﻿114 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Guelph 
  dolomite 
  

  

  This 
  rock, 
  named 
  from 
  its 
  occurrence 
  at 
  Guelph 
  (Ont.) 
  about 
  75 
  

   miles 
  northwest 
  of 
  Niagara 
  falls, 
  is, 
  so 
  far 
  as 
  known, 
  absent 
  from 
  

   the 
  Niagara 
  district. 
  As 
  before 
  noted, 
  it 
  may 
  however 
  be 
  repre- 
  

   sented 
  in 
  the 
  buried 
  hundred 
  feet 
  of 
  limestone 
  (more 
  or 
  less) 
  which 
  

   he 
  above 
  the 
  130 
  feet 
  of 
  known 
  rock, 
  as 
  shown 
  by 
  the 
  borings 
  in 
  this 
  

  

  region. 
  

  

  Salina 
  beds 
  

  

  The 
  basal 
  beds 
  of 
  the 
  Upper 
  Siluric 
  are 
  the 
  saliferous 
  shales 
  and 
  

   calcareous 
  beds 
  of 
  the 
  Salina 
  stage, 
  so 
  named 
  from 
  the 
  salt-produc- 
  

   ing 
  village 
  of 
  Salina 
  in 
  Onondaga 
  county. 
  This 
  is 
  the 
  horizon 
  

   which 
  furnishes 
  all 
  the 
  salt, 
  as 
  well 
  as 
  the 
  gypsum 
  of 
  New 
  York 
  

   state 
  and 
  the 
  adjoining 
  territory. 
  In 
  the 
  Niagara 
  region 
  this 
  forma- 
  

   tion 
  is 
  not 
  well 
  exposed, 
  owing 
  to 
  the 
  soft 
  character 
  of 
  the 
  

   rock 
  which 
  has 
  permitted 
  deep 
  erosion 
  in 
  preglacial 
  times, 
  and 
  to 
  

   the 
  extensive 
  drift 
  deposits 
  which 
  cover 
  it. 
  The 
  only 
  known 
  ex- 
  

   posures 
  on 
  the 
  Niagara 
  are 
  on 
  Grand 
  island 
  and 
  on 
  the 
  Canadian 
  

   side 
  of 
  the 
  river 
  opposite 
  North 
  Buffalo. 
  On 
  Grand 
  island 
  the 
  

   Salina 
  rocks 
  may 
  be 
  seen 
  at 
  Edgewater 
  about 
  200 
  yards 
  below 
  the 
  

   boat 
  landing. 
  Here 
  the 
  following 
  section 
  is 
  exposed.^ 
  

  

  3 
  Light 
  colored, 
  soft, 
  friable 
  gypseous 
  shales, 
  5 
  feet 
  

   2 
  Greenish 
  shales 
  containing 
  nodules 
  of 
  gypsum, 
  i-J 
  feet 
  

   I 
  Black 
  shale 
  in 
  the 
  river 
  bed 
  

  

  The 
  exposure 
  extends 
  300 
  yards 
  down 
  the 
  river 
  bank. 
  

  

  At 
  the 
  extreme 
  northern 
  end 
  of 
  the 
  island, 
  where 
  it 
  divides 
  the 
  

   river, 
  an 
  impure, 
  thin 
  bedded 
  limestone 
  of 
  this 
  series 
  is 
  exposed. 
  

   The 
  exposures 
  on 
  the 
  Canadian 
  bank 
  begin 
  a 
  short 
  distance 
  south 
  

   of 
  this, 
  and 
  extend 
  to 
  the 
  International 
  bridge, 
  the 
  rock 
  here 
  being 
  

   a 
  more 
  or 
  less 
  gypsiferous 
  shale. 
  

  

  From 
  the 
  numerous 
  borings 
  in 
  this 
  region 
  we 
  have 
  however 
  

   gained 
  a 
  fair 
  knowledge 
  of 
  the 
  character 
  and 
  thickness 
  of 
  this 
  rock, 
  

   the 
  latter 
  averaging, 
  according 
  to 
  Bishop, 
  386 
  feet. 
  The 
  best 
  avail- 
  

   able 
  record 
  of 
  the 
  rocks 
  lying 
  between 
  the 
  Waterlime 
  and 
  the 
  Ni- 
  

   agara 
  series 
  of 
  limestones 
  is 
  the 
  core 
  of 
  a 
  well 
  drilled 
  on 
  the 
  land 
  

   of 
  the 
  Buffalo 
  cement 
  co. 
  in 
  North 
  Buffalo. 
  This 
  core, 
  which 
  has 
  a 
  

   'Bishop. 
  15th 
  an. 
  rep't 
  N. 
  Y. 
  state 
  geologist. 
  1895, 
  p. 
  311. 
  

  

  