﻿ENDL1CH.1 
  TRINIDAD 
  REGION 
  COAL. 
  199 
  

  

  appearance 
  of 
  tbe 
  Colorado 
  shales 
  from 
  the 
  bed 
  of 
  the 
  river. 
  Indica- 
  

   tions 
  of 
  coal 
  (/) 
  are 
  found 
  both 
  in 
  the 
  station 
  125 
  bluif 
  and 
  in 
  the 
  one 
  

   composed 
  of 
  alternating 
  sandstones 
  and 
  shales 
  {g) 
  overlying 
  it. 
  As 
  we 
  

   proceed 
  eastward 
  the 
  dip 
  of 
  the 
  strata 
  becomes 
  smaller 
  until 
  it 
  ceases 
  

   altogether, 
  and 
  we 
  soon 
  find 
  that 
  it 
  has 
  been 
  reversed, 
  that 
  it 
  is 
  now 
  west- 
  

   ward. 
  In 
  the 
  section 
  these 
  dips 
  are 
  necessarily 
  exaggerated 
  in 
  order 
  

   to 
  shorten 
  its 
  length 
  as 
  compared 
  to 
  the 
  thickness 
  of 
  the 
  strata. 
  On 
  

   the 
  Purgatorio, 
  12 
  miles 
  above 
  Trinidad, 
  we 
  find, 
  therefore, 
  the 
  out- 
  

   crop 
  of 
  a 
  heavy 
  bed 
  of 
  coal 
  {h) 
  which, 
  rising 
  farther 
  eastward, 
  seems 
  to 
  

   correspond 
  exactly 
  to 
  the 
  main 
  bank 
  (i) 
  south 
  of 
  Trinidad. 
  Ascending 
  

   from 
  that 
  point, 
  the 
  slope 
  leading 
  to 
  the 
  summit 
  of 
  Fisher's 
  Peak, 
  we 
  

   find 
  in 
  the 
  higher 
  strata 
  coal-beds 
  (Jc) 
  of 
  no 
  economic 
  importance, 
  corre- 
  

   sponding 
  to 
  the 
  small 
  ones 
  (j) 
  observed 
  farther 
  west. 
  Fisher's 
  Peak 
  

   is 
  the 
  northern 
  terminus 
  of 
  an 
  extensive 
  plateau 
  sloping 
  southward. 
  

   It 
  is 
  covered 
  by 
  600 
  to 
  650 
  feet 
  of 
  a 
  black, 
  vesicular 
  basalt 
  (/), 
  and 
  

   stands 
  out 
  prominently, 
  as 
  it 
  rises 
  to 
  an 
  absolute 
  elevation 
  of 
  9,460 
  feet, 
  

   3,300 
  feet 
  above 
  the 
  valley 
  adjoining 
  it 
  on 
  the 
  east 
  side. 
  In 
  the 
  narrow 
  

   valley 
  of 
  the 
  Purgatorio, 
  the 
  Colorado 
  shales 
  (m) 
  are 
  found, 
  containing 
  

   Inoceramus, 
  Baculites, 
  and 
  Ostrea. 
  

  

  In 
  tracing 
  connections 
  of 
  coal-beds 
  over 
  so 
  extensive 
  an 
  area 
  it 
  

   must 
  be 
  remembered 
  that 
  they 
  are 
  at 
  best 
  but 
  local 
  deposits. 
  While 
  

   the 
  conditions 
  favorable 
  to 
  the 
  formation 
  of 
  coal 
  may 
  have 
  existed 
  at 
  

   any 
  one 
  given 
  locality, 
  they 
  may 
  have 
  been 
  wantiug'at 
  the 
  same 
  time 
  

   but 
  a 
  short 
  distance 
  off. 
  Hence 
  it 
  is 
  not 
  advisable 
  to 
  attach 
  too 
  much 
  

   importance 
  to 
  over- 
  and 
  under-lying 
  beds 
  in 
  determining 
  the 
  identity 
  of 
  

