﻿GEOLOGY 
  OF 
  THE 
  NORTH 
  CREEK 
  QUADRANGLE 
  63 
  

  

  of 
  feet 
  above 
  the 
  comparatively 
  lowland 
  of 
  the 
  region. 
  A 
  com- 
  

   parison 
  of 
  the 
  North 
  Creek 
  sheet 
  with 
  all 
  other 
  published 
  Adiron- 
  

   dack 
  maps 
  shows 
  that, 
  from 
  the 
  physiographic 
  standpoint, 
  this 
  

   region 
  is 
  noticeably 
  different 
  from 
  the 
  Adirondacks 
  in 
  general. 
  

  

  Some 
  of 
  the 
  best 
  examples 
  of 
  such 
  domes 
  are 
  : 
  Kelm, 
  Chase, 
  

   Tripp, 
  Hackensack, 
  Moon, 
  Heath, 
  Potter, 
  Birch, 
  No. 
  9, 
  Little, 
  

   Crane, 
  Huckleberry, 
  Mill, 
  Stockton, 
  and 
  Prospect 
  mountains. 
  The 
  

   greatest 
  of 
  these 
  domes 
  is 
  Crane 
  mountain 
  which 
  rises 
  2000 
  feet 
  

   above 
  the 
  ' 
  immediately 
  surrounding 
  country. 
  The 
  upper 
  100O 
  to 
  

   1500 
  feet 
  of 
  this 
  mountain 
  are 
  very 
  steep 
  to 
  almost 
  precipitous 
  

   on 
  all 
  sides 
  except 
  the 
  north 
  making 
  this 
  great 
  rock 
  dome 
  a 
  grand 
  

   sight 
  as 
  viewed 
  from 
  Thurman 
  (see 
  plate 
  8). 
  Mill 
  and 
  Stock- 
  

   ton 
  mountains 
  deserve 
  special 
  mention 
  because 
  they 
  rise 
  as 
  two 
  

   great 
  isolated 
  masses 
  above 
  the 
  comparatively 
  low 
  and 
  featureless 
  

   surrounding 
  country 
  and 
  form 
  conspicuous 
  features 
  of 
  the 
  land- 
  

   scape 
  as 
  viewed 
  from 
  any 
  of 
  the 
  higher 
  points 
  for 
  a 
  number 
  of 
  

   miles 
  around 
  (see 
  plate 
  13). 
  As 
  viewed 
  from 
  the 
  south, 
  Potter 
  

   mountain 
  is 
  a 
  fine 
  example 
  of 
  a 
  rock 
  dome 
  which 
  rises 
  700 
  feet 
  

   above 
  the 
  general 
  level 
  of 
  the 
  country 
  (see 
  plate 
  14). 
  

  

  The 
  domes 
  may 
  be 
  classified 
  under 
  three 
  headings 
  according 
  to 
  

   shape: 
  (1) 
  those 
  with 
  nearly 
  circular 
  bases 
  and 
  which 
  are 
  very 
  

   symmetrical 
  and 
  almost 
  uniformly 
  steep 
  on 
  all 
  sides, 
  as 
  Potash, 
  

   Mill, 
  and 
  Stockton 
  mountains 
  and 
  the 
  top 
  of 
  Kelm 
  mountain; 
  (2) 
  

   those 
  with 
  elliptical 
  bases 
  and 
  represented 
  by 
  nearly 
  concentric 
  

   elliptical 
  contours 
  to 
  the 
  summit, 
  as 
  Moon, 
  Birch, 
  No. 
  9, 
  and 
  

   Huckleberry 
  mountains; 
  and 
  (3) 
  those 
  of 
  irregular 
  shape 
  as 
  shown 
  

   on 
  a 
  large 
  scale 
  by 
  Crane 
  mountain 
  and 
  many 
  smaller 
  masses. 
  

  

  After 
  climbing 
  all 
  the 
  domes 
  the 
  writer 
  has 
  been 
  impressed 
  by 
  

   the 
  almost 
  unrwisal 
  occurrence 
  of 
  exfoliation 
  on 
  a 
  large 
  scale 
  over 
  

   their 
  surfaces. 
  These 
  mountains 
  are 
  literally 
  peeling 
  or 
  shelling 
  

   off 
  by 
  the 
  removal 
  of 
  exfoliation 
  sheets 
  of 
  great 
  size, 
  some 
  having 
  

   been 
  noted 
  as 
  much 
  as 
  50 
  to 
  75 
  feet 
  across 
  and 
  from 
  1 
  to 
  3 
  feet 
  

   thick. 
  Among 
  many 
  other 
  good 
  places 
  to 
  observe 
  this 
  phenomenon 
  

   are 
  on 
  the 
  west 
  or 
  south 
  sides 
  of 
  Moon, 
  Crane, 
  or 
  Huckleberry 
  

   mountains. 
  Not 
  infrequently, 
  especially 
  during 
  the 
  fall 
  and 
  spring 
  

   months, 
  slabs 
  loosen 
  up 
  and 
  go 
  thundering 
  down 
  the 
  mountain 
  sides. 
  

   Though 
  the 
  rocks 
  are 
  all 
  clearly 
  gneissoid, 
  the 
  exfoliation 
  appears 
  

   entirely 
  to 
  disregard 
  this 
  structure 
  and 
  often 
  great 
  sheets 
  come 
  off 
  

   at 
  right 
  angles 
  to 
  the 
  foliation. 
  

  

  This 
  very 
  common 
  occurrence 
  of 
  exfoliation 
  domes 
  in 
  the 
  region 
  

   the 
  writer 
  believes 
  to 
  be 
  due 
  to 
  a 
  combination 
  of 
  factors 
  especially 
  

  

  