﻿PEALr] 
  LAKE 
  FORK 
  MOUi^TAIN 
  CREEK 
  BLUE 
  CREEK. 
  39 
  

  

  bact, 
  on 
  the 
  second 
  terrace, 
  is 
  another 
  on 
  which 
  station 
  No. 
  2 
  was 
  located. 
  

   It 
  is 
  about 
  1,000 
  feet 
  above 
  the 
  level 
  of 
  the 
  stream. 
  These 
  terraces 
  

   seem 
  to 
  mark 
  the 
  levels 
  of 
  different 
  flows 
  of 
  lava. 
  Between 
  the 
  walls 
  

   of 
  the 
  canon 
  opposite 
  Indian 
  Creek, 
  Lake 
  Fork 
  has 
  a 
  vall6y 
  half 
  a 
  

   mile 
  in 
  width, 
  which 
  gradually 
  narrows 
  as 
  we 
  go 
  up 
  the 
  creek, 
  when 
  it 
  

   begins 
  to 
  be 
  in 
  the 
  mountains, 
  or 
  when 
  we 
  go 
  down, 
  the 
  stream 
  in 
  this 
  

   direction, 
  gradually 
  cutting 
  into 
  the 
  archsean 
  rocks 
  which 
  underlie 
  the 
  

   trachytes. 
  This 
  caiion 
  is 
  a 
  true 
  box 
  caiion, 
  particularly 
  near 
  the 
  mouth 
  

   of 
  the 
  stream, 
  and 
  can 
  be 
  crossed 
  only 
  in 
  a 
  few 
  places. 
  The 
  archiiean 
  

   rocks 
  are 
  dark 
  micaceous 
  schists. 
  

  

  Station 
  No. 
  2 
  is 
  situated 
  on 
  a 
  basalt-capped 
  point, 
  which 
  marks 
  the 
  

   northern 
  edge 
  of 
  a 
  plateau 
  which 
  once 
  extended 
  farther 
  to 
  the 
  north. 
  To 
  

   the 
  southward 
  are 
  higher 
  levels. 
  Stations 
  3 
  and 
  4 
  are 
  on 
  a 
  butte-like 
  emi- 
  

   nence 
  five 
  miles 
  farther 
  west 
  and 
  five 
  miles 
  north. 
  It 
  is 
  about 
  300 
  feet 
  

   lower, 
  but 
  once, 
  probably, 
  represented 
  the 
  same 
  lithological 
  level, 
  the 
  

   rocks 
  in 
  both 
  places 
  being 
  similar 
  — 
  a 
  dark 
  vesicular 
  basalt. 
  Just 
  east 
  

   of 
  station 
  4 
  is 
  a 
  branch 
  of 
  Lake 
  Fork, 
  which 
  rises 
  in 
  the 
  hills 
  bordering 
  

   the 
  plateau 
  on 
  the 
  south. 
  On 
  the 
  west 
  is 
  Mountain 
  Creek, 
  a 
  branch 
  of 
  

   the 
  Gunnison, 
  joining 
  it 
  half 
  a 
  mile 
  below 
  the 
  mouth 
  of 
  Lake 
  Fork. 
  Be- 
  

   tween 
  these 
  streams 
  is 
  a 
  plateau 
  which, 
  as 
  I 
  have 
  already 
  said, 
  is 
  bor- 
  

   dered 
  on 
  the 
  south 
  by 
  a 
  line 
  of 
  mesa-like 
  hills, 
  well 
  wooded. 
  The 
  ends 
  

   of 
  these 
  mesas 
  are 
  between 
  the 
  branches 
  of 
  Mountain 
  Creek 
  and 
  the 
  

   west 
  fork 
  of 
  Lake 
  Fork, 
  and 
  mark 
  the 
  present 
  limit 
  of 
  a 
  volcanic 
  flow 
  

   above 
  the 
  one 
  which 
  covers 
  the 
  plateau 
  of 
  the 
  south 
  side 
  of 
  the 
  Gunni- 
  

   son. 
  North 
  of 
  stations 
  3 
  and 
  4 
  is 
  a 
  small 
  branch 
  of 
  Mountain 
  Creek 
  

   which 
  heads 
  in 
  a 
  level 
  space 
  marked 
  by 
  outcrops 
  of 
  reddish 
  gneiss. 
  

