﻿GEOLOGY 
  OF 
  THE 
  NORTH 
  CREEK 
  QUADRANGLE 
  49 
  

  

  bare 
  wall 
  of 
  syenite 
  rising 
  to 
  a 
  height 
  of 
  a 
  thousand 
  feet 
  or 
  more 
  

   on 
  the 
  south 
  side 
  of 
  Crane 
  mountain 
  is 
  a 
  truly 
  impressive 
  sight 
  

   as 
  viewed 
  from 
  the 
  valley 
  or 
  ridge 
  just 
  to 
  the 
  south. 
  As 
  viewed 
  

   from 
  the 
  summit 
  of 
  Crane 
  mountain, 
  the 
  sharp-crested 
  granite 
  

   ridge 
  forming 
  the 
  westward 
  extension 
  of 
  Little 
  mountain 
  bears 
  

   a 
  close 
  resemblance 
  to 
  a 
  typical 
  hogback 
  ridge. 
  All 
  these 
  mountain 
  

   masses 
  show 
  decided, 
  though 
  much 
  more 
  gradual, 
  downward 
  slopes 
  

   toward 
  the 
  north, 
  this 
  being 
  perfectly 
  shown 
  by 
  Crane 
  and 
  Huckle- 
  

   berry 
  mountains 
  and 
  not 
  so 
  well 
  by 
  the 
  Little 
  mountain 
  ridge. 
  

   Thus 
  the 
  general 
  areal 
  distribution 
  and 
  structural 
  relations 
  of 
  the 
  

   rocks, 
  more 
  especially 
  the 
  long, 
  regular 
  or 
  straight 
  contact 
  lines 
  

   between 
  the 
  Grenville 
  and 
  igneous 
  rocks 
  ; 
  the 
  high, 
  steep 
  walls 
  of 
  

   igneous 
  rocks 
  rising 
  above 
  the 
  Grenville 
  ; 
  and 
  the 
  distinct 
  down- 
  

   ward 
  tilt 
  of 
  the 
  mountain 
  blocks 
  northward 
  and 
  away 
  from 
  the 
  

   scarps 
  make 
  the 
  presence 
  of 
  three 
  faults 
  here 
  practically 
  certain. 
  

   The 
  picture 
  of 
  Crane 
  mountain 
  (plate 
  8) 
  clearly 
  shows 
  the 
  char- 
  

   acter 
  of 
  this 
  earth 
  block 
  with 
  its 
  steep 
  scarp 
  on 
  the 
  south 
  and 
  long 
  

   northward 
  slope. 
  

  

  For 
  reasons 
  already 
  stated, 
  nothing 
  like 
  exact 
  figures 
  can 
  be 
  

   given 
  as 
  to 
  the 
  amounts 
  of 
  displacement 
  but, 
  judging 
  by 
  the 
  pres- 
  

   ent 
  height 
  of 
  the 
  scarps, 
  the 
  throw 
  of 
  Crane 
  mountain 
  fault 
  ap- 
  

   pears 
  to 
  be 
  more 
  than 
  a 
  thousand 
  feet, 
  while 
  the 
  throw 
  of 
  the 
  

   Huckleberry 
  and 
  Little 
  mountain 
  ridge 
  faults 
  are 
  no 
  less 
  than 
  

   500 
  to 
  800 
  feet. 
  The 
  very 
  rapid 
  dying 
  out 
  of 
  these 
  faults 
  is 
  rather 
  

   remarkable, 
  but 
  perhaps 
  not 
  more 
  so 
  than 
  in 
  the 
  case 
  of 
  the 
  

   Batchellerville 
  fault 
  of 
  the 
  Broadalbin 
  quadrangle 
  recently 
  de- 
  

   scribed 
  by 
  the 
  writer. 
  

  

  As 
  shown 
  on 
  the 
  geologic 
  map, 
  a 
  minor 
  fault 
  extends 
  across 
  

   the 
  top 
  of 
  Crane 
  mountain 
  and 
  parallel 
  to 
  the 
  great 
  fault 
  just 
  south. 
  

   Three 
  high 
  points, 
  2682, 
  2829, 
  and 
  3254 
  feet 
  respectively, 
  are 
  

   arranged 
  along 
  the 
  crest 
  of 
  the 
  fault 
  scarp 
  with 
  very 
  steep 
  south 
  

   fronts 
  or 
  cliffs. 
  The 
  scarp 
  on 
  the 
  south 
  side 
  of 
  the 
  highest 
  peak 
  

   (3254 
  feet) 
  is 
  a 
  sheer 
  precipice 
  more 
  than 
  200 
  feet 
  high, 
  which 
  

   forms 
  what 
  is 
  locally 
  called 
  the 
  " 
  Nose 
  " 
  of 
  Crane 
  mountain. 
  It 
  

   is 
  well 
  shown 
  in 
  plate 
  8. 
  At 
  several 
  places 
  the 
  line 
  of 
  fracture 
  is 
  

   marked 
  by 
  distinct 
  crushed 
  or 
  sheared 
  zones 
  where 
  the 
  rock 
  is 
  

   biotitic 
  and 
  almost 
  like 
  a 
  schist 
  in 
  appearance. 
  

  

  The 
  eastern 
  face 
  of 
  Crane 
  mountain 
  rises 
  abruptly 
  along 
  a 
  

   straight 
  line 
  to 
  a 
  height 
  of 
  more 
  than 
  a 
  thousand 
  feet, 
  and 
  certainly 
  

   bears 
  every 
  resemblance 
  to 
  a 
  fault 
  scarp. 
  This 
  topographic 
  evidence, 
  

  

  *N. 
  Y. 
  State 
  Mus. 
  Bui 
  153, 
  p. 
  45- 
  

  

  