INDEX TO GEOLOGY OF THE LAKE PLEASANT QUADRANGLE 75 



Mt Rouge, 47; fault, 55 



Mount Rouge-Dunham ridge, 8 



Mud lake mountain fault, 52 



Newland, D. H., cited. 9, 33 

 Ninemile creek, fault, s:^, 55 ; gabbro, 

 29; granite, 25; syenite, 19; till, 66 

 North Branch-Moose mountain fault, 



53 

 Xorthville Paleozoic area. ^2 

 Notch, the, fault. 46; Grenville series, 



10 



Oak Hill fault. 50 



Orthoceras hudsonicum, 41 cf. jun- 



ceum, 39 

 Oxbow lake, 70 

 Oxbow mountain fault, 50 



Pachydictya acuta, 39 



Paleozoic history, 57-59; rock out- 

 liers, 8, 32-45 



Panther mountain fault, 51 



Pegmatite dikes, 72 



Phytopsis tubulosum, ^7 



Pine lake fault, 53 



Pine mountain fault, S3 



Piseco lake. 7, 70; fault, 51 



Plectambonites sericeus. 39, 41 



Porphyries, granite and syenite, 25- 

 26 



Potash mountain fault, 52 



Potsdam sandstone. 8, 33, 34, 41, 42, 

 44. 58 



Precambric history, 57 ; rocks. 9-32 



Primitiella unicornis. 41 



Quartzites, 10 



Refinesquina alternata. 39. 41 



deltoidea. 39 

 Rhynchotrema inequivalve, 39 

 Road metal, 71 

 Rock lake, 54 

 Ruedemann, R., cited, 9, 33, 37, 39 



Sacandaga lake, 7, 69; drainage, 63; 



fault, 50; Grenville series, 12 

 Sacandaga river, 7 ; drainage, 61 ; 



fault, 53, 55; granite porphyry, 26; 



mixed gneiss, 27 



Sand lake, syenite, 17 



Silver Lake mountain, fault. 53; 

 Grenville series, 10 



Silver lake outlet fault, 53 



Smyth, C. H., cited, 17 



Southerland mountain fault, 48 



Speculator-Hamilton mountain fault, 

 49 



Speculator-Lookout mountain area, 

 syenite, 18 



Speculator mountain, 8; fault, 55; 

 syenite, 17 



Speculator village fault, 51 



Stone quarries, 71-72 



Streptelasma corniculum, 39 



Sugarloaf-Silver Lake mountain 

 fault, 53 



Swart mountain fault, 52 



Syenite, 14-23; basic phases, 17; ex- 

 amples of, 16; granitic, 20 



Syenite-granite series, 8 



Syenite porphyries, 25-26 



Tetradium tubulosum, 43 



Theresa transition beds, 8, 33, 35, 



41, 42, 44, 58 

 Three ponds, 70 

 Three Ponds-Blue Ridge mountain 



mass, 8 

 Three Ponds mountain, fault, 54, 55; 



Grenville series, 10 

 Till. 66 



Trenton limestone. 8, 33, 38, 72 

 Tribes Hill limestone, 36 



Wallace mountain, Grenville series. 

 10 



Wells, 7, 8; Canajoharie black shale, 

 45 ; outlier at, 32 ; outlier faults, 46 



Wells lake, 67 



West branch Sacandaga river, dia- 

 base, 31; drainage, 61; gorge o-f, 

 70-71 



West Hill, granite, 25 ; Grenville se- 

 ries, 13; mixed gneiss, 27 



Whitehouse, fault, 52, S3; syenite. 23 



Whitehouse lake, 68 



Whitman mountain, fault, 54 ; gran- 

 ite porphyry, 26 



Willis mountain fault, 52 



