BARITE  IN  SOUTHERN  PENNSYLVANIA  AND  PURE  LIMESTONE 
IN  BERKELEY  COUNTY,  W.  VA. 
By  George  W.  Stose. 
Scattered  deposits  of  barite  occur  on  the  eastern  side  of  the  Cumber- 
land Valley  in  southern  Pennsylvania,  in  the  vicinity  of  Waynesboro. 
The  lower  Cambrian  quartzite,  forming-  the  South  Mountain  to  the 
east,  dips  beneath  the  limestone  series  of  the  valley,  which  is  here 
divisible  into  three  formations.  The  lower  2,000  db  feet  consists  of 
dark-gray  and  mottled,  massive  limestone,  in  part  siliceous,  with  purple 
shale  and  thin  sandstone,  bearing  lower  Cambrian  fossils  at  the  top; 
the  middle  2,000  ±  feet  consists  of  light-gray,  siliceous,  massive,  and 
thin-bedded,  dolomitic  limestone,  almost  barren  of  fossils,  with  cal- 
careous sandstone  and  cherty  beds  at  the  top;  and  the  upper  1,500  ± 
feet  is  composed  of  light-gray  dolomitic  limestone  with  numerous  thin, 
cherty  bands,  containing  a  fauna  of  upper  Cambrian  age,  grading  up 
into  pure  limestones,  in  part  crystalline,  becoming  carbonaceous  and 
shaly  at  the  top  and  containing  Trenton  fossils.  To  the  west  this  is 
overlain  by  the  Hudson  shale. 
The  region  is  extensively  folded.  In  general  the  mountains  strike 
northeast-southwest  and  the  valley  structures  are  parallel,  but  in  the 
vicinity  of  Waynesboro  there  are  local  pitching  folds,  which  cause  the 
mountain  to  be  offset  into  the  valley.  East  of  the  town  the  quartzite 
mountain  is  cut  off  abruptly  by  a  fault,  and  the  front  of  the  mountains 
offset  to  the  east  several  miles.  Northeast  of  the  town  there  is  a  syn- 
cline  and  a  plunging  anticline,  giving  rise  to  two  right-angle  bends  in 
the  mountain.  The  valley  rocks  follow  these  sinuosities  only  in  an 
accentuated  form.  The  sandstone  at  the  top  of  the  lower  division  of 
the  limestone  forms  a  ridge,  which  parallels  the  mountain  at  a  distance 
of  about  1J  miles.  About  5  miles  north  of  Waynesboro  there  is  another 
sharp  fold  in  the  limestone.  These  folds  have  important  relations  to 
the  deposits. 
The  barite  is  associated  with  the  limestones  and  sandy  layers  of  the 
lower  division  of  the  limestone  series,  and  is  usually  found  in  the  red- 
clay  residuum.  Such  deposits  are  discovered  in  plowing,  and  after 
the  available  material  has  been  removed  the  hole  is  filled  and  farmed 
over.     Several  tons  have  been  shipped  from  each  of  the  openings 
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