22 THE MARQUETTE IRON BEAEING DISTRICT 



Jackson received a specimen of pure hematite from near tlie Carp River 

 (pp. 478-4711). The maps that accompany the report are mainly of the 

 copper regions. 



Locke, J. Cnited States geological survey of public lands in Micbigau. Field 

 notes of 1847. Accompanj-ing report of Dr. Jackson. 31st Congress, 1st session, 

 1849-50. Senate Documents, Vol. Ill, No. 1, pages 572-586. 



Ahhoug-li Locke's report, which accompanies that of Dr. Jackson, is 

 but a copy of the author's field notes, it contains a few points of interest 

 concerning the iron region. Locke and his assistants coasted along the 

 shore of Lake Superior from L'Anse to beyond the Chocolate River. At 

 Presque Isle the junction of the trap and sandstone on the east side of the 

 point was observed, and fresher trap dikes in the main "trap mass" were 

 noted. Li the vein mined by the New York and Lake Superior Mining Com- 

 panv is a mixture of galena, asbestos, pyrite, and arsenopyrite. Inland from 

 the mouth of the Carp River a large number of veins of quartz containing 

 copper pyrites were seen cutting metamorphic slates. At the Jackson loca- 

 tion (sec. 1, T. 47 N., R. 27 W.) the direction of the iron range is about east 

 and west. Much ore lies in loose pieces on the surface of the ledges. The 

 best of it is of a loose crystalline structure, Init about one-half consists of 

 "ribbon" ore, striated with red veins, which deserve examination to ascer- 

 tain their character, while a third variety is a slaty ore, compact and pure. 

 Along the west lines of sees. 6 and 7, T. 47 N., R. 26 W., exposures of ore, 

 metamorphic sandstone, and ferruginous quartz were seen. Continuing 

 farther south, the explorers found ores of various qualities, and at the south- 

 west corner of section 18 an "augitic rock." On the east branch of the 

 Escanaba River they ran into "red sienite." About a mile north of the Carp 

 River, near the coast, there occars a clay-slate, which farther north is "highly 

 metamorphic, and a trappean rock occurs, apparently blending with the 

 slate." Trap rocks "seem to l)e frequently interfused with the metamorphic 

 rocks in this region, and sometimes to receive even a stratified structure, 

 when slightly changed from their original type." "With regard to the 

 metamorphosed character of the regioai to wliich these notes * * * 



