U.S.GEOLOGICAL SURVEY. 



MONOGRAPH XXXVI PL.UI 



MAP OF EXPOSURES 



IN SEC. 7 AND IN PORTIONS OF SECS. 8, 17, AND 18, T. 42 N.,R. 28 W., MICH 1 GAN 



VICINITY OF DAM ON EAST BRANCH OF STURGEON RIVER 



I A. Aitose 



SI. Slate f _ „ 



ARCHEAN - Gr.^Granite ALGONKIAN Q. Qiiartzite INTRUSraj X-^"'''^®^°"'^ „ , . . 



C. Conglomerate iG.S.CBwnstoue Schist 



[ G.T.Greeiistonetuffaceous 



