442 



INDEX 



Splint coal, 71 



Spotted slate, 76 



Springs, in bedded rocks, 350 ; in 

 igneous rocks and schists, 353 ; shal- 

 low and deep-seated, 355 ; use of, in 

 field geology, 287 



Sprudelstein, 70 



Stackpolly, 406 



Stalactites, 64 



Stalagmites, 64 



Staurolite, 26 



Steatite, 23 



Step-faults, 167 



Steppes, 412 ; fauna of, 392 



Stilbite, 26 



Stockworks, 252, 260 



Stone coal, 71 



Stoss-seite, 314 



Strata, thinning and thickening of, 112, 

 293 ; grouping of, 113 ; contempor- 

 aneity of strongly contrasted, 1 14 



Stratification, 107, 109, 115 



Stratified rocks, 55 



Stratum, 108 



Streaky structure, 80 



Striae, glacial, 313 



Strike, 132 ; -faults, 162 ; -joints, 146 



Structural geology, 104 ; economic 

 aspects of, 330, 347 



Subaerial rocks, 56 



Subhedral (hypidiomorphic) minerals, 

 36 



Subsequent eruptive rocks, 184 



Subsequent mountains, 405 



Subsequent valleys, 415 



Subsoil, 57, 282, 368, 376 



Substitution pseudomorphs, 38 



Succession of minerals in lodes, 249 



Sulphates, 29 



Sulphide ores, 231 



Sulphides, 27 



Sun-cracks, 118 



Superficial accumulations, 307 



Superior, Lake, 419 



Surface-creep, 129 



Surface-markings, 116 



Surface-wash, 308 



Sweden, ores of, 229, 234 



Syenite, 46, 89 



Syenitic mica-trap, 46 



Symmetrical folds, 135 

 Symmetrical lodes, 246, 397 

 Synclinal valleys, 352, 413 

 Synclines, 136 

 Synclinorium, 140 

 Syngenetic ores, 228 

 Systems of lodes, 241 



Tablelands, 412 



Tachylite, 51 



Talc, 23 ; -schist, 78, 88 



Tar springs, 72 



Tectonic basins, 419, 422 



Tectonic geology, 104 



Tectonic mountains, 394, 403, 407 



Tectonic valleys, 41 3 



Temperature, underground, 106, 145, 



270 

 Terminal curvature, 129 

 Terra rossa, 58, 385 

 Terrestrial movements, evidence of, 102 

 Tertiary deposits, 307 

 Thermal metamorphism, 214, 219 

 Thickening and thinning of strata, 1 12, 



293 



Throw of faults, 156 



Thrust-planes, 174 



Till. See Boulder-clay 



Tin-ore veins, 218 



Titanite, 25 



Toadstones, 269 



Tonalite, 48 



Topaz, 249 



Torrent-track of rivers, 417 



Torridon Mountains, 406 



Torso mountains, 407, 415 



Tourmaline, 25 ; -granite, 42 ; -hornfels, 



79 



Trachyte, 47, 86, 87, 89 

 Transcurrent faults, 170 

 Transported soils, 376 

 Transvaal, gold of, 261 

 Transverse lodes, 240 

 Transverse thrusts, 170, 175 

 Travelled soils, 376 

 Travertine, 65 

 Trees in peat, 319 

 Tremolite, 16 

 Troctolite, 49 

 Trough-faults, 167 



