﻿INDEX TO GEOLOGY OF THOUSAND ISLANDS REGION 



191 



Great Bend, 143. 



Grenville limestones, 28, 56, 57, 132; 



resting on an ancient lava flow, 25 ; 



Potsdam contact on, 58; use for 



road metal, 173. 

 Grenville quartzites, 12, 31. 

 Grenville rocks, 8, 24, 26-36, 45 ; of 



Keewatin age, 25; foliation in, 



100-1 ; folds, 108-9. 

 Grenville schists, 12, 34-36, 47, 172; 



Potsdam contact on, 58. 

 Grindstone island, granite, 11, 41, 43, 



50, 174; conglomerates, 15; quartz- 



ite, 26, 31, 112; dikes, 44; Potsdam 



sandstone, 62; boulder kames, 153. 

 Grindstone quadrangle, 5, 6. 

 Guffin bay, 89, 115. 



Hall, cited, 79. 

 Hammond, 174. 

 Helicotoma, 72. 

 Hematite, 49, 50, 172, 181. 

 Hillebrand, Dr W. F., quoted, 178- 



79, 180. 

 Hinds, F. A., cited, 143. 

 Hormoceras tenuifilum, 84, 87, 90. 

 Hornblende, 33, 34, 35, 38, 39, 40, 41, 



44, 5i, 52, 53, 119, 181, 183, 184. 

 Horse creek, 81. 

 Howe Island, 67. 

 Hoyt limestone, 97. 

 Hyde creek-Perch river valley, 127. 

 Hyde lake, 127, 132. 

 Hypersthene, 44. 



Igneous rocks, 9-13, 24, 36-38; later 



foliation of, 102-3. 

 Illaenus americanus, 90. 

 Ilmenite, 181. 



Indian river, 7, 26, 56, 127, 128. 

 Inliers, 114. 



Iron ore, 35. See also Hematite. 

 Iroquois, Lake, 137-38. 

 Iroquois plane, altitude, 139. 

 Isle La Motte marble, 79. 

 Isochilina, 72. 

 Isotelus platycephalus, 90. 



Joints, 103-8. 



Kames, 153, 154-55- 



Keewatin formation, 25. 



Keuka valley, 166. 



Kingston, 6, 67, 77 \ granite, 41. 



Klock's quarry, 85. 



Knight, cited, 25. 



Labradorite, 44, 49. 



Lafargeville, 151, 153, 155- 



Lake basins, 148-50. 



Lake Iroquois, 137-38. 



Lakes, 131-33- 



Laurentian granite, 36-38; quarries, 



174. 

 Laurentian granite gneiss, 10, 12, 51 ; 



use for road metal, 173; analyses, 



176, 185. 

 Leperditia, 72. 



fabulites, 83, 90. 

 Leray limestone, 18, 79, 80, 82, 84-90, 



95, 96, 97, 98, 114, 115, 130, 133, 



134, 135, 136. 

 Leray sville moraine, 160. 

 Limerick, 89, 134, 135. 

 Limestone flutings, 164. 

 Limestone ribbing, 167-69. 

 Limestones, 28-31, 55; quarries, 175. 

 Lingulepis acuminata, 63, 65, 66. 

 Little Falls dolomite, 65, 66, 97. 

 Lituites undatus, 84, 88. 

 Long Lake gneiss, 38. 

 Loon Lake syenite, analysis, 182. 

 Lophospira, 72. 



perangulata, 72. 

 Lorraine shale, 19, 54, 123, 124. 

 Lowville, 77. 

 Lowville limestones, 6, 18-20, 54, 79, 



80-84, 85, 89, 95, 96, 97, 114, 115, 



130, 132, 133, 134, 136; fold, 115, 



116; quarries, 173, 174, 175. 



Magnetite, 33, 36, 38, 40, 44, 49, 64, 



177, 178, 183. 

 Martinsburg, 70, 77. 

 Mather, cited, 79. 

 Medina sandstone, 19. 

 Medina shale, 123. 



Mica, 29, 32, 36, 40, 50, 52, 64, 119. 

 Microcline, 36, 40,- 41, 49, 181, 183, 

 184. 



