﻿Report 
  of 
  the 
  State 
  Geologist. 
  559 
  

  

  which 
  are 
  covered 
  by 
  alluvium. 
  Slate 
  outcrops 
  are 
  frequent, 
  

   but 
  the 
  finest 
  exposures 
  are 
  in 
  the 
  slopes 
  of 
  the 
  Shawangunk 
  

   mountain, 
  along 
  the 
  Wallkill 
  and 
  in 
  the 
  bank 
  of 
  the 
  Hudson 
  

   river. 
  

  

  The 
  predominant 
  material 
  is 
  a 
  brown-gray 
  to 
  black, 
  mod- 
  

   erately 
  hard, 
  fissile 
  slate, 
  often 
  with 
  marked 
  cleavage 
  and 
  

   obscure 
  bedding. 
  There 
  are 
  many 
  local 
  intercalations 
  of 
  fine- 
  

   grained 
  sandstones, 
  in 
  greater 
  part 
  of 
  dark 
  color. 
  At 
  Rifton 
  

   glen 
  the 
  Wallkill 
  cuts 
  deeply 
  into 
  the 
  formation, 
  and 
  there 
  are 
  

   several 
  extensive 
  exposures 
  in 
  the 
  banks. 
  The 
  beds 
  are 
  mainly 
  

   horizontal, 
  massively-bedded, 
  fine-grained 
  sandstones, 
  with 
  thin 
  

   intercalations 
  of 
  shales. 
  They 
  are 
  considerably 
  broken 
  below 
  

   the 
  falls, 
  owing 
  to 
  local 
  faults 
  of 
  small 
  amount, 
  and 
  they 
  are 
  

   also 
  considerably 
  arched. 
  Fossils 
  occur 
  at 
  this 
  point, 
  comprising 
  

   a 
  number 
  of 
  distinctive 
  Hudson 
  river 
  species. 
  Near 
  Eddyville 
  

   the 
  slates 
  and 
  sandstones 
  are 
  extensively 
  exposed 
  in 
  the 
  banks 
  

   of 
  Eondout 
  creek, 
  overlaid 
  to 
  the 
  northward 
  by 
  the 
  Salina 
  and 
  

   lower 
  Helderberg 
  formations. 
  At 
  Eddyville 
  the 
  slates 
  are 
  

   greatly 
  contorted, 
  and 
  there 
  is 
  a 
  fine 
  exposure 
  of 
  these 
  contor- 
  

   tions 
  in 
  the 
  creek 
  banks. 
  Along 
  the 
  eastern 
  flanks 
  of 
  the 
  Sha- 
  

   wangunk 
  mountain 
  the 
  Hudson 
  river 
  beds 
  are 
  soft 
  shales, 
  and 
  

   these 
  also, 
  as 
  already 
  mentioned, 
  are 
  conspicuous 
  in 
  the 
  eroded 
  

   areas 
  within 
  the 
  mountain, 
  notably 
  north 
  of 
  Lake 
  Mohonk, 
  at 
  

   the 
  southern 
  end 
  of 
  Dickebar 
  mountain 
  ; 
  in 
  the 
  high 
  hills 
  of 
  

   Mount 
  Meenahga 
  and 
  in 
  the 
  gullies 
  on 
  the 
  west 
  slope 
  of 
  the 
  

   mountain 
  near 
  Ellenville 
  and 
  ISTapanoch. 
  In 
  the 
  vicinity 
  of 
  the 
  

   Shawangunk 
  mountain 
  the 
  slates 
  dip 
  northwest, 
  with 
  slight 
  

   unconformity 
  to 
  the 
  overlying 
  Shawangunk 
  grit, 
  as 
  already 
  

   explained, 
  but 
  to 
  the 
  eastward 
  the 
  dip 
  is 
  to 
  the 
  southeast 
  over 
  a 
  

   wide 
  area 
  extending 
  to 
  and 
  beyond 
  the 
  Walkill 
  river. 
  The 
  

   angles 
  vary 
  from 
  thirty 
  degrees 
  to 
  vertical, 
  but 
  from 
  fifty 
  

   degrees 
  to 
  seventy 
  degrees 
  are 
  most 
  frequent. 
  The 
  structure 
  of 
  

   the 
  slates 
  in 
  the 
  Walkill 
  valley 
  was 
  not 
  worked 
  out, 
  owing 
  to 
  

   the 
  lack 
  of 
  definite 
  stratigraphy 
  and 
  the 
  absence 
  of 
  continuous 
  

   outcrops 
  along 
  cross-section 
  lines. 
  Marlborough 
  mountain 
  and 
  

   its 
  northern 
  continuations 
  through 
  Lloyd 
  and 
  Esopus 
  townships 
  

   are 
  a 
  series 
  of 
  high, 
  narrow 
  parallel 
  ridges, 
  consisting 
  of 
  hard, 
  

   dark-gray, 
  flaggy 
  sandstones 
  of 
  moderately 
  coarse 
  grain. 
  The 
  

   beds 
  stand 
  nearly 
  vertical 
  and 
  their 
  structure 
  is 
  not 
  clear. 
  There 
  

  

  