Distribution:

The Wollaston Domain is one of several tectonostratigraphic domains that comprise the Hearne segment of Chuchil Craton in Saskatchewan. It comprises a north-northeast-trending succession of tightly folded Paleoproterozoic metasedimentary rocks overlying late Archean granitic gneiss, extending southwest from Nueltin Lake in northern Manitoba and Nunavut, through Wollaston Lake, and beneath the Phanerozoic strata of the Western Canadian Sedimentary Basin at least as far as the South Saskatchewan River (Yeo and Delaney, 2007).

Lithology:

The rocks of the supergroup consist of four uncoformity-bounded Paleoproterozoic siliciclastic metasedimentary sequences, which include minor carbonate and volcanic rocks. The Wollaston Supergroup consists of, in ascending order, the Courtenary Lake Group, the Souter Lake Group, the Daly Lake Group (George Lake, Spence, Karin Lake, Bole Bay, Thomson Bay, Roper Bay and Burbidge formations) and the Geikie River Group (Janice Lake, Rafuse Lake, Fraser Lakes and Causier Creek formations, and Hidden Bay Assemblage) (Yeo and Delaney, 2007).

Age Determinations:

Method - U/Pb; Material - Zircon; Technique - SHRIMP; Age - 2075; Err_Minus - 2; Err_Plus - 2..

Relationship:

The Wollaston Supergroup overlies Archean gneiss along the eastern margin of the Hearne Province. It comprises four groups, separated by well documented, major unconformities. The Courtenay Lake and Souter Lake groups are isolated between basement inliers and the eastern margin of Wollaston Domain; the Daly Lake and Geikie River groups are extensive over most of the domain. The last two groups correspond approximately to the lower pelitic succession and the upper psammitic succession recognized by Ray (1979), Lewry and Sibbald (1980), and other workers. Recent work, howver, has shown that a much more detailed correlation of regionally extensive, mappable, lithostratigraphic units (i.e. formations) can be made (Yeo, 1998); Yeo and Savage (1999); Tran (2001); Tran et al. (2003)). Fourteen such formations are distinguished within the four groups that comprise the Wollaston Supergroup. Overlapping geochronological events and proximity suggest tectonostratigraphic relationships with Wollaston Domain strata in Manitoba, the Campbell River Group of Pater Lake Domain and metasedimentary rocks of Rottenstone Domain to the east, and the intracratonic basin Hurwitz Group to the north (Yeo and Delaney, 2007).

History:

Money (1968) first described the Wollaston Domain and its supracrustal rocks as a major tectonostratigraphic feature in northern Saskatchewan and Manitoba. He distinguished three regional metasedimentary assemblages in the Wollaston Lake fold belt: the "eugeosynclinal" Sandfly Lake Group (Money, 1968), the overlying "stable shelf" Meyers Lake Group (Money, 1965), and the extensive, "miogeosynclinal" Daly Lake Group (Money, 1966, 1968). Scott (1970) recognized two low-grade sedimentary assemblages in the Courtenay Lake area along the eastern margin of the belt, the Courtenay Lake and Souter Lake groups, interpreted to be correlative with Money et al.'s (1970) Sandfly Lake and Meyers Lake groups, respectively. Later workers (Munday, 1974, 1978; Gilboy, 1975, 1982; Ray, 1975, 1977, 1980), however, were unable to distinguish those three successions in the higher metamorphic grade rocks farther west in Wollaston Domain. Not recognizing that the Sandfly Lake-Courtenay Lake and Meyers Lake-Souter Lake assemblages are restricted to the eastern margin of Wollaston Domain, they proposed that the earlier nomenclature be abandoned and that all the supracrustal rocks be combined into a single succession, the Wollaston Group (Ray, 1975, 1979; Gilboy et al., 1976). Subsequently, Ray (1979) recognized that Money and Scott were correct in distinguishing the strata along the eastern margin of the domain from the supracrustal rocks to the west. Rather than revive their original nomenclature, Ray (1979) proposed the name Needle Falls Group for the former succession, while restricting the Wollaston Group to the strata originally called the Daly Lake Group. The name Wollaston Group has continued in use in both this restricted sense and in its original sense as a name for the entire supracrustal succession. Wheras inclusion of the entire supracrustal assemblage in the Wollaston Group has become entrenched by usage (e.g. MacDonald and Simmon, 1999), Yeo and Delaney (2007) propose that this usage be formalized by recognizing a Wollaston Supergroup that includes all of the supracrustal rocks in the Wollaston Domain (Yeo and Delaney, 2007).

References:

Annesley, I.R., Madore, C., and Krogh, T.E., 1992. U-Pb geochronology of some granitoids from the Peter Lake Domain: a summary; in Summary of Investigations 1992; Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 92-4, p. 168-171.

Fossenier, K., Delaney, G.D., and Watters, B.R., 1994. Lithogeochemical investigations of volcanic rocks and age of their host sediments, Lower Proterozoic Courtenay Lake-Cairns Lake Fold Belt, Courtenay Lake, Saskatchewan; in Summary of Investigations 1994; Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 94-4, p. 63-69.

