﻿HOLMES.] 
  JURA-TRIAS 
  AND 
  CARBONIFEROUS 
  ROCKS. 
  267 
  

  

  and 
  aspen 
  groves, 
  and 
  rich, 
  grassy 
  parks, 
  that 
  is 
  lovely 
  beyond 
  com- 
  

   parison. 
  It 
  is 
  a 
  paradise 
  within 
  a 
  day's 
  walk 
  of 
  a 
  desert, 
  and 
  its 
  beauty 
  

   is 
  much 
  enhanced 
  by 
  the 
  contrast. 
  

  

  JURA-TRTAS 
  AND 
  CARBONIFEROUS 
  ROOKS. 
  

  

  The 
  areas 
  occupied 
  by 
  Jura-Trias 
  and 
  Carboniferous 
  rocks 
  call 
  for 
  

   nothing 
  more 
  than 
  a 
  mere 
  mention, 
  as 
  they 
  are 
  quite 
  limited 
  in 
  extent, 
  

   incomplete 
  in 
  exposures, 
  and 
  totally 
  without 
  fossil 
  remains. 
  In 
  the 
  La 
  

   Plata 
  Mountains 
  there 
  are 
  exposures 
  both 
  of 
  Red 
  Beds 
  and 
  Carbonifer- 
  

   ous 
  sandstones; 
  but 
  they 
  are 
  to 
  a 
  great 
  extent 
  metamorphosed 
  beyond 
  

   recognition. 
  About 
  the'sources 
  of 
  Bear 
  River 
  there 
  are 
  also 
  exposures 
  

   of 
  the 
  rocks 
  of 
  these 
  ages, 
  but 
  I 
  was 
  not 
  enabled 
  to 
  examine 
  them. 
  In 
  

   the 
  Dolores 
  Cauon, 
  in 
  the 
  McBlmo 
  at 
  the 
  north 
  base 
  of 
  Ute 
  Peak, 
  in 
  

   the 
  Montezuma 
  Caiion, 
  and 
  on 
  the 
  Lower 
  San 
  Juan, 
  there 
  are 
  slight 
  ex- 
  

   posures 
  of 
  the 
  purple 
  laminated 
  beds 
  and 
  of 
  the 
  pink 
  and 
  red 
  sandstones. 
  

   On 
  three 
  sides 
  of 
  the 
  Carriso 
  Mountains 
  there 
  are 
  outcrops 
  of 
  the 
  Red 
  

   Beds, 
  but 
  these 
  are 
  mostly 
  beyond 
  our 
  district. 
  From 
  the 
  summits 
  of 
  the 
  

   Carriso 
  Mountains 
  I 
  obtained 
  a 
  comprehensive 
  view 
  of 
  the 
  tract 
  of 
  coun- 
  

   try 
  about 
  the 
  valleys 
  of 
  Gothic 
  Creek 
  and 
  the 
  Rio 
  de 
  Chelly 
  ; 
  nothing 
  but 
  

   red 
  and 
  white 
  sandstones 
  appear. 
  A 
  white 
  or 
  slightly 
  pinkish 
  sand- 
  

   stone 
  is 
  in 
  this 
  section 
  peculiar 
  to 
  the 
  upper 
  part 
  of 
  the 
  heavy 
  sand- 
  

   stones 
  of 
  the 
  Jura-Trias. 
  

  

  A 
  few 
  miles 
  west 
  of 
  Station 
  45, 
  on 
  the 
  San 
  Juan, 
  there 
  appears 
  to 
  

   be 
  a 
  fold 
  crossing 
  the 
  river 
  and 
  extending 
  toward 
  the 
  Abajo 
  Mountains 
  

   on 
  the 
  north, 
  and 
  far 
  into 
  Arizona 
  on 
  the 
  south. 
  A 
  very 
  noticeable 
  

   feature 
  of 
  this 
  fold 
  is 
  a 
  long 
  regular 
  line 
  of 
  white 
  and 
  pink 
  hogbacks, 
  

   which 
  can 
  be 
  seen 
  from 
  many 
  points 
  far 
  to 
  the 
  east. 
  Mr. 
  William 
  H. 
  

   Jackson, 
  on 
  his 
  way 
  to 
  the 
  Moquis 
  towns, 
  passed 
  down 
  the 
  San 
  Juan, 
  

   through 
  the 
  series 
  of 
  rocks 
  brought 
  up 
  by 
  this 
  fold, 
  and 
  his 
  descriptions, 
  

   assisted 
  by 
  a 
  number 
  of 
  characteristic 
  photographs, 
  make 
  it 
  almost 
  

   certain 
  that 
  the 
  entire 
  series 
  of 
  Jura-Trias 
  rocks 
  are 
  exposed, 
  and 
  very 
  

   probably 
  a 
  portion 
  of 
  the 
  Carboniferous. 
  At 
  the 
  mouth 
  of 
  the 
  De 
  Chelly 
  

   there 
  are 
  exposures 
  of 
  limestones 
  ; 
  beyond 
  this 
  the 
  strata 
  again 
  become 
  

   approximately 
  horizontal. 
  

  

  