   This 
  is 
  devoid 
  of 
  soil 
  in 
  many 
  places, 
  and 
  the 
  area 
  seems 
  to 
  connect 
  the 
  

   strips 
  of 
  archasah 
  rocks 
  of 
  Lake 
  Fork 
  and 
  those 
  of 
  Mountain 
  Creek. 
  

   Where 
  the 
  trachyte 
  is 
  i^resent 
  in 
  this 
  region, 
  it 
  seems 
  to 
  rest 
  immedi- 
  

   ately 
  on 
  the 
  archtean 
  rocks, 
  showing 
  that 
  the 
  surface 
  must 
  have 
  been 
  

   very 
  irregular 
  precedent 
  to 
  the 
  lava-flows. 
  

  

  Between 
  the 
  White 
  Earth 
  and 
  Mountain 
  Creeks 
  the 
  country 
  is 
  very 
  

   open 
  and 
  grassy, 
  the 
  timber 
  being 
  confined 
  to 
  the 
  banks 
  of 
  the 
  stream, 
  

   which 
  are 
  below 
  the 
  level 
  of 
  the 
  plateau. 
  There 
  are 
  few 
  prominences— 
  

   that 
  of 
  stations 
  3 
  and 
  4 
  and 
  two 
  on 
  the 
  Gunnison 
  being 
  all 
  that 
  rise 
  

   much 
  above 
  the 
  general 
  level. 
  The 
  stream 
  next 
  west 
  of 
  Mountain 
  Creek 
  is 
  

   called 
  Blue 
  Creek 
  by 
  the 
  Indians. 
  It 
  is 
  formed 
  by 
  three 
  creeks 
  which 
  

   are 
  not 
  more 
  than 
  about 
  a 
  mile 
  apart. 
  The 
  two 
  eastern 
  streams 
  unito 
  

   on 
  the 
  south 
  side 
  of 
  a 
  high 
  mesa, 
  and 
  flow 
  at 
  right 
  angles 
  to 
  their 
  former 
  

   course 
  until 
  they 
  join 
  the 
  most 
  western 
  branch, 
  which 
  is 
  the 
  main 
  stream. 
  

   The 
  main 
  stream 
  then 
  keeps 
  on 
  in 
  its 
  original 
  direction, 
  parallel 
  to 
  the 
  orig- 
  

   inal 
  courses 
  of 
  the 
  other 
  two 
  branches. 
  (See 
  map, 
  Fig. 
  4, 
  Plate 
  I.) 
  Al- 
  

   though 
  this 
  creek 
  carries 
  considerable 
  water, 
  it 
  is 
  short, 
  when 
  compared 
  

   with 
  Lake 
  Fork. 
  The 
  main 
  stream 
  is 
  about 
  30 
  miles 
  long, 
  rising 
  in 
  the 
  Un- 
  

   compahgre 
  Mountains, 
  while 
  the 
  eastern 
  branch 
  is 
  only 
  five 
  miles 
  in 
  

   length, 
  and 
  the 
  middle 
  one, 
  which 
  is 
  formed 
  by 
  two 
  forks, 
  is 
  8 
  or 
  10 
  miles 
  

   long. 
  Altogether 
  they 
  drain 
  about 
  108 
  square 
  miles. 
  They 
  cut 
  deep 
  

   canons, 
  the 
  water 
  in 
  the 
  streams 
  being 
  from 
  500 
  to 
  600 
  feet 
  below 
  the 
  

   summitsof 
  the 
  ridges, 
  whicharecoveredwith 
  a 
  growth 
  of 
  quaking-aspens. 
  

   As 
  we 
  go 
  np-stream, 
  the 
  caiions 
  are 
  much 
  deeper, 
  which 
  is 
  the 
  case 
  

   also 
  when 
  we 
  go 
  down 
  the 
  main 
  stream. 
  The 
  wagon-road 
  of 
  Gunnison 
  

   crosses 
  the 
  ridges 
  in 
  a 
  sort 
  of 
  gap 
  that 
  separates 
  the 
  tongue-like 
  plateaus 
  

   extending 
  from 
  the 
  Uncompahgre 
  Mountains, 
  from 
  the 
  mesas 
  bordering 
  

   the 
  Gunnison 
  Eiver. 
  In 
  these 
  canons, 
  where 
  the 
  road 
  crosses, 
  the 
  rocks 
  

   are 
  gneissic, 
  and 
  upon 
  them 
  rest 
  breccias, 
  which 
  seem 
  to 
  increase 
  in 
  thick- 
  

   ness 
  toward 
  the 
  south. 
  

  

  