Fossenier, K., Delaney, G.D., and Watters, B.R., 1995. Lithogeochemistry of volcanic rocks from the Lower Proterozoic Courtenay Lake Formation, Wollaston Domain; in Summary of Investigations 1995; Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 95-4, p. 49-60.

Gilboy, C.F., 1975. Foster Lake area; in Summary of Investigations 1975; Saskatchewan Geological Survey, p. 29-34.

Gilboy, C.F., 1982. Geology of an area around Rottenstone and Dobbin lakes; Saskatchewan Energy and Mines, Report 193, 68 p.

Gilboy, C.F., Lewry, J.F., Ray, G.E., and Sibbald, T.I.I., 1976. Rb/Sr dating of rocks from the Wollaston Lake Belt, Saskatchewan: discussion; Canadian Journal of Earth Sciences, v. 13, p. 1643-1645.

Lewry, J.F. and Sibbald, T.I.I., 1980. Thermotectonic evolution of the Churchill Province in northern Saskatchewan; Tectonophysics, v. 68, p. 45-82.

MacDonald, R. and Simmon, W.L., 1999. Geological map of Saskatchewan, 1999 edition; Saskatchewan Energy and Mines, scale 1:1 000 000.

Money, P.L., 1965. The geology of an area around Needle Falls, Churchill River; Saskatchewan Energy and Mines, Report 88, 70 p.

Money, P.L., 1966. The geology of the Daly Lake area (east half), Saskatchewan; Saskatchewan Energy and Mines, Report 108, 48 p.

Money, P.L., 1968. The Wollaston Lake fold-belt system Saskatchewan-Manitoba; Canadian Journal of Earth Sciences, v. 5, p. 1489-1503.

Money, P.L., Baer, A.J., Scott, B.P., and Wallis, R.H., 1970. The Wollaston Lake Belt, Saskatchewan, Manitoba, Northwest Territories; in Symposium on Basins and Geosynclines of the Canadian Shield, (ed.) A.J. Baer; Geological Survey of Canada, Paper 70-40, p. 171-200.

Munday, R.J., 1974. Ile a la Crosse (east) area: reconnaissance geological survey of 73)-NE and 73O-SE; in Summary Report of Geological Investigations by the Saskatchewan Geological Survey; Saskatchewan Department of Mineral Resources, p. 114-119.

Munday, R.J., 1978. The shield geology of the Ile-a-la-Crosse (east) area, Saskatchewan; Saskatchewan Energy and Mines, Report 189, 27 p.

Ray, G.E., 1975. Foster Lake (NE)-Geikie River (SE) area; in Summary of Investigations 1975; Saskatchewan Geological Survey, Saskatchewan Energy and MInes, p. 13-18.

Ray, G.E., 1977. The geology of the Highrock Lake-Key Lake vicinity, Saskatchewan; Saskatchewan Energy and Mines, Miscellaneous Report 78-10, p. 19-28.

Ray, G.E., 1979. Reconnaissance bedrock geology, Wollaston Lake east; in Saskatchewan Energy and Mines, Miscellaneous Report 78-10, p. 19-28.

Ray, G.E., 1980. Geology of the Parker Lake-Nelson Lake vicinity, in Saskatchewan Energy and Mines, Report 190, 40 p.

Scott, B.P., 1970. The geology of the Combe Lake area, Saskatchewan; Saskatchewan Energy and Mines, Report 135, 32 p.

Tran, H.T., 2001. Tectonic evolution of the Paleoproterozoic Wollaston Geoup in the Cree Lake Zone, northern Saskatchewan, Canada; Ph.D. thesis, University of Regina, Regina, Saskatchewan, 458 p.

Tran, H.T., Ansdell, K., Bethune, K., Watters, B., and Ashton, K., 2003. Nd isotope and geochemical constraints on the depositional setting of Paleoproterozoic metasedimentary rocks along the margin of the Archean Hearne craton, Saskatchewan, Canada; Precambrian Research, v. 123, p. 1-28.

Yeo, G., 1998. A systems tract approach to the stratigraphy of paragneisses in the southeastern Wollaston Domain; in Summary of Invesitgations 1998; Saskatchewan Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 98-4, p. 36-47.

Yeo, G.M. and Delaney, G., 2007. The Wollaston Supergroup, stratigraphy and metallogeny of a Paleoproterozic Wilson cycle in the Trans-Hudson Orogen, Saskatchewan; in Extect IV: Geology and Uranium EXploration TECHnology of the Proterozic Athabasca Basin, Saskatchewan and Alberta (ed.) C.W. Jefferson and G. Delaney; Geological Survey of Canada, Bulletin 588, p. 89-117 (also Saskatchewan Geological Soviety, Special Publication 18; Geological Association of Canada, Mineral Deposits Division, Special Publication 4).

Yeo, G.M. and Savage, D.A., 1999. Geology of the Higrock Lake area, Wollaston Domain (NTS 74H-3 and -4); in Summary of INvestigations 1999, Volume 2; Saskatchewan Energy and Mines, Miscellaneous Report 99-4.2, p. 38-54.