stonk]  OIL    AND    GAS    FIELDS    OF    GREENE    COUNTY,    PA.  407 
vious  stratum  so  long'  as  the  incline  of  the  rocks  continues  steep. 
When  it  reaches  the  crest  of  a  fold,  progress  is  stopped  and  accumu- 
lation begins.  If  oil  and  water  only  are  present,  the  oil  will  be  col- 
lected in  the  porous  rock  beneath  an  impervious  bed  along  the  crest 
of  the  fold.  If  gas,  oil,  and  water  are  present,  the}T  arrange  them- 
selves according*  to  specific  gravity,  the  gas  at  the  top  of  the  fold,  the 
oil  on  the  flanks,  and  the  water  in  the  basins  on  the  side. 
Complete  saturation  of  the  strata  with  water  aids  largely  in  the 
movement  of  oil,  but  in  the  Appalachian  field  the  deep-lying  rocks 
are  usually  dry. 
RELATION    OF   OIL    AND   GAS   POOLS    TO    STRUCTURE. 
Beginning  at  Monongahela  River  on  the  flank  of  the  Fayette  anti- 
cline, the  description  Avill  continue  westward  to  the  Former  field  on 
the  Amit}T  anticline. 
The  wells  on  the  west  bank  of  the  river  are  four  in  number.  Two 
wells  on  the  Keener-Durr  farm,  about  a  mile  below  the  mouth  of 
Whiteley  Creek,  obtained  light  flows  of  gas  in  the  Gantz  sand.  The 
Shay  well  at  the  mouth  of  the  same  creek  and  a  little  higher  on  the 
anticline  obtained  a  good  supply  in  the  Gantz. 
A  well,  started  about  150  feet  below  the  outcrop  of  the  Pittsburg 
coal  and  about  30  feet  above  the  river,  was  sunk  by  Williams  and 
Ruppert  near  the  pottery  at  Greensboro.  The  Mahoning  sandstone 
was  encountered  at  300  feet,  and  it  is  said  to  have  yielded  about  a 
barrel  of  oil  a  day.  The  Big  Injun  sand  yielded  some  gas  and  a  show 
of  oil.  The  quantity  of  oil  is  so  slight  that  the  presence  of  a  pool  can 
not  be  considered  as  established. 
Blackshire  pool. — On  Whiteley  Creek,  about  1-J-  miles  north  of 
Mapletown,  is  a  small  oil  pool.  Several  wells  were  drilled  here,  but 
only  two  were  productive,  drawing  their  supply  from  the  Big  Injun 
sand  at  depths  of  from  1,250  feet  to  1,350  feet  below  the  Pittsburg 
coal.  The  original  Blackshire  well  gave  100  barrels  a  day  at  the  start, 
but  the  production  rapidly  declined  and.  soon  ceased.  The  pool  is  situ- 
ated near  the  bottom  of  the  western  slope  of  the  Fa}^ette  anticline, 
where  the  dips  are  very  gentle.  In  the  immediate  vicinity  of  the 
wells  there  appears  to  be  a  local  flattening,  which  interrupts  the  gen- 
eral northwestward  dip  and  may  account  for  the  occurrence  of  oil  at 
this  point. 
Whiteley  Creek  field. — The  wells  in  this  field  are  confined  to  the 
immediate  vicinity  of  Whiteley  Creek  about  halfway  between  White- 
ley  and  Mapletown.  The  field  contains  a  considerable  number  of 
wells,  some  of  which  produced  100  barrels  or  more  a  day  at  the  start. 
Oil  has  been  obtained  only  from  the  upper  sands,  at  depths  of  from 
120  to  500  feet  below  the  Pittsburg  coal.     On  the  Gregg  farm,  half  a 
