INDEX. 



511 



Town. 45 N., R. 33 W., section 9 157 



section 15 149 



section 16 149, 157 



section 20 158, 175, 176 



section 22 149 



section 27 149 



section 34 153 



46 N.,K. 30 W., section 19 453 



section 46 406 



46N., R.Sl'W' 13,38,427 



46N.,E.31 W.,section 32 447 



46N.,R.32'W" 38,148,155,156,427 



46 N.,K. 32 W., section 16 149 



section 21 128,334 



section 31 149 



section 36 73, 149 



46N.,R.33 W 156 



46 N.,E. 33 W., section 24 147,149,199 



section 27 204 



section 34 149,156,163,175,176 



47N.,R.30 W 329,457 



47N.,R.30 W.,section9 334 



section 19 333 



section 30 333 



47N.,R.31"W 13,329,332 



47 N.,R. 31 "V^., section 24 333 



section 25 333 



section 36 333 



47 N.,R. 33 "W., section 19 199,204 



48N.,R.31'W 13 



Tracliy tic texture in pyroclastics 147 



Tremolite developed by dynamic action 432 



from olivine 217 



included in chlorite 218 



of dolomite 408,410,436 



of picrite-porphyry 214,218 



{See Amphibole.) 



Trout Lake 335 



Tuff, basalt, perlitic parting in, plate of 294 



breccia, use of term 137 



conglomerate, use of term 137 



of Hemlock formation 64, 76 



described 137-143 



thickness of 141 



origin of ]41-^142 



palagonite, use of term 138 



relations to ash beds 143 



resemblance to Tertiary and Recent tuffs 142 



use of term 136 



Tuffogene sediments described 143-145 



Turner, H. TV., on granodiorite 231 



Twinning of feldspar. ... 42, 104, 191, 201, 224, 228, 233, 261, 468 



of muscovite 197 



of pyroxene 250 



of rutile 56, 205, 236 



U. 

 Ultrabasic intrusives in Crystal Falls district 



described 212-221 



in Upper Huronian 164 



Unconformity. (See Relations iinder particular 



formations and series.) 

 Undulatory extinction in quartz (see Pressure 



effects) 41, 81, 82, 90, 133, 169, 225, 388, 464, 477 



Union mine. {See Columbia mine.) 



United States Land Survey 343 



United States surveyors on Sturgeon River tongue. 450-460 



United States Geological Survey, topography by 22 



Upper Cambrian. (See Potsdam, Lake Superior 

 sandstone.) 



Upper Huronian described xviii, xxi, 27, 155-186, 423-426 



correlation of 155, 164, 165 



distribution of 155, 156 



folding of 158-162,188 



sketch of 179 



relations to intrusives 189-190 



intrusives in 174,175,187 



magnetic observations in 156,157,339 



metamorphism of 28,425,420 



of Felch Mountain range described 423-426 



of Penokee series xxi 



ore deposits of 28 



described 175-186 



table of shipments of Op. 186 



relations to Archean xxi 



relations to basic intrusives 204, 211, 223 



relations to Cambrian sandstone *. 155,161,162 



relations to grit 155 



relations to Groveland formation xxi, 425 



relations to Hemlock formation 77 



relations to intrusives 164,190,204.211,223 



relations to ilansfield formation xxii 



relations to Michigamme formation 28, 165 



relations to Lower Huronian xvii 



XXII, 158, 160, 161, 162, 163, 176, 424 



relations to Randville dolomite 424 



relations to Sturgeon quartzite xxii 



relations to Upper Marquette 155 



succession in xxv, xxvi 



thickness of 157 



topography of 155, 156 



Upper Marquette, correlation of xxv, xxvi 



iron-bearing series referred to 20 



iron ore deposits, comparison with Crystal Falls 



iron ore deposits 180,181 



relations to Upper Huronian 155 



Uralitefrom augite 104,201,212 



from pyroxene 48 



including feldspar 202 



of metadolerite 200 



of volcanic conglomerate 144 



V. 

 Van Hise, C. R., connection with Lake Superior Sur- 

 vey 21,22 



indebtedness to 12 



on alteration of siderite 168 



on concretionary structure in ferruginous chert- 422 



on correlation of Crystal Falls ore deposits 20 



on Felch Mountain range 380 



on formation of crystalline schists 172 



on Lake Superior stratigraphy 19 



on Mesnard area 452, 457 



on metamorphism of basic rocks 152 



on mica-schist 414 



on Michigamme formation 165 



on ore concentration 72 



on ore deposits of Armenia mine 183 



on ore deposits of Hemlock mine 177 



on origin of siderite 168 



on origin of iron ore 39. 70, 71, 130, 168 



on sericite-schist from recomposed granite 52 



