﻿56 
  REPORT 
  UNITED 
  STATES 
  GEOLOGICAL 
  SURVEY. 
  

  

  oo 
  

  

  Just 
  below 
  this 
  station 
  is 
  a 
  narrow 
  belt 
  of 
  gneissic 
  rocks, 
  and 
  be- 
  

   yond 
  are 
  stratified 
  beds 
  dipping 
  towards 
  the 
  southwest, 
  at 
  an 
  angle 
  of 
  

   about 
  20°, 
  while 
  those 
  on 
  the 
  station 
  have 
  a 
  very 
  gentle 
  slope 
  toward 
  

   the 
  east. 
  The 
  strata 
  that 
  are 
  tipped 
  may 
  be 
  a 
  portion 
  of 
  the 
  Lower 
  

   Triassic 
  or 
  the 
  upper 
  portion 
  of 
  the 
  Upper 
  Carboniferous. 
  I 
  incline 
  to 
  

   the 
  latter 
  view. 
  Those 
  on 
  station 
  33 
  are 
  higher 
  topographically 
  and 
  

   geologically. 
  The 
  narrow 
  belt 
  of 
  granite 
  continues 
  across 
  to 
  the 
  edge 
  

   of 
  the 
  canon, 
  and 
  we 
  can 
  follow 
  the 
  outcrop 
  of 
  red 
  beds 
  from 
  station 
  

   33 
  around 
  to 
  stations 
  39 
  and 
  34. 
  Between 
  the 
  latter 
  stations 
  a 
  creek 
  

   of 
  considerable 
  size 
  flows 
  into 
  Uuaweep 
  Caiion, 
  and 
  here 
  the 
  granitic 
  

   tongue 
  extends 
  some 
  distance 
  up 
  the 
  stream 
  on 
  tbe 
  plateau. 
  Beyond 
  

   station 
  34 
  we 
  can 
  follow 
  the 
  line^of 
  outcrop 
  of 
  red 
  beds 
  across 
  to 
  the 
  

   Gunnison 
  on 
  both 
  sides 
  of 
  the 
  canon, 
  the 
  dip 
  of 
  the 
  rocks 
  being 
  to 
  the 
  

   eastward. 
  

  

  East 
  of 
  station 
  36 
  the 
  drainage 
  is 
  toward 
  the 
  east, 
  following 
  the 
  slope 
  

   of 
  the 
  rocks, 
  in 
  which 
  the 
  creeks 
  sink 
  rapidly, 
  forming 
  canons 
  of 
  some 
  

   depth. 
  They 
  gradually 
  turn 
  to 
  the 
  northward 
  to 
  empty 
  into 
  the 
  main 
  

   stream 
  which 
  flows 
  westward, 
  finally 
  turning 
  to 
  the 
  northwest 
  to 
  flow 
  

   into 
  the 
  IJnaweep 
  Canon. 
  The 
  other 
  streams 
  between 
  stations 
  33 
  and 
  

   39 
  show 
  the 
  same 
  tendency, 
  although 
  not 
  so 
  decidedly, 
  as 
  they 
  are 
  much 
  

   shorter; 
  When 
  they 
  reach 
  the 
  edge 
  of 
  the 
  caiion 
  they 
  are 
  obliged 
  to 
  

   descend 
  precipitously 
  to 
  the 
  level 
  of 
  the 
  stream 
  at 
  its 
  bottom. 
  West 
  

   Creek, 
  in 
  CTnaweep 
  Canon, 
  rises 
  in 
  the 
  broad 
  prairie-like 
  divide 
  opposite 
  

   the 
  head 
  of 
  the 
  stream 
  flowing 
  toward 
  the 
  Gunnison. 
  The 
  average 
  fall 
  

   per 
  mile 
  is 
  only 
  4G 
  feet, 
  for 
  a 
  distance 
  of 
  8 
  miles 
  on 
  the 
  Dolores 
  side, 
  

   while 
  in 
  East 
  Creek, 
  on 
  the 
  Gunnison 
  side, 
  the 
  fall 
  is 
  105 
  feet 
  per 
  mile 
  for 
  

   about 
  the 
  same 
  distance. 
  The 
  stream 
  flowing 
  into 
  the 
  Dolores 
  is 
  the 
  

   largest 
  of 
  the 
  two. 
  Its 
  valley 
  is 
  at 
  first 
  wide 
  and 
  park-like 
  and 
  the 
  scenery 
  

   flue, 
  the 
  granite 
  wallsjising 
  like 
  buttresses 
  on 
  both 
  sides 
  of 
  the 
  valley. 
  

