COAL  NEAR  THE  CRAZY  MOUNTAINS,  MONTANA. 
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By  R.  W.  Stone. 
INTRODUCTION. 
The  belt  of  sedimentary  rocks  extending  around  the  north  and 
west  sides  of  the  Crazy  Mountains  in  central  Montana  was  examined 
by  the  writer  in  the  summer  of  1907.  This  belt  has  been  reported05 
to  contain  several  workable  coal  beds,  and  the  main  purpose  of  the 
season's  work  was  the  investigation  of  the  coal  resources,  with  the 
idea  of  determining  as  accurately  as  possible  their  distribution, 
extent,  and  value. 
The  supposed  coal  belt  was  mapped  from  Shawmut  westward  to  the 
head  of  Musselshell  River  and  southward  to  Clyde  Fark.  A  large 
part  of  this  belt  is  included  in  the  Little  Belt  Mountains  quadrangle 
and  the  geology  is  described  in  the  folio  covering  that  area.a  A  topo- 
graphic map  covering  1,000  square  miles  was  completed  on  the  basis 
of  the  General  Land  Office  surveys.  Streams,  highways,  and  con- 
tour lines  expressing  the  relief  of  the  country  were  drawn  with  relation 
to  township  and  section  lines.  All  township  and  range  lines  were 
ridden,  and  all  the  section  lines  in  a  township  running  in  the  same 
direction,  either  north  and  south  or  east  and  west,  were  traversed  in 
the  construction  of  the  field  maps,  which  were  prepared  on  a  scale  of  2 
inches  to  the  mile,  with  a  100-foot  contour  interval. 
Much  information  regarding  the  location  of  coal  prospects  was 
obtained  from  the  ranchers.  It  was  found  on  examining  the  pros- 
pects, however,  that  there  are  no  coal  beds  of  commercially  workable 
thickness  in  the  area.  Coal  beds  are  present  and  small  amounts  of 
coal  are  taken  for  domestic  use,  but  all  the  beds  are  too  thin  for  min- 
ing on  a  commercial  scale.  The  few  ranchers  between  Shawmut  and 
Summit,  on  the  south  side  of  Musselshell  River,  who  dig  an  occa- 
a  Little  Belt  Mountains  folio  (No.  56),  Geologic  Atlas  U.  S.,  U.  S.  Geol.  Survey,  1899. 
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