SCHRADER    AN 
IIAWoltril. 
D]   INDEPENDENCE  QUADRANGLE,  KANSAS.  453 
way  between  Bolton  and  Caney,  two  oil  sands  occur  at  the  depths  of 
700  to  800  and  1,350  to  1,450  feet,  The  sands  that  are  struck  be- 
tween 1,350  and  1,450  feet  probably  correspond  roughly  to  those  of 
the  Tyro  pool,  where  most  of  the  oil  is  struck  at  about  1,300  feet. 
This  also  is  approximately  the  depth  at  which  the  oil  is  reached  in 
the  Bartlesville  field  in  Indian  Territory.  For  convenience  in  com- 
parison these  depths  may  be  indicated  in  the  following  table : 
Depths  <it  which  most  of  the  oil  is  found. 
'    Feet. 
Bartlesville,  Ind.  T 1,300-1,000 
Bolton 1,  100-1,  200 
Caney 1,  100-1,  200 
Cherryvale 700-    800 
Coffeeville    000 
Drum   Creek 450 
Freclonia    ___  1,100-1,150 
Independence    450-     600 
Neodesha    800-     900 
700-    800 
Sycamore.  ,   1100_1>200 
Tyro    .  1,300 
700-     800 
Wayside 
I  1,350-1,450 
Though  the  above  variations  in  depth  are  in  some  instances  due  in 
part  to  surface  relief,  intimate  association  of  dry  holes  with  produc- 
tive wells,  as  shown  by  a  study  of  the  well  logs  from  any  of  the  fields, 
indicates  that  the  oil  does  not  occur  in  a  single  continuous  stratum  of 
sand  underlying  the  field,  but  in  disconnected  lentils  at  various  hori- 
zons in  the  larger  shale  formations.  The  productive  sands  seem  to  be 
uniformly  fine  grained,  as  might  be  expected  from  close  association 
with  the  shales. 
Operation  and  development  of  the  region. — Most  of  the  wells  are 
[operated  by  companies  which  lease  the  land  for  a  stated  period  from 
the  owner,  to  whom  they  pay  a  stipulated  royalty,  which  frequently 
includes  gas  delivered  for  domestic  use  on  the  premises.  The  area 
under  one  lease  varies  from  a  few  acres  in  or  near  a  highly  produc- 
tive area  to  many  square  miles  in  a  new  or  unprospected  part  of  the 
field.     A  quarter  section  is  a  fair  average. 
There  is  a  small  independent  refinery  at  Humboldt,  which,  with 
the  others  that  are  being  built  at  Paola,  Erie,  Cherryvale,  Niotaze, 
and  elsewhere,  and  that  are  expected  to  be  in  operation  by  September, 
1905,  Avill  make  six  independent  refineries  in  all.  Since  about  1896, 
however,  operations  in  the  Kansas  field  have  been  largely  in  the  hands 
of  the  Prairie  Oil  and  Gas  Company,  the  Kansas  branch  of  the  Stand- 
ard Oil  Company,  although  during  the  latter  half  of  1898  and  the 
Ifirst  half  of  1891  many  new  companies  were  formed  and  much  devel- 
opment resulted. 
