DESCRIPTION OF THE AREAS 283 



RICE LAKE-WANIPIGOW RIVER AREA^o 



The Eice-Wanipigow area lies in the southeastern part of the province ; 

 it has attracted considerable attention on account of the large number of 

 gold prospects which have been staked in the area. Geological work was 

 performed in the area in 1912 by Moore, in 1916 by Dresser, in 1917 by 

 Marshall, and by Colony, De Lury, and McCann in 1920. 



The oldest rocks are lava flows, which in places show well marked 

 ellipsoidal structure. They have been intruded by quartz-porphyry, 

 quartz-feldspar porphyry, and feldspar-porphyry. All these rocks are 

 intruded by hornblende granite, which is in turn intruded by norite.^^ 

 Near the granite the volcanic rocks have been altered into glistening, 

 black hornblende-schist. Except at the contact and in local areas, the 

 rocks are massive. 



Schists and gneisses which are considered of sedimentary origin have 

 been observed at a number of places in the area. They are of fine texture 

 and predominantly of a red color. In thin section they are found to 

 consist of quartz, fresh orthoclase and acid plagioclase, brown biotite, 

 muscovite, and garnet. A band of conglomerate 30 feet thick outcrops 

 on Slate Lake. It consists of a gray-green matrix with pebbles of green- 

 stone, quartz, jasper, and porphyry fragments. It is highly metamor- 

 phosed. According to Marshall, it rests unconformably on what appears 

 to be a feldspar porphyry. Other outcrops of conglomerate are described 

 by Moore. The sedimentary rocks are grouped together by him under 

 the term Wanipigow series, placed above the volcanic rocks which he 

 correlates with the Keewatin. The volcanics and sediments are all in- 

 truded by granite, granite-gneiss, and pegmatite. 



STAR LAKE AREA 



The Star Lake area lies in the extreme southeastern corner of Mani- 

 toba, immediately south of the Canadian Pacific Railway. 



No detailed geological mapping or study has been made, but the area 

 has been visited by Wallace and De Lury for the Public Utilities Com- 

 mission of Manitoba, and by Marshall and Bruce, of the Geological Sur- 

 vey, who have reported on the claims staked for gold, molybdenite, 

 scheelite, and platinum. 



The oldest rocks of the region are ellipsoidal lavas and derived schists, 

 with which are associated some areas of sedimentary rocks. The latter 

 include conglomerate which contains pebbles of the volcanic rocks as well 



i»E. S. Mooi'e : Geol. Surv. Can., Sum. Rept., 3912, p. 262. 



"R. J. Colony: Bull. Can. Inst. Min. and Met., no. 103, November, 1920, p'. 862. 



