﻿t-N-DLicH.] 
  TRINIDAD 
  REGION 
  AGE 
  OF 
  COAL. 
  205 
  

  

  An 
  analysis 
  made 
  by 
  E. 
  M. 
  Kent 
  * 
  of 
  a 
  specimen 
  of 
  this 
  " 
  kidney-ore 
  " 
  

   from 
  Golden 
  City 
  showed 
  the 
  following 
  constituents 
  : 
  

  

  Per 
  cent. 
  

  

  Iron 
  41.3 
  

  

  Oxygen 
  •- 
  17. 
  7 
  

  

  Gangue 
  27.8-. 
  

  

  Water 
  12.4 
  

  

  Loss 
  0. 
  8 
  

  

  100. 
  00 
  

  

  This 
  agrees 
  very 
  well 
  with 
  the 
  decomposed 
  specimen, 
  l^o. 
  2. 
  No 
  

   doubt 
  No. 
  1 
  is 
  a 
  very 
  poor 
  one, 
  and 
  its 
  percentage 
  of 
  iron 
  wo'uld 
  be 
  but 
  

   little 
  increased 
  even 
  by 
  a 
  loss 
  of 
  certain 
  constituents 
  that 
  decomposition 
  

   would 
  eflect. 
  

  

  * 
  GEOLOGICAL 
  AGE 
  OF 
  THE 
  COAL-BEARING 
  GROUP. 
  

  

  A 
  large 
  mass 
  of 
  literature 
  has 
  accumulated, 
  with 
  a 
  view 
  to 
  arrive 
  at 
  

   a 
  final 
  determination 
  of 
  the 
  geological 
  age 
  of 
  the 
  coal-bearing 
  groups 
  

   throughout 
  the 
  Eocky 
  Mountains. 
  I 
  do 
  not 
  propose 
  to 
  prepare 
  an 
  

   elaborate 
  discussion 
  of 
  the 
  subject. 
  1 
  am 
  prevented, 
  from 
  doing 
  this, 
  

   all 
  the 
  more, 
  as 
  anything 
  I 
  could 
  state 
  with 
  reference 
  to 
  localities, 
  other 
  

   than 
  those 
  of 
  Trinidad 
  and 
  CaQon 
  City, 
  I 
  should 
  be 
  forced 
  to 
  base 
  upon 
  

   the 
  observations 
  of 
  others. 
  If 
  it 
  were 
  possible 
  that 
  a 
  survey 
  or 
  portion 
  

   of 
  a 
  survey, 
  organized 
  for 
  this 
  especial 
  purpose, 
  could 
  visit 
  all 
  the 
  local- 
  

   ities 
  involved, 
  and 
  trace 
  distinctly 
  the 
  connections 
  between 
  each 
  region 
  

   under 
  dispute, 
  it 
  would 
  require 
  but 
  a 
  comparatively 
  short 
  time 
  to 
  ar- 
  

   rive 
  at 
  a 
  final 
  conclusion; 
  one 
  that 
  would, 
  no 
  doubt, 
  be 
  acceptable 
  to 
  

   all 
  who 
  have 
  had 
  occasion 
  to 
  study 
  and 
  report 
  upon 
  the 
  "Lignitic" 
  for- 
  

   mations 
  of 
  the 
  West. 
  

  

  There 
  is 
  now 
  no 
  longer 
  room 
  for 
  any 
  doubt 
  that 
  we 
  have 
  in 
  the 
  Eocky 
  

   Mountains, 
  coalof 
  undisputable 
  Cretaceous 
  age. 
  On 
  the 
  Lower 
  Animas,t 
  

   at 
  the 
  mouth 
  of 
  the 
  Gunnison, 
  | 
  on 
  Anthracite 
  Creek, 
  § 
  and 
  a 
  number 
  of 
  

   other 
  localities, 
  coal 
  has 
  been 
  observed 
  in 
  Colorado, 
  that 
  ranges, 
  in 
  geo- 
  

   logical 
  age, 
  from 
  the 
  upper 
  members 
  of 
  the 
  Dakota 
  to 
  the 
  Fox 
  Hills 
  

   groups. 
  

  

  These 
  all 
  occupy 
  their 
  relative, 
  well 
  defined 
  horizons, 
  determined 
  by 
  

   pal 
  aeon 
  tological 
  and 
  stratigraphical 
  evidence. 
  The 
  coal 
  from 
  these 
  

   groups 
  is 
  found 
  to 
  be, 
  upon 
  analysis, 
  different 
  from 
  that 
  of 
  the 
  " 
  Lignitic"' 
  

   group. 
  More 
  especiali,y 
  is 
  this 
  difference 
  manifest 
  in 
  their 
  physical 
  

   characteristics. 
  On 
  the 
  other 
  hand, 
  we 
  find 
  coal 
  in 
  undoubted 
  Tertiary 
  

   deposits 
  which 
  are 
  equally 
  well 
  determined 
  by 
  ample 
  evidence. 
  All 
  

   that 
  coal-bearing- 
  series 
  of 
  sandstones 
  and 
  shales, 
  however, 
  in 
  the 
  region 
  

   of 
  Trinidad 
  has 
  been, 
  together 
  with 
  others, 
  a 
  bone 
  of 
  contention. 
  It 
  is 
  

   claimed 
  for 
  the 
  Cretaceous 
  and 
  for 
  the 
  Tertiary. 
  Both 
  views 
  are 
  argued 
  

   on 
  the 
  strength 
  of 
  palseontological 
  evidence, 
  besides 
  other 
  apparently 
  sat- 
  

   isfactory 
  proof. 
  *^ 
  

  

  From 
  a 
  study 
  of 
  the 
  case 
  as 
  it 
  now 
  stands, 
  I 
  cannot 
  agree 
  with 
  the 
  

   view 
  that 
  includes 
  the 
  " 
  Lignitic" 
  group 
  of 
  Trinidad 
  in 
  the 
  Cretaceous. 
  

   We 
  find, 
  at 
  the 
  base 
  of 
  the 
  Sangre 
  de 
  Cristo 
  Mountains, 
  that 
  the 
  Creta- 
  

   ceous 
  beds 
  occupy 
  a 
  position 
  iar 
  different 
  from 
  that 
  of 
  original 
  deposition. 
  

   We 
  have 
  si^en 
  that 
  the 
  coal-bearing 
  strata 
  were 
  deposited 
  in 
  a 
  basin. 
  

   They 
  com])rise 
  a 
  group 
  entirely 
  distinct 
  and 
  separate 
  from 
  the 
  adjoining 
  

  

  * 
  Rep; 
  rt 
  United 
  States 
  Geological 
  Exploration, 
  40th 
  Parallel, 
  1870, 
  vol. 
  iii, 
  p. 
  483. 
  

  

  t 
  Rcjiort 
  United 
  States 
  Geological 
  Survey, 
  1874, 
  p. 
  223. 
  

  

  t 
  Ibid., 
  p. 
  175. 
  

  

  §Ibid., 
  176, 
  and 
  Report 
  United 
  States 
  Geological 
  Survey, 
  1873, 
  p. 
  259. 
  

  

  