188 SEVENTH REPORT. 



THE BLACK RIVER SECTION NEAR BESSEMER. 



W. C. GORDON. 



During the months of Jul^', August, September,. and a part of October 

 the Mich. Geol. Survey had a party of men making a section of the 

 Keweenawan rocks as they are exposed between the city of Bessemer 

 and Lake Superior. It is the attempt of this paper to give some idea 

 of the work done by that party. 



Bessemer is a city of about 4000 population, lying for the most 

 part in S. 10 T. 47 nI, R. 4G W. It is on the C. & N. W., and Wis. Cent. 

 Ry's. and is entered by a spur line of the D. S. S. & A., the main 

 line of which passes two miles to the north. It is an iron-mining town 

 on the Gogebic Iron Range. Six miles to the west of it is the Wisconsin 

 state line. 



Immediately around the village the land is cleared and under culti- 

 vation, but the I). S. S. & A. Ry. marks the northern limit of cleared 

 land, beyond which is the virgin forest. 



Just north of, and passing so close as to almost touch the city lim- 

 its, is an east and west ridge rising from 200 to 250 feet above the sur- 

 rounding country. In places it develops into steep bald hills, and even 

 bluffs. The ridge is broken through frequently by north and south gaps 

 which vary in width from a few hundred yards up to a mile. These 

 gajjs immediately suggested to Dr. Lane the possibility of north and 

 south faults, and later investigation proved the suggestion a true one. 

 North of this ridge the country is flat and drift covered for about six 

 miles ; or, if we may express it so, there is a gap six miles wide extending 

 east and west. Beyond this gap is again hill country, but not a con- 

 tinuous ridge. To the west is an isolated peak whose eastern side pre- 

 sents a cliff of felsite about 100 feet high, the hill itself rising nearly 

 250 feet. This hill is known as Chippewa Bluff. Eastward from this 

 bluff, and about two miles away, is a hill of basic rock having about 

 the same elevation. The rather broad top of this hill makes it have 

 somewhat the appearance of a highland. BetAveen these last two hills 

 is a north and south gap. Directly north of Chippewa Bluff, and distant 

 about three iniles. is a conglomerate ridge whose longer axis extends east 

 and west. This ridge is about two miles long. Beyond it, and not far 

 distant, is Lake Superior. 



Black River enters the area worked just north of the east and west 

 ridge spoken- of above. After flowing westward, practically along the 

 foot of this ridge, for about three miles it turns northward and soon 

 swings somewhat to the east. It flows to the east of Chippewa Bluff, 

 taking to the low land that lies between it and the highlands that lie 

 to the east. As it continues its northern course it is forced still further 

 east around the conglomerate ridge, after which it takes a direct route to 

 Lake Superior. 



The river is from one hundred to one hundred and fifty feet wide, 

 but is very shallow. During the low water of August, even a small row- 



