﻿CHAPTER 
  V. 
  

  

  STEATIGKAPHY— 
  PALEOZOIC 
  ROCKS. 
  

  

  ABSENCE 
  OP 
  SILURIAN 
  AND 
  DEVONIAN. 
  

  

  As 
  will 
  be 
  evident 
  from 
  tlie 
  notes 
  already 
  given 
  in 
  the 
  chapters 
  on 
  

   the 
  general 
  features 
  of 
  the 
  district, 
  there 
  are 
  no 
  exposures 
  of 
  rocks 
  

   older 
  than 
  the 
  upper 
  part 
  of 
  the 
  Lower 
  Carboniferous. 
  Over 
  a 
  great 
  

   part 
  of 
  the 
  district 
  the 
  red 
  beds 
  (Triassic) 
  rest 
  immediately 
  upon 
  the 
  

   Archaean 
  . 
  rocks. 
  In 
  the 
  extreme 
  western 
  limits 
  of 
  the 
  district 
  it 
  is 
  

   probable 
  that 
  older 
  formations 
  lie 
  between. 
  Along 
  the 
  western 
  edge 
  

   of 
  the 
  Uncompahgre 
  plateau 
  we 
  have 
  Permo-Carboniferous, 
  and 
  west 
  

   of 
  the 
  Dolores 
  two 
  places 
  where 
  beds 
  of 
  Upper 
  Carboniferous 
  age 
  appear, 
  

   and 
  when 
  we 
  go 
  as 
  far 
  west 
  as 
  the 
  Grand 
  Caiion 
  of 
  the 
  Colorado 
  we 
  find 
  

   Silurian 
  strata 
  resting 
  on 
  the 
  granites. 
  Going 
  east 
  also 
  we 
  find 
  Silu- 
  

   rian 
  strata, 
  although 
  along 
  the 
  eastern 
  edge 
  of 
  the 
  Front 
  range 
  both 
  

   Silurian 
  and 
  Devonian 
  strata 
  are 
  absent 
  in 
  most 
  places. 
  During 
  early 
  

   Paleozoic 
  times 
  there 
  must, 
  therefore, 
  have 
  been 
  broad 
  areas 
  of 
  land 
  

   whose 
  rocks 
  were 
  probably 
  Archaean. 
  There 
  were 
  probably 
  numerous 
  

   small 
  islands, 
  also, 
  but 
  what 
  their 
  areas 
  and 
  limits 
  were 
  we 
  cannot 
  at 
  

   present 
  say. 
  A 
  large 
  portion 
  of 
  our 
  district 
  appears 
  to 
  have 
  been 
  above 
  

   the 
  sea-ievel 
  throughout 
  all 
  Paleozoic 
  time. 
  

  

  Devonian 
  strata 
  have 
  been 
  identified 
  in 
  various 
  portions 
  of 
  the 
  West, 
  

   and 
  doubtless 
  a 
  portion 
  of 
  the 
  limestones 
  that 
  have 
  been 
  included 
  with 
  

   the 
  Lower 
  Carboniferous 
  should 
  be 
  referred 
  to 
  a 
  lower 
  horizon. 
  I 
  had 
  

   no 
  exposures 
  of 
  Devonian 
  strata 
  in 
  my 
  district. 
  

  

  CAKBONIFEROUS. 
  

  

  The 
  existence 
  of 
  Carboniferous 
  strata 
  in 
  Colorado 
  is 
  well 
  established. 
  

   Dr. 
  Hayden 
  refers 
  to 
  the 
  Carboniferous 
  rocks 
  of 
  Camp 
  Creek, 
  near 
  Colo- 
  

   rado 
  Springs, 
  in 
  the 
  report 
  for 
  1869. 
  * 
  In 
  1873 
  1 
  found 
  fossils 
  at 
  the 
  base 
  

   of 
  the 
  Front 
  Eange, 
  near 
  Pleasant 
  Park, 
  which 
  Professor 
  Meek 
  referred 
  

   to 
  the 
  Carboniferous, 
  t 
  The 
  same 
  year 
  I 
  also 
  found 
  them 
  abundantly 
  

   in 
  the 
  Park 
  Eange, 
  | 
  and 
  they 
  have 
  been 
  gathered 
  at 
  several 
  localities 
  

   in 
  the 
  Elk 
  Mountains. 
  § 
  Mr. 
  Marvine 
  recognized 
  the 
  strata 
  north 
  of 
  

   Grand 
  Eiver 
  in 
  1874, 
  and 
  obtained 
  characteristic 
  Carboniferous 
  fossils. 
  

  

  In 
  Southern 
  Colorado, 
  Dr. 
  Endlich 
  has 
  identified 
  the 
  formation 
  and 
  

   obtained 
  typical 
  fossils. 
  

  

  In 
  our 
  district 
  of 
  1874 
  there 
  is 
  a 
  considerable 
  area, 
  in 
  which 
  Carbonif- 
  

  

  * 
  Report 
  United 
  States 
  Geological 
  Survey 
  1867, 
  1868, 
  1869, 
  p. 
  145. 
  

   t 
  Report 
  United 
  States 
  Geological 
  Survey 
  1873, 
  pp. 
  198, 
  ^31. 
  

   i 
  Report 
  United 
  States 
  Geological 
  Survey 
  1873, 
  p. 
  198. 
  

   $ 
  Reports 
  United 
  States 
  Geological 
  Survey 
  1873 
  and 
  1874. 
  

   70 
  

  

  