THE  PUNXSUTAWNEY  AND  GLEN  CAMPBELL  COAL 
FIELDS  OF  INDIANA  AND  JEFFERSON 
COUNTIES,  PA. 
By  Frederics   I*.  Peck  and  George  II.  Ashley. 
INTRODUCTION. 
Location.^ — The  Punxsutawney  and  Glen  Campbell  coal  fields  lie  just  west  of  the  Clear- 
field County  field,  which  is  described  in  another  paper  of  fliis  bulletin  (pp.  271-275).  The 
area  discussed  is  included  in  the  Punxsutawney  quadrangle.  'Hie  I'unxsutaw  nev  field 
is  of  especial  interest,  as  it  contains  some  of  the  largest  coal  mines  in  the  United  States 
in  point  of  production  as  well  as  the  largest  continuous  hank  of  coke  ovens. 
Coals  and  associated  rocks.  The  rocks  outcropping  embrace  the  lower  half  of  the  Pens 
sylvanian  (Upper  Carboniferous)  series.  These  include  the  Allegheny  formation,  or 
Lower  Productive  Measures,  with  a  thickness  of  from  250  to  300  feet,  which  carries  the 
Freeport,  Kittanning.  and  Clarion  groups  of  coals.  These  rocks  outcrop  over  a  little  less 
than  half  of  this  quadrangle.  The  rocks  between  the  upper  Freeporl  and  Pittsburg  coals, 
of  which  about  300  feel  remain,  cover  a  little  over  one-half  of  the  area.     The  Pottsvilfl 
sandstone,  with  the  Mercer  coals,  of  little  or  no  value,  outcrops  over  limited  areas  on  little 
Mahoning  Creek  above  Richmond  and  on  Bear  Run  and  Susquehanna  River  around  McGefl 
Mills.  The  Allegheny  format  ion  contains  from  seven  to  ten  coals,  the  principal  seams  heing 
from  10 to 60 feel  apart.  Some  of  the  area  does  not  contain  any  workable  coal.  Much  or 
mosf  of  it  docs  not  show  more  than  one  good  workable  bed,  hut  sometimes  one  or  more 
thin  beds  occur  that  may  be  worked  in  t  hi'  future.  Limited  parts  of  I  he  area  contain  more 
than  one  workable  bed.  In  these  fields  the  letters  are  commonly  used  to  designate  the 
beds,  beginning  at  the  bottom.  The  correspondence  to  the  coals  of  the  Allegheny  Valley 
is  as  follows:  "A"  represents  the  Brookville,  "A' "  the  Clarion,  "B"  the  Lower  Kittanning, 
"C"  and  "C"  the  Upper  and  Middle  Kittanning,  respectively,  and  "D"  and  "E"  thl 
Lower  and  Upper  Freeport,  respectively. 
Structure. — The  Chestnut  Ridge  and  Richmond  anticlines,  which  enter  the  quadrangle 
on  both  sides  of  the  southwest  corner,  appear  to  unite  in  northeastern  Indiana  County 
and  to  continue  to  the  northeast  as  a  single  arch.  The  Punxsutawney  basin  lies  to  the 
northwest  of  this  arch  and  the  Brush  Valley  basin  to  the  southeast.  The  "B"  coal,  which 
has  an  elevation  of  2,100  feet  on  the  crest  of  the  arch  at  the  corners  of  the  three  counties, 
has  an  elevation  of  1,0.50  feet  along  the  axis  of  the  Punxsutawney  syncline  and  lies  from 
150  to  250  feet  below  drainage.  To  the  southeast  the  same  coal  descends  to  below  1 ,300  feet 
above  tide  into  the  Brush  Valley  basin.  On  the  crest  of  the  arch  the  rocks  lie  nearly  flat, 
but  on  the  flanks  they  dip  into  the  basins  at  a  rate  of  from  2  to  10  feet  in  100.  The  top 
of  the  arch  toward  the  northeast  is  fairly  broad  and  flat  and  in  that  direction  is  capped 
by  the  Mahoning  sandstone,  which  overlies  the  "E"  coal.  From  the  northeast  corner  of 
Indiana  County  tow  aid  the  soul  hwest  erosion  has  cut  down  and  removed  the  "  E"  and  "D" 
coals  over  much  of  the  crest,  those  coals  occurring  only  in  the  high  points. 
a  See  map  (fig.  11,  p.  272)  accompanying  paper  on  Clearfield  coal  field. 
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