South property lies on Cushing Ridge approximately 3 kilometres southeast of Panorama Lake.
Dawson and Ryan (Geological Survey of Canada Open File 2555) trenched and sampled four occurrences in the Panorama South area in 1991. In those trenches coal seams range in thickness from 1.1 to 1.5 metres, and vitrinite reflectance values range from 2.79 to 2.93% Rmax (semi-anthracite rank).
The anthracite deposits at the Panorama South prospect are part of the southern Groundhog Coalfield near the north end of the Bowser Basin of British Columbia. The Bowser Basin was filled with sediments deposited from eroding mountains during the late Jurassic and early Cretaceous. At the northern end of the basin, peat formation occurred in deltaic environments. These peat bogs were metamorphosed to form the coal-bearing sequences of the Groundhog Coalfield, an oblong (30 by 80 kilometres) area extending southeastwards from the headwaters of the Klappan and Little Klappan rivers to Groundhog Mountain in the Skeena Ranges, an area characterized by mountainous terrain with broad valleys.
The coal-bearing sequences of the Groundhog Coalfield reach approximately 1100 metres in thickness, with 33 identified coal horizons of up to 11.8 metres in true thickness interbedded with primarily mudstone, siltstone and sandstone. The coal-bearing units and surrounding beds were later deformed by compression that created open to tight folds that are near vertical to overturned to the northeast. Fold axes strike 30 to 60 degrees to the northwest and axial planes dip 25 to 85 degrees southwest. The folds are cut by thrust faults striking 20 to 40 degrees to the northeast and dipping 10 to 25 degrees southwest. The whole area is cut by younger high-angle faults trending northwest, north and northeast.
Coal rank in the Groundhog Coalfield varies from semi-anthracite to anthracite. Coalification proceeded to the extent that coking and agglomerating properties of the coal are severely reduced. However anthracite has high heat value and is used in metallurgical processes such as sintering pulverized coal injection (PCI). It is also used in filter media, briquettes, and in coal gasification.
Coal quality tests (Coal Assessment Report 112) based on trench samples gave the following average values:
------------------------------------------------------------ Raw Coal Washed Coal Fixed carbon 55.9 65.6 Ash content 22.6 14.0 Volatile matter 17.8 18.2 Sulphur content 0.5 0.6 Calorific value 5205 5833 ------------------------------------------------------------- |
All values are in per cent except for the calorific value which is in calories per gram. Washed values are based on a specific gravity separation of 1.8 grams per cubic centimetre which gave a float yield of 82.5 percent. Vitrinite reflectance indicates anthracite rank.
Coal occurrences in the Panorama South area are hosted by the Upper Jurassic Muskaboo Creek assemblage of Evenchick and Thorkelson (Geological Survey of Canada Bulletin 577). The Muskaboo Creek is a shelf assemblage, comprising sandstone, siltstone, and conglomerate and minor coal; the primary lithofacies is sandstone.
The nomenclature of the coal-bearing rock units in the Groundhog Coalfield has a complex history. It has been variously referred to as the Currier Formation (Bustin and Moffat Canadian Society of Petroleum Geologists Bulletin 1983; Macleod and Hills, Canadian Journal of Earth Sciences 1990, and most industry Coal Assessment Reports), the Groundhog-Gunanoot facies (Eisbacher, Geological Survey of Canada Paper 73-33), the Gunanoot Assemblage (Richards and Gilchrist, Geological Survey of Canada Paper 79-1B), and the Groundhog-Gunanoot Assemblage (Evenchick and Thorkelson, Geological Survey of Canada Bulletin 577, 2005). Evenchick and Thorkelson (Geological Survey of Canada Bulletin 577) provide a history of stratigraphic nomenclature in the coalfield, and a discussion of the debate over the age of the coal-bearing unit, which they refer to as the Groundhog-Gunanoot assemblage. The age is not well-constrained, and may vary by area; however it is mainly between latest Jurassic and late Early Cretaceous.
