BOOK  CLIFFS  COAL  FIELD,  UTAH,  WEST  OF  GREEN  RIVER. 
By  Joseph  A.  Taff. 
LOCATION   AND   EXTENT. 
The  Book  Cliffs  coal  field  is  in  central  and  eastern  Utah.  Its  south  end  lies  in  eastern 
Sevier  County,  near  the  center  of  the  State.  From  this  locality  the  field  bears  north- 
northeast  to  Price  River  near  Castlegate,  in  western  Carbon  County.  From  Price  River 
it  curves  to  the  east  for  20  miles  and  then  bears  to  the  southeast,  crossing  Green  River 
north  of  the  Rio  Grande  Western  Railway.  Beyond  Green  River  it  turns  to  the  east  and 
northeast,  passing  into  Grand  County  and  thence  into  Colorado.  Only  that  part  of  the 
field  limited  to  Sevier,  northwestern  Emery,  and  Carbon  counties  has  been  surveyed  and 
hence  is  included  in  this  report. 
The  Book  Cliff's  coal  field  is  relatively  narrow,  comprising  the  eastern  escarpment  of  the 
Wasateli  Plateau  through  Sevier,  Emery,  and  western  Carbon  counties  and  the  southern 
face  of  the  Book  Cliff's  from  Castlegate  eastward  to  the  Colorado  line  (see  PI.  IX).  The 
lateral  extent  of  the  field  is  governed  by  the  length  and  depth  of  the  canyons  that  have 
beeti  cut  into  these  escarpments.  A  local  variation  in  width  may  be  noted  in  a  north-south 
swell  of  the  strata  situated  near  the  eastern  rim  of  the  Wasatch  Plateau  in  extreme 
western  Carbon  and  northwestern  Emery  counties.  The  mining  towns  of  Clear  Creek  and 
Winterquarters  are  on  the  northward  pitch  of  this  swell.  The  erosion  of  Pleasant  Valley 
and  the  upper  part  of  Huntington  Creek  Valley  have  exposed  the  coals  in  this  uplift.  With 
the  exception  of  Pleasant  Valley  the  canyons  cutting  the  coal-bearing  rocks  descend  from 
the  plateaus  out  through  the  faces  of  the  escarpments  into  the  rolling  plain  of  Castle  Valley. 
The  coal-bearing  strata  descend  gradually  inward  beneath  the  plateaus  from  the  middle 
slopes  of  the  front  cliffs  and  pass  beneath  the  drainage  line  of  the  canyons  and  gulches, 
as  a  rule  within  a  few  miles  of  the  front.  Exceptions  may  be  noted  in  the  case  of  Price 
River,  Huntington  Creek,  and  Gordon,  Cottonwood,  Ferron,  and  Muddy  Creek  canyons, 
where  the  coal  outcrops  extend  from  6  to  20  miles  into  the  plateaus.  In  such  instances 
the  field  of  available  coal  is  considerably  increased. 
SURFACE   FEATURES. 
The  region  of  the  Book  Cliffs  coal  field  is  an  open  country,  and  from  an  eminence  near 
the  junction  of  the  Wasatch  escarpment  and  Book  Cliffs  north  of  Price  the  observer  may 
comprehend  the  general  physical  features  of  the  whole  land  at  a  single  sweeping  view. 
The  desert  plain  of  Castle  Valley  stretches  away  to  the  limit  of  vision  toward  the  south- 
west and  southeast.  Between  the  arms  of  the  valley  toward  the  south  the  broad  rugged 
surface  of  the  San  Rafael  Swell  rises  in  the  distance.  Along  the  borders  of  Castle  Valley 
on  the  north  and  west  terraced  cliffs  rise  to  heights  of  1,500  to  2,000  feet.  These  form  the 
escarpments  of  the  Book  Cliffs  and  the  Wasatch  Plateau.  Between  Castlegate  and  Sunny- 
side  the  Book  Cliffs  Plateau  slopes  gradually  to  the  north,  in  agreement  with  the  dip  of 
the  rocks  to  the  base  of  the  Roan  Cliffs. 
Long,  tongue-like,  flat  table-lands  and  mesas  100  to  200  feet  high,  capped  by  the  thick 
sheet  of  bowlder  wash,  the  remnants  of  the  old  valley  floor,  extend  from  the  bases  of  the 
Book  Cliffs  and  Wasatch  escarpments  out  into  Castle  Valley.  At  the  borders  of  these 
table-lands  and  mesas  are  fantastically  carved  terraces  and  columns.     The  floor  of  Castle 
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