   coal 
  strata. 
  Observation 
  has 
  shown 
  that 
  whereas 
  we 
  may 
  have 
  a 
  sand- 
  

   stone 
  in 
  a 
  geognostic 
  horizon 
  at 
  one 
  place, 
  that 
  same 
  sandstone 
  may 
  

   be 
  replaced 
  by 
  shales 
  or 
  marls 
  not 
  far 
  distant. 
  In 
  such 
  instances 
  the 
  

   general 
  stratigraphical 
  arrangement, 
  particularly 
  when 
  large 
  areas 
  are 
  

   involved, 
  will 
  furnish 
  by 
  far 
  the 
  better 
  data 
  upon 
  which 
  to 
  base 
  a 
  decis- 
  

   ion. 
  It 
  would 
  not 
  only 
  be 
  ill 
  advised, 
  but 
  might 
  generally 
  lead 
  to 
  erro- 
  

   neous 
  results, 
  were 
  the 
  lithological 
  constitution 
  onlv 
  of 
  certain 
  beds 
  or 
  

   strata 
  employed 
  as 
  an 
  agent 
  for 
  determination. 
  Wherever 
  fossils 
  can 
  be 
  

   found, 
  recognized 
  as 
  being 
  characteristic 
  of 
  certain 
  groups 
  or 
  members 
  of 
  

   groups, 
  their 
  evidence 
  is 
  preferable. 
  If 
  such 
  is 
  not 
  the 
  case, 
  however, 
  the 
  

   method 
  above 
  employed 
  in 
  making 
  an 
  attempt 
  at 
  deciding 
  the 
  identity 
  of 
  

   strata 
  widely 
  separated 
  will 
  usually 
  prove 
  to 
  be 
  the 
  most 
  acceptable. 
  

   It 
  will 
  furnish 
  a 
  more 
  complete 
  view 
  of 
  the 
  entire 
  stratigraphical 
  arrange- 
  

   ment, 
  and 
  though 
  due 
  consideration 
  should 
  be 
  given 
  to 
  lithological 
  evi- 
  

   dence 
  as 
  far 
  as 
  it 
  goes, 
  the 
  former 
  will 
  aid 
  more 
  materially 
  in 
  definitely 
  

   settling 
  the 
  question. 
  

  

  COAL. 
  

  

  Having 
  completed 
  the 
  discussion 
  of 
  the 
  geognostic 
  and 
  geological 
  

   position 
  occupied 
  by 
  the 
  coal 
  of 
  the 
  Trinidad 
  region 
  a 
  few 
  words 
  may 
  

   be 
  said 
  as 
  to 
  its 
  economic 
  merits. 
  On 
  the 
  Eiffenburg 
  bank 
  a 
  good 
  deal 
  

   of 
  work 
  has 
  been 
  done. 
  Nine 
  feet 
  three 
  inches 
  is 
  the 
  thickness 
  of 
  the 
  

   vein. 
  A 
  tunnel 
  has 
  been 
  driven 
  in, 
  having 
  an 
  easterly 
  direction. 
  It 
  

   was 
  at 
  the 
  time 
  of 
  my 
  visit 
  (October 
  1, 
  1875) 
  180 
  feet 
  long, 
  6 
  to 
  7 
  feet 
  

   high 
  and 
  9 
  feet 
  wide. 
  The 
  coal 
  from 
  this 
  mine 
  represents, 
  in 
  exterior 
  

   character 
  and 
  component 
  parts, 
  very 
  fairly 
  the 
  type 
  of 
  the 
  entire 
  

   region. 
  According 
  to 
  Dana's 
  classification* 
  I 
  should 
  term 
  these 
  coals 
  

   caking 
  or 
  hmding 
  hitummous 
  coal. 
  The 
  term 
  of 
  lignite 
  is 
  generally 
  used, 
  

   but 
  speaking 
  from 
  the 
  strict 
  standpoint 
  of 
  a 
  mineralogist, 
  this 
  name 
  is 
  

  

  * 
  Syst. 
  of 
  JVIin., 
  1870, 
  p. 
  654. 
  

  

  