:5o 



NEW YORK STATE MUSEUM 



Fishkill creek, 12 



Folds, 80 



Fordham gneiss, 20 



Formation groups of larger petro- 

 graphic significance, 45 



Fort Montgomery, 7 



Foundry brook, 12, 89 



Foundry brook section, Catskill aque- 

 duct, 99 



Garrison, 7, 12 



Garrison tunnel, 13 ; Catskill aque- 

 duct, lOI 



Geography of quadrangle, ^ 



Geologic formations, 22 



Geology, general, 16 



Glacial history, 118 



Glacial modification, 145 



Glacial unconformity, 75 



Gneisses, mixed, petrogenesis, 6; 

 hornblende gneisses associated with 

 magnetite veins, 16; structural con- 

 ceptions, 19; general strike, 22; 

 hornblende-jplagioclase, 57 ; in- 

 jection, 59; impregnation, 59; men- 

 tioned, 22, 23, 27, 119 



Gordon, C. E., cited, 20, 21 



Granite, 19, 22, 23, 2.'/, 119; building 

 stone, 82 



Graphite, 91 



Gravel, 88 



Graywackes, 46, 63 



Grenville metamorphism, 106 



Grenville sedimentation, 105 



Grenville series, 26, 29, 31, 32, 2)Z': 47> 

 49 



Haverstraw, 89 



Herbert, Edres, 91 



Highland belt, 10 



Highland Falls, 7, 12 



Highlands, 7; Mather's description 



of structural features, 17 

 Highlands-Adirondack correlation, 



summary of, 125 

 Highlands gneiss, 22 

 Historical geology, 105 

 Hornblende-norite, 67 

 Hudson, Henry, 14 



Hudson river, extraordinary features, 

 10; exact depth of gorge, 11; depth 

 as ascertained by work on Catskill 

 aqueduct, 94-97 



Hudson River crossing from Storm 

 King to Breakneck mountain, 

 Catskill aqueduct, 93 



Hudson river formation, 46; descrip- 

 tion, 63 



Hudson river phyllite, 43 



Hudson river series, 22, 23, 31, j^z, 129 



Hudson river shales, 23 



Hudson river slates, 21 



Hudson River-Wappinger series, 84 



Hudson schist, 20 



Hudson trench, through the High- 

 lands, 10 



Igneous history, Post-Grenville vol- 

 canism, 108 



Igneous impregnation, 40 



Igneous injection, 39 



Igneous invasion, 122 



Igneous rocks, 27, 48, 51, 64 



Interstate Park, 7 



Inwood limestone, 20, 22, 23, 85 ; de- 

 scription, 62 



Inwood series, 23, 31, 32, 33, 47, 120 



Iron, 87 



Islands, 10 



Jones point, 88 



Kemp, James F., cited, 20, 21, 120 

 Keweenawan, 123 

 Kings quarry, 52 

 Kingston, 14 



Lime, 86 



Limestone, building stone, 84 

 Limestones, structural conceptions, 

 19; mentioned, 18, 22, 23, 27, 46, 



47 

 Location map, 8 

 Lorillard, Mr, 92 

 Losee gneiss, 19 

 Lowerre quartzite, 20, 60 

 Lowerre series, 23, 31, 47, 129 



