jjO  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,   1903.  [bull.225. 
Mam  of  the  wells  get  small  quantities  of  gas  in  the  Big  Injun, 
Gantz,  Gordon,  and  Fifth  sands.  By  far  the  largest  producer  is  the 
Bayard  sand,  which  is  found  in  this  field  at  an  average  depth  of  2,435 
feel  below  the  Pittsburg  coal.  Very  few  dry  holes  have  been  drilled 
in  this  Held. 
The  Kneisley  gas  field  is  about  2  miles  northwest  of  Spraggs  and 
surrounds  Kneisley  schoolhouse.  There  are  about  a  dozen  wells  in  this 
group,  and  most  of  them  are  producing  gas  from  the  Fifth  sand. 
These  wells  arc  located  below  the  400-foot  contour  on  the  Pittsburg 
coal,  and  the  gas  pressure  is  strong.  The  Guthrie  No.  1  showed  a 
rock  pressure  of  865  pounds.  The  Hoy  well  got  a  hole  full  of  water 
in  the  Salt  sand,  but  this  was  cased  off  and  a  big  flow  of  gas  was 
obtained  in  the  Fifth  sand.  This  field  is  on  the  flank  of  the  Bellevernon 
anticline,  seemingly  about  midway  between  the  crest  and  the  bottom 
of  the  Waynesburg  syncline. 
On  Roberts  Run,  between  Spraggs  and  Blacksville,  a  number  of  wells 
have  been  drilled.  All  seem  to  be  near  the  anticlinal  axis,  but  the  fold 
is  low,  disappearing  to  the  south.  About  half  of  the  wells  here  were 
strong  gasers  when  they  came  in,  while  the  others  were  dry  or  so 
weak  that  they  were  abandoned  as  soon  as  completed. 
Wells  in  the  Waynesburg  syncline. — -Fewer  than  20  wells  have  been 
drilled  in  that  portion  of  the  Waynesburg  syncline  which  is  shown  on 
the  accompanying  sketch  map.  Nine  of  these  holes  are  classed  as  dry; 
they  produced  nothing,  or  yielded  salt  water  and  only  a  smell  of  gas. 
Six  others  are  light  gasers  and  two  have  been  fairly  strong  wells. 
The  records  on  hand  show  that  the  Ellen  Ross  well  on  Ruff  Creek 
and  the  E.  M.  Sayers  well  at  Waynesburg  produced  a  little  oil,  but  not 
enough  to  pay  for  pumping.  In  the  Wisecarver  well,  which  is  nearest  to 
the  bottom  of  the  basin,  the  hole  was  filled  with  salt  water  to  a  depth 
of  1,200  feet  when  the  Bayard  sand  was  struck.  Two  other  wells 
struck  salt  water  in  the  Salt  and  Big  Injun  sands.  Three  of  the  gas 
wells  are  producing  from  the  Big  Injun  sand,  while  others  derive  their 
supply  from  the  Gantz,  Fifty-foot,  or  lower  sands. 
The  presence  of  gas  in  large  quantity  and  under  high  pressure  over 
so  much  of  the  western  flank  of  the  Bellevernon  anticline  near  Waynes- 
burg, and  the  almost  total  absence  of  oil  in  the  Waynesburg  syncline, 
excites  some  curosity.  The  Ross  well  yielded  about  one  barrel  of  oil 
a  day  from  the  Gantz  sand  when  first  struck,  while  the  Sayers  well 
had  only  a  show  of  oil  in  the  Fifth  sand.  The  presence  of  so  much 
gas  farther  up  the  slope  suggests  that  this  syncline  originally  con- 
tained a  considerable  quantity  of  oil,  but  that  it  has  been  entirely 
vaporized.  It  may  be  imagined  that  oil  is  preserved  as  such  where 
it  is  closely  confined  under  high  pressure,  and  that  it  changes  to  gas 
where  the  reservoir  rock  is  widely  porous  and  offers  plenty  of  space 
