﻿PEALE.] 
  PALEOZOIC 
  EOCKS 
  CARBONIFEROUS. 
  71 
  

  

  erous 
  rocks 
  are 
  entirely 
  wanting, 
  the 
  red 
  sandstones 
  of 
  the 
  Trias? 
  resting 
  

   immediately 
  upon 
  Archasan 
  rocks. 
  

  

  East 
  of 
  the 
  Sierra 
  la 
  Sal 
  there 
  are 
  several 
  outcrops 
  of 
  beds 
  that 
  ought 
  

   probably 
  be 
  referred 
  to 
  this 
  horizon. 
  At 
  only 
  one 
  locality 
  did 
  I 
  observe 
  

   any 
  fossils, 
  and 
  all 
  that 
  were 
  obtained 
  had 
  to 
  be 
  abandoned 
  during 
  our 
  

   difficulty 
  with 
  the 
  Indians. 
  The 
  exact 
  determination 
  of 
  the 
  age 
  of 
  the 
  

   l3eds 
  from 
  which 
  they 
  were 
  obtained 
  therefore 
  remains 
  in 
  doubt. 
  At 
  the 
  

   head 
  of 
  Salt 
  Creek 
  the 
  following 
  is 
  the 
  section 
  of 
  rocks 
  referable 
  to 
  the 
  

   Carboniferous. 
  It 
  is 
  somewhat 
  incomplete 
  from 
  the 
  fact 
  that 
  the 
  soft 
  

   character 
  of 
  the 
  beds 
  causes 
  them 
  to 
  be 
  concealed 
  by 
  debris. 
  

  

  Section 
  at 
  head 
  of 
  Salt 
  Creek. 
  

   Top. 
  Feet. 
  

  

  1. 
  Pink 
  and 
  red 
  shales 
  with 
  conglomeritic 
  sandstones, 
  becoming 
  

  

  light-colored 
  near 
  the 
  base 
  and 
  containing 
  gypsum 
  700 
  

  

  2. 
  Yellowish 
  and 
  black 
  shales 
  and 
  sandstone 
  with 
  gypsum 
  and 
  

  

  salt. 
  The 
  creek, 
  in 
  passing 
  the 
  bluff 
  where 
  these 
  beds 
  are 
  

   exposed, 
  acquires 
  a 
  strong 
  alkaline 
  taste 
  » 
  , 
  300 
  

  

  3. 
  Space 
  filled 
  with 
  shaly 
  sandstones 
  and, 
  perhaps, 
  bands 
  of 
  

  

  limestone. 
  Beds 
  for 
  most 
  part 
  entirely 
  concealed 
  .... 
  3, 
  500 
  

  

  4. 
  Light 
  yellowish 
  aud 
  greenish 
  shaly 
  sandstones 
  ) 
  ona 
  

  

  5. 
  Blue 
  limestone 
  with 
  Productus, 
  Crinoids, 
  and 
  Corals. 
  .... 
  ) 
  

  

  Total 
  4, 
  800 
  

  

  jSTo. 
  1 
  dips 
  to 
  the 
  eastward 
  at 
  an 
  angle 
  of 
  80-10°, 
  and 
  ITo. 
  2 
  in 
  the 
  

   same 
  direction 
  25°, 
  while 
  at 
  No. 
  5 
  the 
  angle 
  is 
  60°, 
  the 
  beds 
  being 
  

   tipped 
  up 
  and 
  faulted 
  against 
  the 
  ends 
  of 
  the 
  red 
  beds. 
  Taking 
  an 
  

   average 
  dip 
  of 
  30° 
  for 
  the 
  space 
  JSTo. 
  3 
  we 
  would 
  get 
  a 
  thickness 
  of 
  over 
  

   4,000 
  feet 
  of 
  beds, 
  which 
  is 
  probably 
  too 
  great. 
  I 
  have 
  estimated 
  it 
  at 
  

   3,500, 
  which 
  may 
  also 
  be 
  too 
  much. 
  The 
  steep 
  angle 
  hardly 
  extends 
  

   far 
  to 
  the 
  eastward. 
  

  

  Whether 
  the 
  layer 
  (No. 
  5) 
  containing 
  the 
  fossils 
  is 
  of 
  Subcarbonifer- 
  

   ous 
  or 
  of 
  Carboniferous 
  age 
  I 
  am 
  unable 
  to 
  determine. 
  I 
  am 
  inclined, 
  

   however, 
  to 
  place 
  it 
  near 
  the 
  line 
  separating 
  them, 
  calling 
  the 
  beds 
  in 
  

   Nos. 
  3 
  and 
  4 
  the 
  representatives 
  of 
  the 
  Coal-Measures. 
  Eastward 
  the 
  

   beds 
  rapidly 
  thin 
  out 
  and 
  Nos. 
  2, 
  3, 
  4, 
  and 
  5 
  disappear. 
  No. 
  1 
  on 
  West 
  

   Creek 
  rests 
  on 
  the 
  granite 
  and 
  is 
  made 
  up 
  of 
  coarse 
  conglomerates, 
  

   especially 
  at 
  the 
  base, 
  showing 
  the 
  near 
  proximity 
  of 
  land 
  during 
  their 
  

   formation. 
  There 
  was 
  evidently 
  a 
  shore-line 
  along 
  the 
  crest 
  of 
  the 
  

   Uncompahgre 
  plateau, 
  or 
  just 
  west 
  of 
  it, 
  and 
  the 
  pebbles 
  forming 
  the 
  

   conglomerate 
  were 
  derived 
  from 
  the 
  adjacent 
  granites. 
  Along 
  the 
  

   Dolores 
  Eiver 
  the 
  pink 
  conglomerates 
  and 
  sandstones 
  appear 
  beneath 
  

   'he 
  blood-red 
  shales 
  and 
  sandstones 
  that 
  lie 
  immediately 
  below 
  the 
  

  

  aassive 
  red 
  sandstones 
  that 
  cap 
  the 
  bluii's. 
  These 
  beds 
  will 
  be 
  referred 
  

  

  t) 
  again 
  farther 
  on. 
  

   In 
  Labyrinth 
  Canon, 
  which 
  is 
  the 
  lower 
  part 
  of 
  Canon 
  Colorado, 
  Pro- 
  

  

  f^sor 
  Newberry 
  gives 
  the 
  following 
  section 
  of 
  Carboniferous 
  rocks 
  :* 
  

  

  Feet. 
  

  

  l.Blue 
  slaty 
  argillaceous 
  limestone, 
  with 
  nodules 
  of 
  chert, 
  and 
  

   ontaining 
  crinoidal 
  columns 
  in 
  great 
  numbers, 
  Athyris 
  subtilita, 
  

   jpMeroplion, 
  Productus, 
  &c 
  20 
  

  

  2. 
  lassive 
  blue 
  limestone, 
  portions 
  of 
  which 
  are 
  quite 
  sandy, 
  

  

  gaerally 
  variable 
  in 
  color 
  and 
  composition 
  50 
  

  

  * 
  iploring 
  expedition 
  from 
  Santa 
  F6 
  to 
  junction 
  of 
  Grand 
  and 
  Green 
  Rivers. 
  Geol. 
  Re- 
  

   port, 
  i98. 
  

  

  