470 



INDEX 



Fractures, zone of, 78. 

 Fragmental rocks, 39. 

 Fringing reef, 259. 

 Fungi, 293. 

 Fusulina limestone, 382. 



Gabbro, 29, 82. 



Gastropods, 298, 337, 345, 354 



423. 



Generalized type, 393, 443. 

 Geodes, 122. 

 Geologic divisions, 306. 

 Geologic processes, 10. 

 Geology, 9. 

 Geysers, 113. 



Glacial conditions in tropics, 394. 

 Glacial trough, 221. 

 Glaciated hills, 219. 

 Glaciation, effects of, 456. 

 Glaciers, 191-230. 

 Glass, volcanic, 31. 

 Glassy rocks, 26. 

 Glauconite, 258. 

 Globigerina ooze, 258. 

 Gneiss, 18, 42, 43. 

 Gold, 120, 437. 

 Goniatites, 365, 373. 

 Gorges, 162. 

 Gradation, 11. 

 Grade, 135. 

 Gradient, 134. 

 Granite, 23, 28. 

 Granite rocks, 130. 

 Granitoids, 25. 

 Graptolites, 296, 344. 

 Great Plains, 419, 421. 

 Great Salt Lake, 356. 

 Greensand, 258. 

 Ground water, 107. 

 Gully, 138. 

 Gymnosperms, 294. 

 Gypsum, 22. 



Hamilton shales, 360. 

 Hanging valley, 222, 225. 

 Hardpan, 209. 

 Helderberg limestone, 359. 

 Hematite, 22, 350. 



Hesperornis, 427. 

 Hills, glaciated, 219. 

 Hogbacks, 166, 432. 

 Hook, 247. 

 Horizons, 331. 

 Horizontal fault, 74. 

 Hornblende, 21. 

 Huronian system, 323. 

 Hydration, 104. 

 Hydroids, 296. 

 Hydrosphere, 14, 15, 109. 



Ice cap, 194, 449. 

 Ice field, 191. 

 Ice pillars, 200. 

 Ice sheet, 194. 



Greenland, 203. 



latest, 455. 



south polar, 202. 

 Ice sheets, effect of, 450-452. 

 Ichthyosaur, 401. 

 Igneous rocks, 23, 37, 46, 49. 

 Incompetent folds, 68. 

 Incompetent strata, 67. 

 Inlet, 250. 

 Interior sea, 351. 

 Intermediate rocks, 24. 

 Intermittent streams, 139. 

 Intrenched meanders, 152. 

 Intrusion, laccolithic, 51. 

 Inundations, Cretaceous, 419. 

 Invertebrates, Triassic, 399. 

 Iron, 120, 323. 

 Island, chimney, 244. 



land-tied, 248. 

 Islands, barrier, 248. 



Jellyfish, 296. 

 Joints, 53, 70, 71. 

 Jurassic period, 405-411. 



Kame, 228, 455. 

 Kaolin, 22. 



Karst topography, 118. 

 Keweenawan system, 324. 



Laccolithic intrusion, 51. 

 Laccoliths, 50. 

 Lagoon, 250. 



