﻿R. 
  T. 
  Hill— 
  Ouachita 
  Mountain 
  System, 
  etc. 
  Ill 
  

  

  Art. 
  XL 
  — 
  Notes 
  on 
  a 
  Reconnaissance 
  of 
  the 
  Ouachita 
  Moun- 
  

   tain 
  System 
  in 
  Indian 
  Territory 
  ; 
  by 
  Rob't 
  T. 
  Hill.* 
  

  

  Synopsis. 
  — 
  General 
  topographic 
  features 
  of 
  Indian 
  Territory 
  including 
  Oklahoma. 
  

   The 
  northern, 
  middle 
  and 
  southern 
  belts. 
  The 
  middle 
  or 
  mountainous 
  belt. 
  

   1. 
  The 
  Eastern 
  or 
  Arkansas-Choctaw 
  Division. 
  2. 
  The 
  Central 
  or 
  Chickasaw 
  

   Division, 
  2a. 
  The 
  Wapenucka 
  Sub-division. 
  2b. 
  The 
  Tishomingo 
  Granite. 
  

   2c. 
  The 
  Arbuckle 
  Mountains 
  and 
  Washita 
  Water 
  Gap. 
  3. 
  The 
  Wichita 
  Divis- 
  

   ion. 
  Partial 
  record 
  of 
  history 
  recorded 
  in 
  the 
  Ouachita 
  System. 
  

  

  Little 
  has 
  been 
  written 
  concerning 
  the 
  geography 
  and 
  geol- 
  

   ogy 
  of 
  Indian 
  Territory, 
  and 
  the 
  writer 
  presents 
  this 
  prelim- 
  

   inary 
  paper 
  in 
  hope 
  that 
  it 
  will 
  direct 
  to 
  that 
  interesting 
  

   region 
  more 
  careful 
  and 
  detailed 
  study. 
  

  

  Topographically 
  Indian 
  Territory, 
  especially 
  its 
  southern 
  

   half, 
  presents 
  a 
  great 
  diversity 
  of 
  mountain, 
  plain, 
  forest 
  and 
  

   stream. 
  Within 
  this 
  area 
  is 
  found 
  the 
  extension 
  of 
  nearly 
  

   every 
  topographic 
  unit 
  from 
  the 
  Missouri-Kansas 
  region 
  on 
  

   the 
  north 
  to 
  the 
  Texas 
  on 
  the 
  south, 
  from 
  the 
  Great 
  Plains 
  of 
  

   the 
  west 
  to 
  the 
  forests 
  of 
  Arkansas 
  on 
  the 
  east 
  ; 
  there 
  are 
  also 
  

   many 
  unique 
  characteristic 
  features 
  of 
  the 
  region 
  itself. 
  

  

  The 
  territory 
  may 
  be 
  provisionally 
  divided 
  into 
  three 
  par- 
  

   allel 
  east 
  and 
  west 
  belts, 
  each 
  containing 
  a 
  marked 
  diversity 
  

   of 
  geologic 
  structure 
  and 
  corresponding 
  topographic 
  expression. 
  

  

  The 
  northern 
  or 
  Cherokee-Oklahoma 
  belt 
  includes 
  the 
  coun- 
  

   try 
  north 
  of 
  the 
  Canadian 
  ; 
  the 
  greater 
  part 
  is 
  prairie 
  with 
  

   spots 
  of 
  timber 
  decreasing 
  in 
  density 
  toward 
  the 
  west. 
  This 
  

   belt 
  may 
  be 
  sub-divided 
  into 
  three 
  districts 
  ; 
  the 
  eastern 
  or 
  

   Cherokee, 
  the 
  middle 
  or 
  Oklahoma, 
  the 
  western 
  or 
  Arrapahoe. 
  

   The 
  Cherokee 
  division, 
  with 
  the 
  exception 
  of 
  a 
  small 
  area 
  of 
  

   Ozark 
  hills 
  in 
  the 
  northeast 
  corner, 
  is 
  mostly 
  composed 
  of 
  Car- 
  

   boniferous 
  rocks 
  with 
  an 
  undulating 
  topography 
  similar 
  to 
  

   that 
  of 
  southeast 
  Kansas. 
  The 
  Oklahoma 
  section 
  is 
  a 
  typical 
  

   red 
  bed 
  region 
  in 
  its 
  western 
  half, 
  with 
  undulating 
  prairies 
  

   and 
  soft 
  disintegrating 
  structure. 
  The 
  Arrapahoe 
  division 
  is 
  

   the 
  ragged 
  eastern 
  border 
  of 
  the 
  great 
  plains 
  country, 
  with 
  its 
  

   characteristic 
  fresh 
  water 
  deposits 
  of 
  sands 
  and 
  grits 
  occupying 
  

   the 
  flat 
  divides, 
  as 
  originally 
  described 
  in 
  the 
  adjacent 
  west 
  

   Kansas 
  region 
  by 
  Dr. 
  J. 
  S. 
  Newberry 
  and 
  more 
  recently 
  by 
  Pro- 
  

   fessor 
  Robt. 
  Hay.f 
  These 
  plains 
  are 
  the 
  newest 
  or 
  culminating 
  

   formation 
  in 
  western 
  Texas, 
  Kansas 
  and 
  Indian 
  Territory; 
  

   they 
  are 
  now 
  slowly 
  receding 
  westward 
  because 
  of 
  the 
  head 
  

   water 
  erosion 
  of 
  the 
  streams 
  that 
  indent 
  this 
  eastern 
  border, 
  

  

  * 
  To 
  Mr. 
  James 
  S. 
  Stone, 
  of 
  Newton, 
  Massachusetts, 
  the 
  writer 
  is 
  greatly 
  in- 
  

   debted 
  for 
  his 
  faithful 
  assistance 
  in 
  conducting 
  this 
  investigation. 
  Also 
  to 
  Mr. 
  

   W. 
  L. 
  Davidson, 
  a 
  student 
  of 
  the 
  University 
  of 
  Texas. 
  

  

  f 
  See 
  Bulletin 
  57, 
  U. 
  S. 
  Geological 
  Survey. 
  

  

  Am. 
  Jour. 
  Sci. 
  — 
  Third 
  Series, 
  Vol. 
  XLII, 
  No. 
  248. 
  — 
  August, 
  1891. 
  

  

  