﻿476 
  

  

  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Confirmatory 
  though 
  not 
  conclusive 
  evidence 
  in 
  the 
  same 
  direc- 
  

   tion 
  is 
  found 
  a 
  few 
  rods 
  north 
  of 
  the 
  locality 
  described 
  where 
  

   there 
  are 
  several 
  patches 
  of 
  impure 
  limestone 
  ranging 
  from 
  a 
  

   few 
  feet 
  up 
  to 
  some 
  rods 
  in 
  diameter, 
  which 
  are 
  also 
  with 
  much 
  

   probability 
  intrusions 
  in 
  the 
  syenite, 
  though 
  as 
  is 
  commonly 
  

   the 
  case 
  with 
  limestones 
  the 
  contacts 
  are 
  so 
  hidden 
  as 
  to 
  make 
  

   it 
  impossible 
  to 
  determine 
  the 
  relations 
  with 
  certainty. 
  

  

  Similar 
  phenomena 
  are 
  shown 
  along 
  the 
  low 
  ridge 
  extending 
  

   westward 
  from 
  near 
  the 
  railroad 
  station 
  in 
  Harrisville. 
  The 
  

   ridge 
  is 
  formed 
  by 
  the 
  syenite 
  standing 
  up 
  above 
  the 
  more 
  easily 
  

   eroded 
  limestone 
  of 
  the 
  valley, 
  and 
  the 
  two 
  formations 
  may 
  be 
  

   seen 
  along 
  the 
  line 
  of 
  contact. 
  This 
  line 
  is, 
  for 
  a 
  supposedly 
  in- 
  

   trusive 
  contact 
  surprisingly 
  straight, 
  suggesting 
  rather 
  at 
  first 
  

   sight 
  the 
  contact 
  between 
  conformable 
  formations, 
  or 
  perhaps 
  a 
  

   fault 
  line. 
  But 
  when 
  traced 
  in 
  detail 
  many 
  features 
  appear 
  that 
  

   can 
  be 
  explained 
  only 
  as 
  the 
  phenomena 
  of 
  an 
  intrusive 
  contact. 
  

  

  A 
  few 
  rods 
  south 
  of 
  the 
  station 
  the 
  syenite 
  appears 
  to 
  send 
  

   tongues 
  into 
  a 
  fine 
  grained 
  gneiss 
  of 
  the 
  limestone 
  series, 
  but 
  the 
  

   outcrops 
  are 
  poor 
  and 
  the 
  evidence 
  indecisive. 
  

  

  About 
  one 
  eighth 
  mile 
  west 
  the 
  syenite 
  forms 
  a 
  slightly 
  sinu- 
  

   ous 
  contact 
  with 
  the 
  limestone 
  and 
  with 
  a 
  peculiar 
  gneiss, 
  hav- 
  

   ing 
  the 
  appearance 
  of 
  a 
  contact 
  zone. 
  At 
  the 
  same 
  time 
  the 
  

   syenite 
  changes 
  slightly, 
  becoming 
  nearly 
  white 
  and 
  finer 
  grained. 
  

   The 
  structure 
  at 
  this 
  point 
  is 
  represented 
  diagrammatically 
  by 
  

   fig. 
  1, 
  the 
  section 
  shown 
  being 
  rather 
  less 
  than 
  a 
  rod 
  across. 
  

  

  

  wm 
  mm 
  ^m 
  

  

  Gneiss 
  Limestone 
  Syenite 
  

  

  Fig. 
  1 
  Contact 
  of 
  syenite 
  with 
  limestone 
  series. 
  Length 
  of 
  section 
  about 
  one 
  rod. 
  

  

  The 
  meaning 
  of 
  the 
  section 
  is 
  however 
  apparent 
  only 
  when 
  the 
  

   fact 
  is 
  remembered 
  that 
  the 
  structure 
  would 
  be 
  quite 
  different 
  in 
  

   other 
  sections 
  a 
  short 
  distance 
  away 
  along 
  the 
  strike. 
  The 
  sye- 
  

   nite 
  would 
  be 
  found 
  cutting 
  a 
  different 
  horizon 
  of 
  the 
  limestone 
  

   formation 
  and 
  the 
  details 
  would 
  vary 
  accordingly. 
  

  

  