﻿GEOLOGIC 
  FORMATIONS 
  OF 
  NEW 
  YORK 
  153 
  

  

  Clinton 
  Group 
  

  

  Above 
  the 
  Medina 
  sandstone 
  lies 
  a 
  series 
  of 
  sandstones, 
  lime- 
  

   stones 
  and 
  shales, 
  which 
  receives 
  its 
  name 
  from 
  one 
  of 
  the 
  locali- 
  

   ties 
  where 
  it 
  is 
  well 
  seen, 
  the 
  vicinity 
  of 
  Clinton, 
  Oneida 
  county. 
  

   This 
  group 
  of 
  strata 
  is 
  hardly 
  distinguishable 
  east 
  of 
  Fulton 
  

   county, 
  appearing 
  to 
  thin 
  out 
  in 
  the 
  eastern 
  part 
  of 
  the 
  state, 
  

   where 
  it 
  is 
  all 
  sandstone 
  and 
  greenish 
  shale. 
  In 
  the 
  western 
  part 
  

   of 
  the 
  state, 
  however, 
  it 
  contains 
  two 
  distinct 
  layers 
  of 
  limestone 
  

   and 
  two 
  of 
  greenish 
  shale, 
  which 
  can 
  be 
  well 
  examined 
  above 
  the 
  

   lower 
  falls 
  of 
  the 
  Genesee 
  river 
  near 
  Kochester. 
  Two 
  thin 
  strata 
  

   of 
  iron 
  ore 
  are 
  found 
  in 
  this 
  group, 
  and 
  are 
  extensively 
  mined 
  in 
  

   the 
  vicinity 
  of 
  Clinton; 
  the 
  ore 
  is 
  of 
  a 
  peculiar 
  granular 
  appear- 
  

   ance 
  like 
  an 
  aggregate 
  of 
  small 
  shot, 
  and 
  contains 
  many 
  fossils 
  of 
  

   small 
  size. 
  

  

  On 
  the 
  Niagara 
  river, 
  the 
  upper 
  limestone 
  of 
  this 
  group 
  is 
  about 
  

   20 
  feet 
  thick, 
  and 
  a 
  very 
  solid, 
  massive 
  rock. 
  At 
  the 
  falls, 
  this 
  

   layer 
  is 
  near 
  the 
  level 
  of 
  the 
  water 
  below 
  the 
  cataract. 
  

  

  This 
  group 
  of 
  rocks 
  extends 
  westward 
  through 
  Canada, 
  but 
  does 
  

   not 
  appear 
  beyond 
  Wisconsin 
  as 
  a 
  distinct 
  mass. 
  It 
  re-appears 
  

   in 
  Pennsylvania 
  in 
  enormously 
  increased 
  thickness, 
  amounting 
  to 
  

   nearly 
  2,000 
  feet, 
  and 
  extends 
  southward 
  along 
  the 
  Appalachian 
  

   chain 
  even 
  to 
  eastern 
  Tennessee. 
  It 
  seems 
  everywhere 
  to 
  contain 
  

   beds 
  of 
  iron 
  ore 
  of 
  the 
  same 
  character 
  as 
  those 
  in 
  New 
  York. 
  

  

  Niagara 
  Group 
  

  

  This 
  group 
  consists 
  in 
  the 
  region 
  from 
  Wayne 
  county 
  westward 
  

   of 
  two 
  distinct 
  members, 
  a 
  shale 
  and 
  limestone, 
  which, 
  are 
  recog- 
  

   nized 
  as 
  the 
  products 
  of 
  one 
  period, 
  during 
  which, 
  there 
  was 
  an 
  

   important 
  change 
  in 
  the 
  materials 
  deposited 
  and 
  a 
  lesser 
  one 
  in 
  

   the 
  animal 
  life. 
  The 
  shale 
  is 
  a 
  very 
  uniform 
  deposit 
  throughout 
  

   the 
  whole 
  extent 
  of 
  the 
  fourth 
  district; 
  while 
  the 
  limestone, 
  from 
  

   a 
  thin, 
  dark 
  colored, 
  concretionary 
  mass 
  at 
  the 
  east 
  becomes 
  an 
  

   extensive 
  and 
  conspicuous 
  rock, 
  constantly 
  increasing 
  in 
  thick- 
  

   ness 
  in 
  a 
  westerly 
  direction, 
  even 
  far 
  beyond 
  the 
  limits 
  of 
  the 
  

   state. 
  

  

  