302         CONTRIBUTIONS    TO    ECONOMIC   GEOLOGY,    1907,    PART   II. 
forks  of  the  creek  about  18  miles  south  of  White  River.  (See  PL 
XVIII.)  South  of  the  N  Bar  ranch,  on  the  west  fork  of  Douglas 
Creek,  a  small  topographic  basin  opens  out,  evidently  eroded  from  the 
shale  at  the  base  of  the  Mesaverde  formation,  and  this  is  therefore 
the  center  of  a  structural  dome  or  uplift,  from  which  the  beds  may 
be  observed  to  dip  outward  in  all  directions.  At  a  point  just  above 
or  south  of  this  valley  the  strata  bend  abruptly  down  (southward) 
and  there  may  also  be  a  fault  at  this  place.  For  some  distance  south 
of  this  point  the  beds  are  horizontal,  but  farther  on  they  again  rise 
approximately  at  water  grade  until  they  approach  the  headwaters  of 
this  branch  of  Douglas  Creek.  Here  the  coal-bearing  rocks,  although 
still  rising  toward  the  south,  pass  below  the  surface-water  level.  Thus 
this  group  of  beds  apparently  extends  under  the  Roan  or  Book  Cliffs 
plateau  only  10  to  15  miles  north  of  the  outcrops  of  the  same  forma- 
tion on  the  south  side  of  that  divide,  in  the  Grand  River  drainage  basin. 
In  the  western  part  of  the  Douglas  Creek  district  the  strata  lie  very 
nearly  horizontal,  with  more  or  less  irregularity  of  structure  along  the 
margin  of  the  basin  country,  this  being  evident  in  the  sinuosity  of 
the  limiting  rim  of  the  escarpments  of  the  Green  River  formation. 
The  general  light  dip  toward  the  west  or  into  the  main  Uinta  Basin 
of  Utah  is,  however,  evident  in  the  overlap  and  succession  of  higher 
and  higher  beds  in  that  direction;  so  that  the  coals  are  probably 
buried  at  greater  and  greater  depth  by  the  accumulation  of  younger 
beds. 
Faults.— A  number  of  faults  were  observed  in  the  Douglas  Creek 
district,  as  well  as  numerous  local  slides  or  slumps.  Two  miles  north 
of  the  N  Bar  ranch  a  fault  trending  N.  30°  E.  crosses  Douglas  Creek 
with  a  downthrow  of  200  feet,  more  or  less,  on  the  south  side.  This 
fault  brings  the  coal-bearing  strata  down  to  stream  grade  for  a  short 
distance,  but  beyond  they  rise  again  southward  to  the  ridge  tops — 
their  customary  situation.  Another  fault  was  observed  on  the  east 
fork  of  Douglas  Creek  about  2  miles  above  the  N  Bar  ranch.  The 
direction  of  this  fault  is  about  N.  4°  W.,  and  the  downthrow  is  200  or 
300  feet  on  the  east  side.  The  fault  plane  seems  to  be  inclined  toward 
the  west  at  a  steep  angle  on  the  north  side  of  the  gulch  and  toward 
the  east  on  the  south  side  of  the  gulch.  The  strata  are  sharply  bent, 
showing  the  drag  near  the  fault,  and  the  burned  coal-bearing  strata 
are  dropped  to  water  level  on  the  east  side.  The  abrupt  fold  above 
the  small  anticlinal  basin  on  the  west  fork  of  Douglas  Creek  is  probably 
accompanied  by  one  or  more  faults,  and  in  this  displacement  the  down- 
throw is  on  the  south  side. 
Stratigraphy  and  occurrence  of  coal. — The  stratigraphic  section  ex- 
posed at  the  main  forks  of  the  creek,  near  the  N  Bar  ranch,  is  more  or 
less  typical  of  the  Mesaverde  rocks  so  extensively  exposed  along  the 
canyon  walls  that  line  Douglas  Creek.     The  lower  400  feet  above 
