﻿Education 
  Department 
  Bulletin 
  

  

  Published 
  fortnightly 
  by 
  the 
  University 
  of 
  the 
  State 
  of 
  New 
  York 
  

  

  Entered 
  as 
  second-class 
  matter 
  June 
  24, 
  1908, 
  at 
  the 
  Post 
  Office 
  at 
  Albany, 
  N. 
  Y., 
  

   under 
  the 
  act 
  of 
  July 
  16, 
  1894 
  

  

  No. 
  485 
  

  

  ALBANY, 
  N. 
  Y. 
  

  

  December 
  15, 
  1910 
  

  

  New 
  York 
  State 
  Museum 
  

  

  John 
  M. 
  Clarke, 
  Director 
  

   Museum 
  Bulletin 
  145 
  

  

  GEOLOGY 
  OF 
  THE 
  THOUSAND 
  ISLANDS 
  REGION 
  

  

  ALEXANDRIA 
  BAY, 
  CAPE 
  VINCENT, 
  CLAYTON, 
  GRIND- 
  

   STONE 
  AND 
  THERESA 
  QUADRANGLES 
  

  

  BY 
  

  

  H. 
  P. 
  GUSHING, 
  H. 
  L. 
  FAIRCHILD, 
  R. 
  RUEDEMANN 
  AND 
  

   C. 
  H. 
  SMYTH 
  JR 
  

  

  Introduction 
  5 
  

  

  Location 
  and 
  character 
  6 
  

  

  Summary 
  of 
  geologic 
  history. 
  . 
  . 
  8 
  

  

  Igneous 
  intrusions 
  9 
  

  

  Close 
  of 
  the 
  long 
  period 
  of 
  

  

  erosion 
  14 
  

  

  Paleozoic 
  sediments 
  14 
  

  

  Subsequent 
  history 
  of 
  the 
  

  

  region 
  20 
  

  

  The 
  Pleistocene 
  23 
  

  

  The 
  rocks 
  24 
  

  

  Precambric 
  rocks 
  24 
  

  

  Great 
  Precambric 
  erosion. 
  ... 
  53 
  

  

  Paleozoic 
  rocks 
  54 
  

  

  Precambric 
  surface 
  under- 
  

   neath 
  the 
  Potsdam 
  54 
  

  

  Potsdam 
  sandstone 
  60 
  

  

  Theresa 
  and 
  Tribes 
  Hill 
  forma- 
  

   tions 
  64 
  

  

  Pamelia 
  formation 
  68 
  

  

  Mohawkian 
  series 
  79 
  

  

  Summary 
  of 
  Paleozoic 
  oscilla- 
  

   tions 
  of 
  level 
  92 
  

  

  Dip 
  of 
  the 
  Paleozoic 
  rocks. 
  . 
  . 
  98 
  

  

  Rock 
  structures 
  99 
  

  

  FoHation 
  99 
  

  

  Joints 
  103 
  

  

  Folds 
  108 
  

  

  Faults 
  118 
  

  

  Topography 
  . 
  121 
  

  

  PAGE 
  

  

  Paleozoic 
  altitude 
  and 
  climate 
  122 
  

  

  Amount 
  of 
  erosion 
  123 
  

  

  Original 
  drainage 
  . 
  124 
  

  

  Tertiary 
  uplift 
  125 
  

  

  Tertiary 
  drainage 
  125 
  

  

  Plateaus, 
  terraces, 
  scarps. 
  ... 
  129 
  

  

  Lakes 
  131 
  

  

  Undergroulid 
  drainage 
  133 
  

  

  Pleistocene 
  geology 
  136 
  

  

  History 
  . 
  . 
  136 
  

  

  Physiography 
  141 
  

  

  Glacial 
  deposits 
  150 
  

  

  Glacio-aqueous 
  deposits 
  156 
  

  

  Glacial 
  erosion 
  159 
  

  

  Prewisconsin 
  glaciation 
  164 
  

  

  Economic 
  geology 
  172 
  

  

  Road 
  metal 
  173 
  

  

  Granite 
  quarries 
  174 
  

  

  Sandstone 
  quarries 
  1 
  74 
  

  

  Limestone 
  quarries 
  175 
  

  

  Petrography 
  of 
  some 
  PrecarnbriQ 
  " 
  

  

  rocks 
  .,. 
  .'>... 
  1 
  75 
  

  

  Bleached 
  granite 
  (. 
  'Jj-k'l 
  - 
  y 
  

  

  Picton 
  granite 
  \. 
  . 
  . 
  . 
  T 
  I'Si 
  -"■ 
  - 
  

  

  Alexandria 
  S3^enite 
  ■. 
  . 
  . 
  . 
  182 
  j? 
  1 
  r 
  

  

  Granitized 
  amphibolite 
  and"' 
  -^ 
  • 
  O 
  

   amphibolitized 
  granite 
  

   (soaked 
  rocks) 
  184 
  

  

  Index 
  180 
  

  

  M222r-09-2000 
  

  

  ALBANY 
  

  

  UNIVERSITY 
  OF 
  THE 
  STATE 
  OF 
  NEW 
  YORK 
  

   I910 
  

  

  