Distribution:

The Hyland Group comprises a regionally extensive sequence of low grade metasedimentary rocks that occur in the Selwyn Basin of the northern Canadian Cordillera and in adjacent parts of Alaska (Ross et al., 2005). The Selwyn Basin extends for 1000's of kilometres from Alaska through the Yukon, western Northwest Territories and British Columbia, and into the United States (Nelson and Colpron, 2007) (Goodfellow, 2007). The Kechika Trough is a narrow sliver of coeval basinal strata and forms part of the Selwyn Basin. It continues south for ~500 km into British Columbia (Mair et al., 2006). The Hyland Group occurs predominantly in the Yukon Territories (Gordey and Anderson, 1993; Cecile, 2000) and to a lesser extent in the Northwest Territories (Barnes et al., 2007) and British Columbia (Okulitch et al., 2002; Gabrielse, 2003).

Lithology:

The name Hyland Group was proposed for gritty, quartzose clastic rocks (Yusezyu Formation) and overlying maroon dark grey shales (Narchilla Formation) (Gordey and Anderson, 1993).

Relationship:

The Yusezyu, Algae, and Narchilla formations, in ascending order, comprise the Hyland Group of Gordey and Anderson (1993) (Cecile, 2000). The base of the group is not exposed, and as defined in Gordey and Anderson (1993), the top is overlain sharply and conformably by shale of the Lower Cambrian Gulf Lake Formation (Gordey and Anderson, 1993).

History:

The name "Hyland" is derived from the Hyland River which has its headwaters in southern Nahanni map area. The term Hyland Group is intended to replace the informal name "Grit Unit", which has been applied in many palces in the Yukon to undivided late Precambrain rocks characterized by gritty quartzose clastics, commonly maroon shale in their upper part (Gabrielse, 1967a; Green, 1972a; Gabrielse et al., 1973) (Gordey and Anderson, 1993).

References:

Barnes, E.M., Groat, L.A., and Falck, H., 2007. A review of the Late Cretaceous Little Nahanni Pegmatite Group and associated rare-element mineralization in the Selwyn Basin area, Northwest Territories; in, Mineral and Energy Resource Assessment of the Greater Nahanni Ecosystem Under Consideration for the Expansion of the Nahanni National Park Reserve, Northwest Territories; Geological Survey of Canada, Open File 5344, p. 191-202.

Cecile, M.P., 2000. Geology of the northeastern Niddery Lake map area, east-central Yukon and adjacent Northwest Territories; Geological Survey of Canada, Bulletin 553, 120 p.

Gabrielse, H., 1967a. Tectonic evolution of the northern Canadian Cordillera; Canadian Journal of Earth Sciences = Journal Canadien des Sciences de la Terre, vol. 4, no. 2, pp. 271-298.

Gabrielse, H., 2003. Geology, Kechika River, British Columbia; Geological Survey of Canada, Open File 1633, 2 sheets.

Gabrielse, H., Blusson, S.L., and Roddick, J.A., 1973. Geology of the Flat River, Glacier Lake and Wrigley Lake map-areas, District of Mackenzie and Yukon Territory; Geological Survey of Canada, Memoir 366 (Parts I and II), 421 p.

Goodfellow, W.D., 2007. Base metal metallogeny of the Selwyn Basin, Canada; in, Goodfellow, W.D., ed., Mineral Deposits of Canada: A Synthesis of Major Deposit-Types, District Metallogeny, the Evolution of Geological Provinces, and Exploration Methods: Geological Association of Canada, Mineral Deposits Division, Special Publication No. 5, p. 553-579.

Gordey, S.P. and Anderson, R.G., 1993. Evolution of the northern Cordilleran miogeocline, Nahanni map area (105I), Yukon Territory and District of Mackenzie; Geological Survey of Canada, Memoir 428, 214 p.

Green, L.H., 1972a. Geology of Nash Creek, Larsen Creek, and Dawson map-areas, Yukon Territory; Geological Survey of Canada, Memoir 364, 157 p.

Hofmann, H.J., Cecile, M.P., and Lane, L.S., 1994. New occurrences of Oldhamia and other trace fossils in the Cambrian of Yukon and Ellesmere Island, arctic Canada; Canadian Journal of Earth Sciences = Journal Canadien des Sciences de la Terre, vol. 31, no. 5 (May), pp. 767-782.

Mair, J.L., Hart, C.J.R., and Stephens, J.R., 2006. Deformation history of the northwestern Selwyn Basin, Yukon, Canada: Implications for orogen evolution and mid-Cretaceous magmatism; Geological Society of America, Bulletin, v. 118, no. 3/4, p. 304-323.

Nelson, J. and Colpron, M., 2007. Tectonics and metallogeny of the British Columbia, Yukon and Alaskan Cordillera, 1.8 Ga to the present; in, Goodfellow, W.D., ed., Mineral Deposits of Canada: A Synthesis of Major Deposit-types, District Metallogeny, the Evolution of Geological Provinces, and Exploration Methods; Geological Association of Canada, Mineral Deposits Division, Special Publication 5, p. 755-791.

Okulitch, A.V., Gabrielse, H., MacIntyre, D.G., and Taylor, G.C., 2002. Geology, Ware, British Columbia; Geological Survey of Canada, Open File 4276, 1 sheet, 1:250,000.

Ross, G.M., Friedman, R. and Mortensen, J.K., 2005. Detrital zircon and monazite from the Hyland Group northern Canadian Cordillera and Alaska: Evidence for intracordilleran "Grenville" basement; Geological Society of America, Abstracts with Programs, vol. 37, no. 4, p. 56.