COAL  IN  NORTHWESTERN  COLORADO  AND  NORTHEASTERN  UTAH.        303 
water  level  is  composed  of  huge  white  cliff-forming  sandstone  beds 
and  some  intervening  shale,  the  whole  somewhat  conspicuous  by  con- 
trast through  the  absence  of  any  signs  of  burning.  These  beds  are 
thought  to  represent  in  part  at  least  the  lower,  relatively  barren 
sandstone  portion  of  the  Mesaverde  formation.  At  the  base,  near 
the  creek  level,  is  a  coal  bed  about  8  inches  thick,  noticeably  of  lentic- 
ular character,  and  this  is  thought  to  be  one  of  the  lower  coal  group 
described  on  page  289.  This  bed  shows  much  variation,  thickening 
and  thinning  and  dividing  in  a  manner  similar  to  that  sketched  in 
the  published  plate  of  Endlich's  report. a  It  is  doubtless  300  to  400 
feet  or  more  above  the  base  of  the  Mesaverde  formation  as  exposed 
around  the  margin  of  Raven  Park.  The  strata  above  the  huge  white 
sandstone  bed  show  a  section  of  about  300  feet  reaching  to  the  sum- 
mits of  the  adjacent  peaks  and  ridges,  composed  of  shale  and  sandy 
beds,  all  fire  reddened  or  colored  by  heat  and  baked  as  hard  as  pottery 
ware.  This  burned  rock  is  exceedingly  magnetic,  probably  owing  to 
the  reduction  of  the  iron  from  the  ferruginous  seams  contained  in  the 
strata  before  they  were  burned. 
In  a  rather  extensive  territory  adjacent  to  the  lower  valley  of 
Douglas  Creek,  or  including  nearly  all  except  the  farthest  headwaters 
of  that  stream,  the  middle  or  principal  coal  group  of  the  Mesaverde 
can  be  readily  traced  by  the  eye  from  any  prominent  point  overlook- 
ing the  district  or  by  traveling  along  the  canyon  bottoms.  The 
brilliantly  colored  rocks  may  be  seen  to  occupy  in  large  part  the  sum- 
mits of  the  ridges,  whereas  the  canyons  are  commonly  cut  into  the 
more  massive  white  beds  that  everywhere  underlie  these  coals. 
On  the  west  fork  of  the  creek,  above  the  small  anticlinal  basin 
previously  mentioned,  the  principal  coal  group  may  be  traced  approx- 
imately at  water  level  to  a  point  within  5  miles  of  White's  ranch  in 
the  upper  valley  of  the  main  stream.  The  lower  bluffs  bordering 
the  canyon  form  an  almost  continuous  rim  of  brilliant  vermilion 
rocks.  The  most  brilliant  of  these  is  a  zone  100  to  300  feet  or  more 
in  thickness.  At  the  forks  of  the  west  fork  of  Douglas  Creek,  about 
8  miles  above  the  N  Bar  ranch,  an  old  entry  exposes  a  bed  of  coal 
that  has  been  worked  for  domestic  use  at  an  old  settlement  said  to 
have  been  known  as  Smith's  ranch.  Now,  however,  both  ranch  and 
coal  entry  are  abandoned  and  fallen  into  nuns. 
The  east  fork  of  Douglas  Creek  runs  approximately  parallel  to 
the  high  escarpment  of  the  Green  River  formation  known  as  the 
Horseshoe  of  Cathedral  Bluffs.  It  also  follows  approximately  the 
upper  limit  of  the  outcrop  of  the  coal-bearing  rocks,  a  geologic 
boundary  which  trends  in  the  same  direction  as  the  high  rim  of  the 
Green  River  bluffs.  All  these  beds  have  light  dips,  and  the  formation 
above  the  principal  coal-bearing  group  carries  a  great  series  of  mass- 
« Tenth   \mi.  Rept.  U.  S.  Geol.  and  Geog.  Survey  Terr.,  1878,  PI.  V,  p.  81. 
