﻿78 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Thus 
  it 
  is 
  more 
  than 
  probable 
  that 
  northern 
  New 
  York 
  under- 
  

   went 
  erosion 
  during 
  all 
  of 
  the 
  late 
  Paleozoic 
  era 
  and 
  certainly 
  

   during 
  the 
  Mesozoic 
  era, 
  when 
  an 
  immense 
  amount 
  of 
  Paleozoic 
  

   sediment 
  and 
  some 
  Precambric 
  rock 
  were 
  stripped 
  off 
  by 
  erosion. 
  

   By 
  the 
  close 
  of 
  the 
  Mesozoic 
  northern 
  New 
  York 
  was 
  reduced 
  

   to 
  the 
  condition 
  of 
  a 
  fairly 
  good 
  peneplain 
  with 
  some 
  hard 
  rock 
  

   masses 
  rising 
  to 
  moderate 
  heights 
  above 
  the 
  general 
  level. 
  

  

  At 
  the 
  close 
  of 
  the 
  Mesozoic, 
  or 
  the 
  beginning 
  of 
  the 
  Cenozoic 
  

   era, 
  the 
  great 
  peneplain 
  was 
  upraised 
  and 
  a 
  new 
  period 
  of 
  active 
  

   erosion 
  was 
  inaugurated 
  to 
  continue 
  to 
  the 
  present 
  time. 
  

  

  Much 
  of 
  the 
  faulting 
  of 
  the 
  area 
  dates 
  from 
  the 
  time 
  of 
  this 
  

   peneplain 
  uplift 
  or 
  even 
  later, 
  though 
  it 
  is 
  likely 
  that 
  some 
  dates 
  

   from 
  toward 
  the 
  close 
  of 
  the 
  Paleozoic 
  era 
  at 
  the 
  time 
  of 
  the 
  great 
  

   Appalachian 
  revolution. 
  

  

  Immediately 
  preceding 
  and 
  probably 
  during 
  much 
  of 
  the 
  great 
  

   Ice 
  age 
  this 
  region, 
  like 
  all 
  the 
  northeastern 
  United 
  States, 
  was 
  

   considerably 
  higher 
  than 
  now 
  as 
  proved 
  by 
  such 
  drowned 
  river 
  

   channels 
  as 
  those 
  of 
  the 
  lower 
  Hudson 
  and 
  St 
  Lawrence. 
  

  

  During 
  the 
  Ice 
  age 
  of 
  the 
  Quaternary 
  period, 
  the 
  area 
  of 
  the 
  

   quadrangle, 
  in 
  common 
  with 
  all 
  New 
  York 
  State, 
  was 
  buried 
  under 
  

   a 
  great 
  ice 
  sheet 
  which 
  has 
  left 
  many 
  records 
  such 
  as 
  striae, 
  glacial 
  

   boulders, 
  moraines, 
  and 
  drift 
  deposits 
  in 
  general. 
  The 
  preglacial 
  

   topography 
  was 
  not 
  profoundly 
  altered 
  by 
  ice 
  erosion 
  and 
  deposi- 
  

   tion. 
  The 
  many 
  extinct 
  and 
  existing 
  lakes 
  of 
  the 
  quadrangle 
  were 
  

   formed 
  either 
  by 
  the 
  actual 
  presence 
  of 
  the 
  ice 
  dam 
  itself 
  or, 
  more 
  

   commonly, 
  by 
  irregular 
  deposits 
  of 
  drift 
  across 
  old 
  stream 
  channels. 
  

  

  A 
  subsidence 
  of 
  the 
  land 
  several 
  hundred 
  feet 
  below 
  the 
  present 
  

   level 
  took 
  place 
  toward 
  the 
  closing 
  stages 
  of 
  the 
  Ice 
  age 
  or 
  im- 
  

   mediately 
  after 
  it 
  for 
  this 
  latitude, 
  when 
  arms 
  of 
  the 
  sea 
  extended 
  

   through 
  the 
  Champlain 
  and 
  St 
  Lawrence 
  valleys. 
  

  

  The 
  most 
  recent 
  movement 
  of 
  the 
  land 
  has 
  been 
  a 
  differential 
  

   uplift 
  with 
  greater 
  elevation 
  toward 
  the 
  north. 
  At 
  the 
  latitude 
  of 
  

   the 
  North 
  Creek 
  sheet, 
  this 
  postglacial 
  uplift 
  has 
  amounted 
  to 
  a 
  

   few 
  hundred 
  feet, 
  the 
  differential 
  character 
  of 
  the 
  uplift 
  being 
  

   shown 
  by 
  the 
  tilting 
  of 
  certain 
  of 
  the 
  extinct 
  glacial 
  lake 
  deposits. 
  

  

  ECONOMIC 
  GEOLOGY 
  

  

  GARNET 
  

  

  At 
  the 
  time 
  of 
  the 
  field 
  work 
  but 
  one 
  garnet 
  mine 
  was 
  in 
  actual 
  

   operation 
  within 
  the 
  map 
  limits, 
  but 
  in 
  all 
  there 
  are 
  at 
  least 
  five 
  

   localities 
  where 
  more 
  or 
  less 
  garnet 
  mining 
  has 
  been 
  carried 
  on 
  

   as 
  follows: 
  (1) 
  near 
  the 
  top 
  of 
  Oven 
  mountain; 
  (2) 
  one-half 
  

  

  