TUE MAEQUETTE lEON-BEAEING DISTRICT. 



Sf'HOOLCRAFT, Henry E. Narrative journal of travels from Detroit uorthwest 

 through the great chain of American lakes to the sources of the Mississippi River, 

 in the year 1820. Albany, 1821. Pages 157-160. With map and plates. 



The first reference to the geology of the Marquette district is found in 

 a ^•ohuue by Schoolcraft, who, in the course of his travels along the south 

 shore of Lake Superior, as a member of the exploring party linder Grovemor 

 Cass, of Michigan, observed the existence of granite at the point now known 

 as Granite Point, some 9 or 10 miles north of the present city of Marquette, 

 and the unconformity between it and the sandstone immediately overlying 

 it. The granite, "rising out of the lake to a height of 200 feet, is connected 

 with the shore by a neck of land consisting of red and gray sandstone in 

 horizontal layers." Greenstone veins, varying in width from 2 to 30 feet, 

 were noticed cutting the granite. "The sandstone laps upon the granite, 

 and fits into its irregular indentations in a manner that shows it to have 

 assumed that position subsequently to the upheaving of the granite. Its 

 horizon tali ty is perfectly preserved, even to the immediate point of contact, 

 which is laid bare to the view." A geological section is published, showing 

 the unconformity of the sandstone on the granite. The author does not 

 pretend to know the age of the sandstone, but he thinks "its position would 

 indicate a near alliance to the 'Old Red sandstone.'" The country back of 

 the lake appeared to Schoolcraft to consist largely of granite. 



Thus the existence of granite cut by trap dikes in the Marquette region, 

 and of sandstone much younger than the granite, was first made known by 

 Schoolcraft, who also pictured and made classical one of the best-known 

 unconformities on Lake Superior. 



Bayfield, H. W. Outlines of the geology of Lake Superior. Trans, of the 

 Lit. and Hist. Soc. of Quebec, Vol. I, 1829, pages 1-43. 



Commander Bayfield, in 1829, on his tour around the lake, made a 

 numljer of observations concerning the geology of its coasts. He confirms 

 Schoolcraft's discovery of the existence of granite at Granite Point and of 

 horizontal sandstone resting immediately upon it. He finds this same 



