﻿GEOLOGY 
  OF 
  THE 
  NORTH 
  CREEK 
  QUADRANGLE 
  6$ 
  

  

  feature 
  probably 
  even 
  more 
  prominent. 
  The 
  comparatively 
  even 
  sky 
  

   line 
  of 
  the 
  western 
  Adirondacks 
  together 
  with 
  the 
  high 
  plateau 
  

   called 
  Tug 
  Hill 
  just 
  west 
  of 
  the 
  Black 
  River 
  valley, 
  practically 
  

   prove 
  the 
  former 
  peneplain 
  condition 
  of 
  that 
  portion 
  of 
  the 
  

   Adirondacks. 
  This 
  peneplain 
  is 
  known 
  to 
  have 
  been 
  elevated 
  late 
  

   in 
  the 
  Cretacic 
  period 
  or 
  the 
  early 
  Tertiary 
  period 
  and, 
  as 
  already 
  

   stated, 
  much 
  of 
  the 
  faulting 
  of 
  the 
  eastern 
  Adirondacks 
  occurred 
  

   at 
  the 
  time 
  of 
  that 
  great 
  uplift 
  or 
  even 
  later. 
  Thus 
  the 
  fact 
  that 
  

   this 
  peneplain 
  had 
  considerable 
  irregularities 
  on 
  its 
  surface, 
  com- 
  

   bined 
  with 
  the 
  facts 
  of 
  excessive 
  tilting 
  of 
  the 
  earth 
  blocks 
  by 
  fault- 
  

   ing 
  and 
  subsequent 
  erosion, 
  have 
  quite 
  effectually 
  masked 
  even 
  

   this 
  later 
  peneplain 
  surface. 
  Doctor 
  Ogilvie 
  says 
  with 
  reference 
  

   to 
  the 
  Paradox 
  lake 
  quadrangle, 
  1 
  that 
  the 
  even 
  sky 
  line 
  of 
  some 
  of 
  

   the 
  mountains 
  suggests 
  an 
  uplifted 
  peneplain, 
  and 
  also 
  that 
  the 
  long, 
  

   smooth, 
  eastward 
  slopes 
  of 
  the 
  fault 
  blocks 
  probably 
  represent 
  por- 
  

   tions 
  of 
  the 
  peneplain 
  surface 
  which 
  were 
  produced 
  before 
  the 
  

   faulting. 
  Similar 
  evidences 
  occur 
  within 
  the 
  North 
  Creek 
  quad- 
  

   rangle 
  as, 
  for 
  example, 
  the 
  rather 
  even 
  sky 
  lines 
  of 
  the 
  Henderson, 
  

   Pine-Gage, 
  Huckleberry, 
  and 
  Chase 
  mountain 
  masses, 
  and 
  the 
  

   numerous 
  eastward-sloping 
  fault 
  blocks 
  already 
  described. 
  Any- 
  

   thing 
  like 
  accurate 
  knowledge 
  of 
  the 
  character 
  of 
  this 
  Mesozoic 
  

   peneplain 
  within 
  the 
  map 
  limits 
  is, 
  however, 
  lacking. 
  

  

  GLACIAL 
  AND 
  POSTGLACIAL 
  GEOLOGY 
  

  

  CHANGES 
  OF 
  LEVEL 
  

  

  It 
  is 
  important 
  to 
  recall 
  the 
  well-known 
  fact 
  that 
  the 
  eastern 
  

   portion 
  of 
  North 
  America, 
  including 
  the 
  Adirondack 
  region, 
  im- 
  

   mediately 
  preceding 
  and 
  doubtless 
  during 
  a 
  good 
  part 
  of 
  the 
  Glacial 
  

   epoch 
  was 
  notably 
  higher 
  than 
  it 
  is 
  today. 
  The 
  submerged 
  chan- 
  

   nels 
  of 
  the 
  lower 
  Hudson 
  and 
  St 
  Lawrence 
  rivers 
  prove 
  that 
  the 
  

   land 
  there 
  must 
  have 
  been 
  something 
  more 
  than 
  iooo 
  feet 
  higher 
  

   than 
  now 
  in 
  order 
  to 
  have 
  allowed 
  the 
  channel 
  cutting. 
  Toward 
  

   the 
  closing 
  stages 
  of 
  the 
  Ice 
  age, 
  and 
  directly 
  after 
  it, 
  there 
  was 
  

   a 
  submergence 
  of 
  the 
  whole 
  region 
  to 
  below 
  the 
  present 
  level 
  as 
  

   shown 
  by 
  the 
  so-called 
  raised 
  beaches 
  or 
  delta 
  deposits 
  in 
  the 
  Hud- 
  

   son 
  and 
  Champlain 
  valleys. 
  In 
  the 
  Champlain 
  valley 
  the 
  deposits 
  

   are 
  chiefly 
  clays 
  which 
  were 
  formed 
  in 
  an 
  arm 
  of 
  the 
  sea 
  as 
  proved 
  

   by 
  the 
  presence 
  of 
  marine 
  fossils. 
  These 
  deposits 
  are 
  now 
  several 
  

   hundred 
  feet 
  above 
  sea 
  level 
  in 
  the 
  Champlain 
  valley, 
  which 
  proves 
  

  

  1 
  N. 
  Y. 
  State 
  Mus. 
  Bui. 
  96, 
  p. 
  468. 
  

  

  