   As 
  we 
  go 
  down 
  the 
  canon, 
  the 
  stream 
  begins 
  to 
  descend 
  more 
  rapidly, 
  at 
  

   one 
  place 
  for 
  two 
  miles 
  descending 
  212 
  feet 
  to 
  the 
  mile 
  and 
  then 
  de- 
  

   creasing 
  again 
  to 
  an 
  average 
  of 
  94 
  feet 
  per 
  mile. 
  The 
  valley 
  is 
  very 
  

   narrow 
  where 
  the 
  creek 
  falls 
  most, 
  and 
  is 
  underlaid 
  by 
  granitoid 
  rocks, 
  

   from 
  which 
  it 
  emerges 
  into 
  conglomerates 
  of 
  Upper 
  Carboniferous 
  age, 
  

   dipping 
  to 
  the 
  westward 
  at 
  first 
  with 
  a 
  steep 
  dip, 
  gradually 
  changing 
  to 
  

   an 
  eastward 
  dip 
  of 
  5^ 
  at 
  the 
  Dolores 
  River. 
  The 
  strata 
  next 
  the 
  gran- 
  

   ite 
  are 
  conglomeritic 
  and 
  light 
  pink 
  in 
  color. 
  There 
  are 
  included 
  masses 
  

   of 
  granitic 
  rock, 
  proving 
  that 
  during 
  their 
  deposition 
  there 
  was 
  adjacent 
  

   laud 
  of 
  which 
  the 
  rocks 
  were 
  granitic. 
  Their 
  character 
  proves 
  the 
  water 
  

   to 
  have 
  been 
  shallow 
  along 
  the 
  western 
  edge 
  of 
  what 
  is 
  now 
  the 
  plateau. 
  

   On 
  the 
  Dolores 
  beds 
  of 
  lower 
  age 
  are 
  seen, 
  proving 
  that 
  there 
  was 
  

   a 
  gradual 
  subsidence. 
  This 
  is 
  also 
  proved 
  by 
  the 
  fact 
  that 
  as 
  we 
  go 
  east- 
  

   ward 
  the 
  red 
  beds 
  are 
  directly 
  superimposed 
  on 
  the 
  granitic 
  rocks, 
  and 
  

   decrease 
  m 
  thickness. 
  It 
  is 
  probable 
  that 
  there 
  is 
  a 
  line 
  of 
  faulting 
  along 
  

   the 
  plateau 
  here, 
  although 
  it 
  is 
  not 
  simple, 
  the 
  remnants 
  of 
  a 
  fold 
  being 
  

   still 
  preserved 
  in 
  the 
  upturned 
  edges 
  of 
  the 
  conglomeritic 
  sandstones. 
  

   The 
  softness 
  of 
  the 
  strata 
  has 
  caused 
  them 
  to 
  be 
  eroded, 
  and 
  where 
  the 
  

   creek 
  emerges 
  from 
  the 
  granite 
  there 
  is 
  an 
  open 
  place 
  with 
  low 
  rounded 
  

   hillocks. 
  Through 
  this 
  space 
  the 
  creek 
  flows 
  southwest. 
  Just 
  above 
  

   this 
  its 
  course 
  is 
  south, 
  with 
  a 
  western 
  turn 
  immediately 
  before 
  leaving 
  

   the 
  granite. 
  

  

  Ou 
  the 
  south 
  side 
  of 
  this 
  valley 
  bluffs 
  rise 
  nearly 
  2,000 
  feet 
  above 
  the 
  

   creek 
  level. 
  They 
  are 
  capped 
  with 
  shaly 
  beds, 
  beneath 
  which 
  is 
  a 
  mas- 
  

   sive 
  bed 
  of 
  pink 
  sandstone, 
  and 
  below 
  the 
  latter 
  is 
  an 
  equally 
  massive 
  

   bed, 
  of 
  dark 
  red 
  sandstone, 
  beneath 
  which 
  are 
  shaly 
  layers, 
  beeoming 
  

   lighter, 
  colored 
  as 
  we 
  descend. 
  Ou 
  the 
  north 
  the 
  removal 
  of 
  beds 
  has 
  

   been 
  most 
  marked. 
  

  

  