COAL  ON   NORTHEAST  SIDE   OF  BIGHORN    BASIN,    WYO.  175 
Coal  in  the  Fort  Union  formation. — The  thickest  coal  beds  of  the 
Basin  field  are  found  in  the  Fort  Union  formation.  At  the  Rogers  & 
Gapin  coal  mine,  7  miles  south-southeast  of  Basin,  there  is  over  5  feet 
of  coal  in  one  of  these  beds,  separated  by  many  thin  partings  of  shale, 
which  are  hard  to  remove  in  mining  and  which  therefore  make  the 
commercial  product  very  dirty.  The  coal  is  too  friable  to  be  well 
adapted  to  washing.  The  following  section  was  made  at  the  working 
face  of  the  mine: 
Section  of  coal  bed  in  Rogers  &  Gapin  mine. 
Shale.  Ft.    in. 
Coal 1     7  • 
Shale H 
Coal 7£ 
Shale \ 
Coal \\ 
Shale 2 
Coal 1\ 
Shale 5 
Coal 5 
Shale 1 
Coal h\ 
Shale 1 
Coal 6i 
Bone \\ 
Coal;  said  to  be  best  part  of  bed 1    4 
Shale. 
Total  coal 5    8^ 
At  another  place  in  the  same  mine  Fisher"  made  the  following 
section  in  1905: 
Section  of  coal  bed  in  Rogers  &  Gapin  mine. 
Ft.  in. 
Coal 1     1 
Shale,  impure,  coaly 1 
Coal 8 
Shale,  black 2 
Coal 7 
Clay,  dark  gray 6 
Coal 5 
Shale,  coaly 2 
Coal 11 
Clay,  dark  gray 
Coal ' I 
Total  coal Ill 
a  Geology  and  water  resources  of  the  Bighorn  Basin:  Prof.  Paper  U.  S.  Geol.  Survey  No.  53, 1907,  p.  54. 
