﻿ECONOMIC 
  GEOLOGY 
  189 
  

  

  Oneida 
  conglomerate 
  

  

  This 
  formation 
  is 
  developed 
  to 
  its 
  greatest 
  thickness 
  in 
  the 
  

   Shawangunk 
  mountain 
  in 
  Orange 
  and 
  Ulster 
  counties. 
  

  

  It 
  is 
  recognized 
  in 
  the 
  Bellevale 
  and 
  Skunnemunk 
  mountains, 
  

   also, 
  in 
  Orange 
  county. 
  In 
  the 
  central 
  part 
  of 
  the 
  state 
  it 
  is 
  

   traced 
  westward 
  in 
  a 
  narrow 
  belt 
  from 
  Herkimer 
  county 
  into 
  

   Oneida 
  county. 
  The 
  prevailing 
  rocks 
  are 
  gray 
  and 
  reddish-gray, 
  

   silicious 
  conglomerates 
  and 
  sandstones, 
  which 
  are 
  noted 
  for 
  their 
  

   hardness 
  and 
  durability. 
  The 
  cementing 
  material 
  is 
  silicious. 
  

   The 
  jagged 
  edges 
  and 
  angular 
  blocks 
  and 
  the 
  polished 
  and 
  

   grooved 
  surfaces 
  of 
  the 
  glaciated 
  ledges, 
  so 
  common 
  on 
  the 
  

   Shawangunk 
  range, 
  afford 
  the 
  best 
  proof 
  of 
  the 
  durable 
  nature 
  

   of 
  these 
  rocks. 
  The 
  bottom 
  beds, 
  near 
  the 
  slate, 
  contain 
  some 
  

   pyrite. 
  No 
  attempt 
  has 
  been 
  made 
  to 
  open 
  quarries 
  for 
  stone, 
  

   excepting 
  at 
  a 
  few 
  localities 
  for 
  occasional 
  use 
  in 
  common 
  wall 
  

   work. 
  The 
  grit 
  rock 
  is 
  quarried 
  near 
  Esopus 
  creek 
  for 
  mill- 
  

   stones, 
  and 
  at 
  Ellenville 
  is 
  crushed 
  for 
  glass 
  sand. 
  

  

  The 
  accessibility 
  of 
  the 
  outcrops 
  to 
  the 
  New 
  York, 
  Lake 
  Erie 
  

   and 
  Western 
  railroad, 
  the 
  New 
  York, 
  Ontario 
  and 
  Western 
  rail- 
  

   road, 
  the 
  West 
  Shore 
  railroad 
  and 
  the 
  Delaware 
  and 
  Hudson 
  

   canal 
  lines 
  is 
  an 
  advantage, 
  as 
  well 
  as 
  the 
  comparative 
  nearness 
  

   to 
  New 
  York. 
  No 
  other 
  formation 
  in 
  the 
  state 
  exhibits 
  in 
  its 
  

   outcrops 
  better 
  evidence 
  of 
  ability 
  to 
  resist 
  the 
  weather. 
  

  

  Medina 
  sandstone 
  

  

  The 
  Medina 
  sandstone 
  is 
  next 
  above 
  the 
  Oneida 
  conglomerate. 
  

   It 
  is 
  recognized 
  in 
  the 
  red 
  and 
  gray 
  sandstones 
  and 
  the 
  red 
  and 
  

   mottled 
  (red 
  and 
  green) 
  shales 
  of 
  the 
  Shawangunk 
  and 
  Skunne- 
  

   munk 
  mountains 
  in 
  Orange 
  county. 
  A 
  large 
  amount 
  of 
  the 
  red 
  

   sandstone 
  has 
  been 
  quarried 
  on 
  the 
  north 
  end 
  of 
  the 
  Skunne- 
  

   munk 
  range, 
  in 
  the 
  town 
  of 
  Cornwall, 
  for 
  bridge 
  work 
  on 
  the 
  

   railroads 
  which 
  cross 
  the 
  range 
  near 
  the 
  quarry. 
  

  

  The 
  red 
  sandstone 
  is 
  seen 
  exposed 
  in 
  the 
  cuts 
  of 
  the 
  Erie 
  

   railway 
  northeast 
  of 
  Port 
  Jervis. 
  This 
  formation 
  reappears 
  in 
  

   Oswego 
  county, 
  and 
  thence 
  west 
  to 
  the 
  Niagara 
  river 
  in 
  a 
  belt 
  

   bordering 
  Lake 
  Ontario. 
  

  

  