INDEX. 



525 



Chert l>rpcci:i, 13ft. 1 40. 391. 394, 395. 462. 



aescribed. 157. 169, 403. 406-407. 

 Chert concretions. 205. 

 Chert conglomerate, 139, 391, 454. 



described. 167, 169, 482. 

 Chert-schist, 225. 



described. 226. 245. 



(See Chcrty limcstoin', Ferrutjinntis chi^ff. Flint, Hnna- 

 tidc chert, Jasper, Li tnestone, SUico, Qiifirtz.) 

 Cherty carbonate. (See Iron carbonate.) 

 Cherty iron rarbnuate. (See Iron carbonate.) 

 Cherty limi-stoue, 3. 127-142. 24S. 429. 433. 435. 438, 443-444, 449, 

 451. 452, 457. 464, 467. 469, 471, 472-473, 474. 



fragments of, 423. 



relations to Eastern iirea rocks, 422, 423, 



relations to gneiss. 446. 



relations to granite, 127-128, 415. 



relations to Quartx-slate, 130, 134. 139. 141. 142. 143. 144. 147, 

 171,180.181,443,454.464. 



relations to schist, 127-128, 446. 



relations to slate, 128, 134, 139, 445. 



thickness of, 130, 141. 



unconformably below Penokee series proper, 454-455. 



unconformable above Southern Complex, 444-454. 

 {See Chert, Li)ne,':toin'.) 

 Chippewa valley district, 1, 460, 472,473. 

 Chlorite, alteration of, 353. 



from iictiuolitr. 210. 2i:^214. 



from augite, 356,414, 415, 417. 



from feldspar. 118, 122, 151. 17it, 180, 333-336,353,413,414, 

 415,418. 



from hornblende, 122. 



from phigiorliKse, 115,417. 



from pyroxene, 115. 



of actinolitic slate, 196. 210, 213, 364. 



of augite-porphyrite, 415. 



of cherl, 134. 

 ' of day-slate, 305. 



of con^jlomerate, 448. 



of diabase, 356. 359. 



of ferruginous chert, 203. 



of forrugiuoiis .•*late, 203. 



of gneiss. 108-lo:i, 111, 116. 118. 119, 120. 



oCgranite, 106, 107, 112, 122. 123. 



of gray wacke, 307. 333. 334. 335. 336. 



of greenstone conglomerate, 375, 376, 377. 



of iron carbonate 190.200. 



of mica-schist, 307, 308, 309. 



of mica-slate. 307, 308. 309. 



of microgranite, 112. 



of porphyrite, 418. 



of quartzite, 153-1-54. 



of Quartz-slate. 148. 151, 152. 468. 



of schist, 121. 



of slate, 364.365,370. 



of syenite, 122. 



of Upper slate, 303. 



of veins, 202. 418. 



relations (o hornblende, 119. 

 Chlorite amygdules, 418. 

 Chlorite-gueiss, 108, 116. 

 Chlorite rock. 111. 

 Chlorite-schist. 308, 309. 

 Chlorite slaje. described. 382. 384, .391. 486. 



Eastern area, 369, .391. 

 Claiborne iron carbonate, 247. 

 Clay shale, 147, 149, 170. 



Clay-slate. 147, 302, 303, 304. 344, .363, 365, 389, 391. 465. 469. 



analysis of, 306. 



cleavage of, 434. 



described, 305-306, 327-328. 330, 331 , 372, 398, 399, 400. 



dip of, 434. 



relations to gray wackes, 305, 333. 



relations to greenstone-conglomerate, 374, 375. 



relations to iron ore, 285, 286. 

 (See .S7rt^t!, I'hi/Uifc.) 

 Cleavage of actiuolitic slate. 195, ^ 



Ch^avage of slate, 296. 390. 426, 427, 434. 

 Coli)y mine, 164, 232, 269, 270. 273. 281. 355, 510. 

 Concentration of iron oxide, 2.54. ^ 



(.'miceutration of silica. 255. 

 Concretions, 205-209, 268. 



of actinolitic slate, 212. 2.58. 266. 267. 



of ferruginous chert. 212. 254. 255. 257. 265. 

 Cnnglomerate, 147. 148, 302, 303, 304-:(0.5. 364,393,394.395.454. 

 455. 



basal, 172, 173, 174, 180, 181, 388, 391. 443. 447-451. 4.57. 461- 

 462,464,471,472. 



basal, relations to Southern Complex. 422. 



described, 159. 161. 164-165, 326, 371, 400. 401. 409, 482. 

 (See Jas2}er'Confjloinrratr. Chert-cojiglomcrate.) 

 Con glomerate, slate, uiicouformably above schist, 147. 

 Conover referred to, 9 10. 44. 

 Copper-bearing series, 47, 48, 66-67. 



relations to granite, 104. 

 (See Kewecttawan.) 

 Coiitchieliing, 473. 

 Credner referred to, 56. 

 Cretaceous chert, 252. 

 Crystalline roi-ks of AViscon.sin. 41. 

 Crystallizatir)n of granite. 113. 



of microgranite. 112-113. 



of syenite. 114. 

 Currant river, 469. 



I). 

 Dakota, 473. 474. 

 Dawson's road, 498. 



Decomposition of rocks, etfect of environment on, 358. 359. 

 Devonian, 86. 

 Diabase, 103, 115, 122, 261,268,346,347,425,431,435,465.466. 



alteration of, 348. 355, 356, 357, 358, 359. 



analysis of, 357. 



description of. 348, 3.54. 410-414. 



grades into gablmi, 348. 350, 358, 410. 



of Ktnveenawan. .52, 349, 377. 



of Southern Complex. 349,358. 



ophitic struct ure of, 350. 351, 410. 



relations to augitc-porphyrite, 41.5. 



relations to grccnslon<> conglomerate nr«!a,410. 

 Diabase-porphyrite. <lescribed. 416,417. 



of Keweenawan, 377. 

 Dial compass. VTriirbl on. 52. 

 Dialbge. alteration of, 115, 353. 



of gabbro, 11.5,350. 353. 

 Dikes. 346. 347, 348. 358. 359. 



alteration of, 255. 271, 290. 



dip of 279. 



of iron tormation, 3,55-358.3.59. 



of Soullu-rn Complex. 3'49. 



of Cpper slate. 358. 



pitch of 27S, 



relations lo Iron-bearing member. 12. 271-274. 465, 466, 



relations to Keweenawan, 465. 



